Science.gov

Sample records for accident causal factors

  1. Causal Factors and Adverse Events of Aviation Accidents and Incidents Related to Integrated Vehicle Health Management

    NASA Technical Reports Server (NTRS)

    Reveley, Mary S.; Briggs, Jeffrey L.; Evans, Joni K.; Jones, Sharon M.; Kurtoglu, Tolga; Leone, Karen M.; Sandifer, Carl E.

    2011-01-01

    Causal factors in aviation accidents and incidents related to system/component failure/malfunction (SCFM) were examined for Federal Aviation Regulation Parts 121 and 135 operations to establish future requirements for the NASA Aviation Safety Program s Integrated Vehicle Health Management (IVHM) Project. Data analyzed includes National Transportation Safety Board (NSTB) accident data (1988 to 2003), Federal Aviation Administration (FAA) incident data (1988 to 2003), and Aviation Safety Reporting System (ASRS) incident data (1993 to 2008). Failure modes and effects analyses were examined to identify possible modes of SCFM. A table of potential adverse conditions was developed to help evaluate IVHM research technologies. Tables present details of specific SCFM for the incidents and accidents. Of the 370 NTSB accidents affected by SCFM, 48 percent involved the engine or fuel system, and 31 percent involved landing gear or hydraulic failure and malfunctions. A total of 35 percent of all SCFM accidents were caused by improper maintenance. Of the 7732 FAA database incidents affected by SCFM, 33 percent involved landing gear or hydraulics, and 33 percent involved the engine and fuel system. The most frequent SCFM found in ASRS were turbine engine, pressurization system, hydraulic main system, flight management system/flight management computer, and engine. Because the IVHM Project does not address maintenance issues, and landing gear and hydraulic systems accidents are usually not fatal, the focus of research should be those SCFMs that occur in the engine/fuel and flight control/structures systems as well as power systems.

  2. Causal Factors and Adverse Conditions of Aviation Accidents and Incidents Related to Integrated Resilient Aircraft Control

    NASA Technical Reports Server (NTRS)

    Reveley, Mary S.; Briggs, Jeffrey L.; Evans, Joni K.; Sandifer, Carl E.; Jones, Sharon Monica

    2010-01-01

    The causal factors of accidents from the National Transportation Safety Board (NTSB) database and incidents from the Federal Aviation Administration (FAA) database associated with loss of control (LOC) were examined for four types of operations (i.e., Federal Aviation Regulation Part 121, Part 135 Scheduled, Part 135 Nonscheduled, and Part 91) for the years 1988 to 2004. In-flight LOC is a serious aviation problem. Well over half of the LOC accidents included at least one fatality (80 percent in Part 121), and roughly half of all aviation fatalities in the studied time period occurred in conjunction with LOC. An adverse events table was updated to provide focus to the technology validation strategy of the Integrated Resilient Aircraft Control (IRAC) Project. The table contains three types of adverse conditions: failure, damage, and upset. Thirteen different adverse condition subtypes were gleaned from the Aviation Safety Reporting System (ASRS), the FAA Accident and Incident database, and the NTSB database. The severity and frequency of the damage conditions, initial test conditions, and milestones references are also provided.

  3. Assessing causality in multivariate accident models.

    PubMed

    Elvik, Rune

    2011-01-01

    This paper discusses the application of operational criteria of causality to multivariate statistical models developed to identify sources of systematic variation in accident counts, in particular the effects of variables representing safety treatments. Nine criteria of causality serving as the basis for the discussion have been developed. The criteria resemble criteria that have been widely used in epidemiology. To assess whether the coefficients estimated in a multivariate accident prediction model represent causal relationships or are non-causal statistical associations, all criteria of causality are relevant, but the most important criterion is how well a model controls for potentially confounding factors. Examples are given to show how the criteria of causality can be applied to multivariate accident prediction models in order to assess the relationships included in these models. It will often be the case that some of the relationships included in a model can reasonably be treated as causal, whereas for others such an interpretation is less supported. The criteria of causality are indicative only and cannot provide a basis for stringent logical proof of causality.

  4. A Longitudinal Analysis of the Causal Factors in Major Maritime Accidents in the USA and Canada (1996-2006)

    NASA Technical Reports Server (NTRS)

    Johnson, C. W.; Holloway, C, M.

    2007-01-01

    Accident reports provide important insights into the causes and contributory factors leading to particular adverse events. In contrast, this paper provides an analysis that extends across the findings presented over ten years investigations into maritime accidents by both the US National Transportation Safety Board (NTSB) and Canadian Transportation Safety Board (TSB). The purpose of the study was to assess the comparative frequency of a range of causal factors in the reporting of adverse events. In order to communicate our findings, we introduce J-H graphs as a means of representing the proportion of causes and contributory factors associated with human error, equipment failure and other high level classifications in longitudinal studies of accident reports. Our results suggest the proportion of causal and contributory factors attributable to direct human error may be very much smaller than has been suggested elsewhere in the human factors literature. In contrast, more attention should be paid to wider systemic issues, including the managerial and regulatory context of maritime operations.

  5. Weather Information Communications (WINCOMM) Project: Dissemination of Weather Information for the Reduction of Aviation Weather-Related Accident Causal Factors

    NASA Technical Reports Server (NTRS)

    Jarrell, Michael; Tanger, Thomas

    2004-01-01

    Weather Information Communications (WINCOMM) is part of the Weather Accident Prevention (WxAP) Project, which is part of the NASA's Aviation Safety and Security Program. The goals of WINCOMM are to facilitate the exchange of tactical and strategic weather information between air and ground. This viewgraph presentation provides information on data link decision factors, architectures, validation goals. WINCOMM is capable of providing en-route communication air-to-ground, ground-to-air, and air-to-air, even on international or intercontinental flights. The presentation also includes information on the capacity, cost, and development of data links.

  6. [Causality: risk factors and interventions].

    PubMed

    Dekkers, Olaf M; Vandenbroucke, Jan P

    2013-01-01

    A risk factor has a causal effect on a disease when the disease would not have occurred in the absence of the risk factor. Analogous reasoning applies to the effect of a particular therapy. Thinking in terms of contrasts is fundamental to causal reasoning in medicine. The contrast determines the content of the causal claim; the most important assumption here is that the prognosis between groups is comparable. Causal effects of risk factors are not always the same as the causal effect of an intervention: removal of a risk factor (e.g. smoking) for a disease does not necessarily mean that the risk will subsequently normalize. A second problem is that risk factors cannot always easily be translated into interventions. This applies to factors that cannot be changed (e.g. gender) or that can have multiple causes themselves (e.g. obesity).

  7. Causal Indicators Can Help to Interpret Factors

    ERIC Educational Resources Information Center

    Bentler, Peter M.

    2016-01-01

    The latent factor in a causal indicator model is no more than the latent factor of the factor part of the model. However, if the causal indicator variables are well-understood and help to improve the prediction of individuals' factor scores, they can help to interpret the meaning of the latent factor. Aguirre-Urreta, Rönkkö, and Marakas (2016)…

  8. Aircraft Loss of Control Causal Factors and Mitigation Challenges

    NASA Technical Reports Server (NTRS)

    Jacobson, Steven R.

    2010-01-01

    Loss of control is the leading cause of jet fatalities worldwide. Aside from their frequency of occurrence, accidents resulting from loss of aircraft control seize the public s attention by yielding a large number of fatalities in a single event. In response to the rising threat to aviation safety, the NASA Aviation Safety Program has conducted a study of the loss of control problem. This study gathered four types of information pertaining to loss of control accidents: (1) statistical data; (2) individual accident reports that cite loss of control as a contributing factor; (3) previous meta-analyses of loss of control accidents; and (4) inputs solicited from aircraft manufacturers, air carriers, researchers, and other industry stakeholders. Using these information resources, the study team identified the causal factors that were cited in the greatest number of loss of control accidents, and which were emphasized most by industry stakeholders. This report describes the study approach, the key causal factors for aircraft loss of control, and recommended mitigation strategies to make near-term impacts, mid-term impacts, and Next Generation Air Transportation System impacts on the loss of control accident statistics

  9. A Technique for Showing Causal Arguments in Accident Reports

    NASA Technical Reports Server (NTRS)

    Holloway, C. M.; Johnson, C. W.

    2005-01-01

    In the prototypical accident report, specific findings, particularly those related to causes and contributing factors, are usually written out explicitly and clearly. Also, the evidence upon which these findings are based is typically explained in detail. Often lacking, however, is any explicit discussion, description, or depiction of the arguments that connect the findings and the evidence. That is, the reports do not make clear why the investigators believe that the specific evidence they found necessarily leads to the particular findings they enumerated. This paper shows how graphical techniques can be used to depict relevant arguments supporting alternate positions on the causes of a complex road-traffic accident.

  10. Significant increase in trisomy 21 in Berlin nine months after the Chernobyl reactor accident: temporal correlation or causal relation?

    PubMed Central

    Sperling, K.; Pelz, J.; Wegner, R. D.; Dörries, A.; Grüters, A.; Mikkelsen, M.

    1994-01-01

    OBJECTIVE--To assess whether the increased prevalence of trisomy 21 in West Berlin in January 1987 might have been causally related to exposure to ionising radiation as a result of the Chernobyl reactor accident or was merely a chance event. DESIGN--Analysis of monthly prevalence of trisomy 21 in West Berlin from January 1980 to December 1989. SETTING--Confines of West Berlin. RESULTS--Owing to the former "island" situation of West Berlin and its well organised health services, ascertainment of trisomy 21 was thought to be almost complete. A cluster of 12 cases occurred in January 1987 as compared with two or three expected. After exclusion of factors that might have explained the increase, including maternal age distribution, only exposure to radiation as a result of the Chernobyl reactor accident remained. In six of seven cases that could be studied cytogenetically the extra chromosome was of maternal origin, confirming that nondisjunction had occurred at about the time of conception. CONCLUSION--On the basis of two assumptions--(a) that maternal meiosis is an error prone process susceptible to exogenous factors at the time of conception; (b) that owing to the high prevalence of iodine deficiency in Berlin a large amount of iodine-131 would have been accumulated over a short period--it is concluded that the increased prevalence of trisomy 21 in West Berlin in January 1987 was causally related to a short period of exposure to ionising radiation as a result of the Chernobyl reactor accident. PMID:8044094

  11. Human Factors in Cabin Accident Investigations

    NASA Technical Reports Server (NTRS)

    Chute, Rebecca D.; Rosekind, Mark R. (Technical Monitor)

    1996-01-01

    Human factors has become an integral part of the accident investigation protocol. However, much of the investigative process remains focussed on the flight deck, airframe, and power plant systems. As a consequence, little data has been collected regarding the human factors issues within and involving the cabin during an accident. Therefore, the possibility exists that contributing factors that lie within that domain may be overlooked. The FAA Office of Accident Investigation is sponsoring a two-day workshop on cabin safety accident investigation. This course, within the workshop, will be of two hours duration and will explore relevant areas of human factors research. Specifically, the three areas of discussion are: Information transfer and resource management, fatigue and other physical stressors, and the human/machine interface. Integration of these areas will be accomplished by providing a suggested checklist of specific cabin-related human factors questions for investigators to probe following an accident.

  12. An assessment of predominant causal factors of pilot deviations that contribute to runway incursions

    NASA Astrophysics Data System (ADS)

    Campbell, Denado M.

    The aim of this study was to identify predominant causal factors of pilot deviations in runway incursions over a two-year period. Runway incursion reports were obtained from NASA's Aviation Safety Reporting System (ASRS), and a qualitative method was used by classifying and coding each report to a specific causal factor(s). The causal factors that were used were substantiated by research from the Aircraft Owner's and Pilot's Association that found that these causal factors were the most common in runway incursion incidents and accidents. An additional causal factor was also utilized to determine the significance of pilot training in relation to runway incursions. From the reports examined, it was found that miscommunication and situational awareness have the greatest impact on pilots and are most often the major causes of runway incursions. This data can be used to assist airports, airlines, and the FAA to understand trends in pilot deviations, and to find solutions for specific problem areas in runway incursion incidents.

  13. Causality

    NASA Astrophysics Data System (ADS)

    Pearl, Judea

    2000-03-01

    Written by one of the pre-eminent researchers in the field, this book provides a comprehensive exposition of modern analysis of causation. It shows how causality has grown from a nebulous concept into a mathematical theory with significant applications in the fields of statistics, artificial intelligence, philosophy, cognitive science, and the health and social sciences. Pearl presents a unified account of the probabilistic, manipulative, counterfactual and structural approaches to causation, and devises simple mathematical tools for analyzing the relationships between causal connections, statistical associations, actions and observations. The book will open the way for including causal analysis in the standard curriculum of statistics, artifical intelligence, business, epidemiology, social science and economics. Students in these areas will find natural models, simple identification procedures, and precise mathematical definitions of causal concepts that traditional texts have tended to evade or make unduly complicated. This book will be of interest to professionals and students in a wide variety of fields. Anyone who wishes to elucidate meaningful relationships from data, predict effects of actions and policies, assess explanations of reported events, or form theories of causal understanding and causal speech will find this book stimulating and invaluable.

  14. [Epidemiological aspects and methodological difficulties in establishing the causal relationship of Chernobyl nuclear accident with cancer].

    PubMed

    Ivan, A; Azoicăi, Doina

    2002-01-01

    The epidemiological, etiologic and clinical polymorphism of the morbid states, those accounted by radioactivity included, create major obstacles in the standardization of the methods for assessing the incidence of some diseases and their lethality. The many risk factors that can associate to radiations from various sources make the epidemiological data difficult to evaluate. The Chernobyl nuclear accident has revived the concerns and research in the field of prevention, early diagnosis and intervention of the effects of nuclear radiations by development of comparative, spatial and temporal, researches based on standardized methods, thus comparable results being provided. In Romania, the multidisciplinary epidemiological researches on the effects of Chernobyl accident upon health are still limited, and consequently insignificant for global conclusions.

  15. The Analysis of the Contribution of Human Factors to the In-Flight Loss of Control Accidents

    NASA Technical Reports Server (NTRS)

    Ancel, Ersin; Shih, Ann T.

    2012-01-01

    In-flight loss of control (LOC) is currently the leading cause of fatal accidents based on various commercial aircraft accident statistics. As the Next Generation Air Transportation System (NextGen) emerges, new contributing factors leading to LOC are anticipated. The NASA Aviation Safety Program (AvSP), along with other aviation agencies and communities are actively developing safety products to mitigate the LOC risk. This paper discusses the approach used to construct a generic integrated LOC accident framework (LOCAF) model based on a detailed review of LOC accidents over the past two decades. The LOCAF model is comprised of causal factors from the domain of human factors, aircraft system component failures, and atmospheric environment. The multiple interdependent causal factors are expressed in an Object-Oriented Bayesian belief network. In addition to predicting the likelihood of LOC accident occurrence, the system-level integrated LOCAF model is able to evaluate the impact of new safety technology products developed in AvSP. This provides valuable information to decision makers in strategizing NASA's aviation safety technology portfolio. The focus of this paper is on the analysis of human causal factors in the model, including the contributions from flight crew and maintenance workers. The Human Factors Analysis and Classification System (HFACS) taxonomy was used to develop human related causal factors. The preliminary results from the baseline LOCAF model are also presented.

  16. Risk and resilience factors of persons exposed to accidents

    PubMed Central

    HERTA, DANA – CRISTINA; BRÎNDAS, PAULA; TRIFU, RALUCA; COZMAN, DOINA

    2016-01-01

    Background and aims Resilience encompasses factors promoting effective functioning in the context of adversity. Data regarding resilience in the wake of accidental trauma is still scarce. The aim of the current study is to comparatively assess adaptive, life – promoting factors in persons exposed to motor vehicle accidents (MVA) vs. persons exposed to other types of accidents, and to identify psychological factors of resilience and vulnerability in this context of trauma exposure. Methods We assessed 93 participants exposed to accidents out of 305 eligible patients from the Clinical Rehabilitation Hospital and Cluj County Emergency Hospital. The study used Reasons for Living Inventory (RFL) and Life Events Checklist. Scores were comparatively assessed for RFL items, RFL scale and subscales in participants exposed to motor vehicle accidents (MVA) vs. participants exposed to other life – threatening accidents. Results Participants exposed to MVA and those exposed to other accidents had significantly different scores in 7 RFL items. Scores were high in 4 out of 6 RFL subscales for both samples and in most items comprising these subscales, while in the other 2 subscales and in some items comprising them scores were low. Conclusions Low fear of death, physical suffering and social disapproval emerge as risk factors in persons exposed to life – threatening accidents. Love of life, courage in life and hope for the future are important resilience factors after exposure to various types of life – threatening accidents. Survival and active coping beliefs promote resilience especially after motor vehicle accidents. Coping with uncertainty are more likely to foster resilience after other types of life – threatening accidents. Attachment of the accident victim to family promotes resilience mostly after MVA, while perceived attachment of family members to the victim promotes resilience after other types of accidents. PMID:27152078

  17. The Human Factors of an Early Space Accident: Flight 3-65 of the X-15

    NASA Technical Reports Server (NTRS)

    Barshi, Immanuel; Statler, Irving C.; Orr, Jeb S.

    2015-01-01

    The X-15 was a critical research vehicle in the early days of space flight. On November 15, 1967, the X-15-3 suffered an in-flight breakup. This 191st flight of the X-15 and the 65th flight of this third configuration was the only fatal accident of the X-15 program. This paper presents an analysis, from a human factors perspective, of the events that led up to the accident. The analysis is based on the information contained in the report of the Air Force-NASA Accident Investigation Board (AIB) dated January, 1968. The AIBs analysis addressed, primarily, the events that occurred subsequent to the pilots taking direct control of the reaction control system. The analysis described here suggests that all of the events that caused the accident occurred well before the moment when the pilot switched to direct control. Consequently, the analyses and conclusions regarding the causal factors of, and the contributing factors to, the loss of Flight 3-65 presented here differ from those of the AIB based on the same evidence. Although the accident occurred in 1967, the results of the presented analysis are still relevant today. We present our analysis and discuss its implications for the safety of space operations.

  18. The Human Factors of an Early Space Accident: Flight 3-65 of the X-15

    NASA Technical Reports Server (NTRS)

    Barshi, Immanuel; Statler, Irving C.; Orr, Jeb S.

    2016-01-01

    The X-15 was a critical research vehicle in the early days of space flight. On November 15, 1967, the X-15-3 suffered an in-flight breakup. This 191st flight of the X-15 and the 65th flight of this third configuration was the only fatal accident of the X-15 program. This paper presents an analysis, from a human factors perspective, of the events that led up to the accident. The analysis is based on the information contained in the report of the Air Force-NASA Accident Investigation Board (AIB) dated January, 1968. The AIBs analysis addressed, primarily, the events that occurred subsequent to the pilot's taking direct control of the reaction control system. The analysis described here suggests that, rather than events following the pilot's switch to direct control, it was the events preceding the switch that led to the accident. Consequently, the analyses and conclusions regarding the causal factors of, and the contributing factors to, the loss of Flight 3-65 presented here differ from those of the AIB based on the same evidence. Although the accident occurred in 1967, the results of the presented analysis are still relevant today. We present our analysis and discuss its implications for the safety of space operations.

  19. Zagreb and Tenerife: Airline Accidents Involving Linguistic Factors

    ERIC Educational Resources Information Center

    Cookson, Simon

    2009-01-01

    The International Civil Aviation Organization (ICAO) is currently implementing a program to improve the language proficiency of pilots and air traffic controllers worldwide. In justifying the program, ICAO has cited a number of airline accidents that were at least partly caused by language factors. Two accidents cited by ICAO are analysed in this…

  20. Identifying Causal Risk Factors for Violence among Discharged Patients

    PubMed Central

    Coid, Jeremy W.; Kallis, Constantinos; Doyle, Mike; Shaw, Jenny; Ullrich, Simone

    2015-01-01

    Background Structured Professional Judgement (SPJ) is routinely administered in mental health and criminal justice settings but cannot identify violence risk above moderate accuracy. There is no current evidence that violence can be prevented using SPJ. This may be explained by routine application of predictive instead of causal statistical models when standardising SPJ instruments. Methods We carried out a prospective cohort study of 409 male and female patients discharged from medium secure services in England and Wales to the community. Measures were taken at baseline (pre-discharge), 6 and 12 months post-discharge using the Historical, Clinical and Risk-20 items version 3 (HCR-20v3) and Structural Assessment of Protective Factors (SAPROF). Information on violence was obtained via the McArthur community violence instrument and the Police National Computer. Results In a lagged model, HCR-20v3 and SAPROF items were poor predictors of violence. Eight items of the HCR-20v3 and 4 SAPROF items did not predict violent behaviour better than chance. In re-analyses considering temporal proximity of risk/ protective factors (exposure) on violence (outcome), risk was elevated due to violent ideation (OR 6.98, 95% CI 13.85–12.65, P<0.001), instability (OR 5.41, 95% CI 3.44–8.50, P<0.001), and poor coping/ stress (OR 8.35, 95% CI 4.21–16.57, P<0.001). All 3 risk factors were explanatory variables which drove the association with violent outcome. Self-control (OR 0.13, 95% CI 0.08–0.24, P<0.001) conveyed protective effects and explained the association of other protective factors with violence. Conclusions Using two standardised SPJ instruments, predictive (lagged) methods could not identify risk and protective factors which must be targeted in interventions for discharged patients with severe mental illness. Predictive methods should be abandoned if the aim is to progress from risk assessment to effective risk management and replaced by methods which identify factors

  1. A Causal Model of Factors Influencing Faculty Use of Technology

    ERIC Educational Resources Information Center

    Meyer, Katrina A.; Xu, Yonghong Jade

    2009-01-01

    Based on earlier studies using the 1999 and 2004 National Study of Postsecondary Faculty (NSOPF) data [1, 2], a causal model explaining faculty technology use was constructed. Path analysis was used to test the causal effects of age, gender, highest degree, discipline (health science or not), recent research productivity, and teaching load on…

  2. Human Factors in Accidents Involving Remotely Piloted Aircraft

    NASA Technical Reports Server (NTRS)

    Merlin, Peter William

    2013-01-01

    This presentation examines human factors that contribute to RPA mishaps and provides analysis of lessons learned. RPA accident data from U.S. military and government agencies were reviewed and analyzed to identify human factors issues. Common contributors to RPA mishaps fell into several major categories: cognitive factors (pilot workload), physiological factors (fatigue and stress), environmental factors (situational awareness), staffing factors (training and crew coordination), and design factors (human machine interface).

  3. FACTORS AFFECTING ROAD TRAFFIC ACCIDENTS IN BENGHAZI, LIBYA

    PubMed Central

    Al-Ghaweel, Ibrahim; Mursi, Saleh A.; Jack, Joel P.; Joel, Irene

    2009-01-01

    Objectives: The aim of the study was to evaluate the factors responsible for road traffic accidents in Benghazi. Material and Methods: Retrospective and descriptive studies were done in the years 2006-2007. The data was collected from Traffic and License Department, Benghazi. The data were analyzed, based on fatalities, the severely handicapped, hit and run victims and were correlated with age, sex, time, environmental factors, type of roads, etc. Results: One-Thousand-Two-Hundred-Sixty-Five accidents occurred between the years 2006-2007 within the Benghazi city limits; 11.14% of the injuries were fatal; 67.35% of the victims had severe injuries and 21.51% escaped with minor injuries. Table 1 shows that 73.04% lost their lives within the city limits, 13.47% on the fly-over, and 2.12% on minor roads connected to main roads within the city limits. The mean of the accidents and its standard deviation were 16.66± 25.67 with a variance of fatality of 1.54. Conclusion: It is concluded from the studies that major road traffic accidents occur because of environmental stress factors. In addition, fatalities and the seriousness of the accidents depend on a number of factors such as the age of the vehicle, safety measures, human error and time and place of accident. PMID:23012183

  4. Assessing Dynamic Spectral Causality by Lagged Adaptive Directed Transfer Function and Instantaneous Effect Factor

    PubMed Central

    Xu, Haojie; Lu, Yunfeng; Zhu, Shanan

    2014-01-01

    It is of significance to assess the dynamic spectral causality among physiological signals. Several practical estimators adapted from spectral Granger causality have been exploited to track dynamic causality based on the framework of time-varying multivariate autoregressive (tvMVAR) models. The non-zero covariance of the model’s residuals has been used to describe the instantaneous effect phenomenon in some causality estimators. However, for the situations with Gaussian residuals in some autoregressive models, it is challenging to distinguish the directed instantaneous causality if the sufficient prior information about the “causal ordering” is missing. Here, we propose a new algorithm to assess the time-varying causal ordering of tvMVAR model under the assumption that the signals follow the same acyclic causal ordering for all time lags and to estimate the instantaneous effect factor (IEF) value in order to track the dynamic directed instantaneous connectivity. The time-lagged adaptive directed transfer function (ADTF) is also estimated to assess the lagged causality after removing the instantaneous effect. In the present study, we firstly investigated the performance of the causal-ordering estimation algorithm and the accuracy of IEF value. Then, we presented the results of IEF and time-lagged ADTF method by comparing with the conventional ADTF method through simulations of various propagation models. Statistical analysis results suggest that the new algorithm could accurately estimate the causal ordering and give a good estimation of the IEF values in the Gaussian residual conditions. Meanwhile, the time-lagged ADTF approach is also more accurate in estimating the time-lagged dynamic interactions in a complex nervous system after extracting the instantaneous effect. In addition to the simulation studies, we applied the proposed method to estimate the dynamic spectral causality on real visual evoked potential (VEP) data in a human subject. Its usefulness in

  5. Human factors review for Severe Accident Sequence Analysis (SASA)

    SciTech Connect

    Krois, P.A.; Haas, P.M.; Manning, J.J.; Bovell, C.R.

    1984-01-01

    The paper will discuss work being conducted during this human factors review including: (1) support of the Severe Accident Sequence Analysis (SASA) Program based on an assessment of operator actions, and (2) development of a descriptive model of operator severe accident management. Research by SASA analysts on the Browns Ferry Unit One (BF1) anticipated transient without scram (ATWS) was supported through a concurrent assessment of operator performance to demonstrate contributions to SASA analyses from human factors data and methods. A descriptive model was developed called the Function Oriented Accident Management (FOAM) model, which serves as a structure for bridging human factors, operations, and engineering expertise and which is useful for identifying needs/deficiencies in the area of accident management. The assessment of human factors issues related to ATWS required extensive coordination with SASA analysts. The analysis was consolidated primarily to six operator actions identified in the Emergency Procedure Guidelines (EPGs) as being the most critical to the accident sequence. These actions were assessed through simulator exercises, qualitative reviews, and quantitative human reliability analyses. The FOAM descriptive model assumes as a starting point that multiple operator/system failures exceed the scope of procedures and necessitates a knowledge-based emergency response by the operators. The FOAM model provides a functionally-oriented structure for assembling human factors, operations, and engineering data and expertise into operator guidance for unconventional emergency responses to mitigate severe accident progression and avoid/minimize core degradation. Operators must also respond to potential radiological release beyond plant protective barriers. Research needs in accident management and potential uses of the FOAM model are described. 11 references, 1 figure.

  6. The five-factor model, conscientiousness, and driving accident involvement.

    PubMed

    Arthur, W; Graziano, W G

    1996-09-01

    Personality researchers and theorists are approaching consensus on the basic structure and constructs of personality. Despite the apparent consensus on the emergent five-factor model (Goldberg, 1992, 1993), less is known about external correlates of separate factors. This research examined the relations between Conscientiousness, one dimension of the model, and driving accident involvement. Using multiple measures in independent samples drawn from college students (N = 227) and a temporary employment agency (N = 250), the results generally demonstrate a significant inverse relation between Conscientiousness and driving accident involvement; individuals who rate themselves as more self-disciplined, responsible, reliable, and dependable are less likely to be involved in driving accidents than those who rate themselves lower on these attributes. The findings are consistent with other research demonstrating the relations among Conscientiousness and other tasks and job performance. Suggestions for future research are discussed. PMID:8776881

  7. Aircraft Loss-of-Control Accident Analysis

    NASA Technical Reports Server (NTRS)

    Belcastro, Christine M.; Foster, John V.

    2010-01-01

    Loss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. To gain a better understanding into aircraft loss-of-control events and possible intervention strategies, this paper presents a detailed analysis of loss-of-control accident data (predominantly from Part 121), including worst case combinations of causal and contributing factors and their sequencing. Future potential risks are also considered.

  8. Traumatic injury may be a predisposing factor for cerebrovascular accident.

    PubMed

    Wojcik, Jodi B; Benns, Matthew V; Franklin, Glen A; Harbrecht, Brian G; Broughton-Miller, Kimberly D; Frisbie, Michelle C; Smith, Jason W; Pentecost, Karina M; Bozeman, Matthew C

    2013-01-01

    The purpose of the study was to assess whether trauma may be an independent risk factor for stroke. Evidence has shown that trauma patients experience a hypercoagulable state postinjury, increasing the risk of thrombotic events. A case-controlled, retrospective analysis was performed on admitted trauma patients over a 2-year period. Results revealed that trauma patients are 1.6 times more likely to have a cerebrovascular accident (CVA) during their hospital admission, when compared with nontrauma patients with similar CVA risk factors. Several statistically significant differences between the groups were identified. On the basis of these results, trauma appears to be an independent, nonmodifiable risk factor for CVA.

  9. Seeing Perfectly Fitting Factor Models That Are Causally Misspecified: Understanding That Close-Fitting Models Can Be Worse

    ERIC Educational Resources Information Center

    Hayduk, Leslie

    2014-01-01

    Researchers using factor analysis tend to dismiss the significant ill fit of factor models by presuming that if their factor model is close-to-fitting, it is probably close to being properly causally specified. Close fit may indeed result from a model being close to properly causally specified, but close-fitting factor models can also be seriously…

  10. Age- and Sex-Specific Causal Effects of Adiposity on Cardiovascular Risk Factors

    PubMed Central

    Fall, Tove; Hägg, Sara; Ploner, Alexander; Mägi, Reedik; Fischer, Krista; Draisma, Harmen H.M.; Sarin, Antti-Pekka; Benyamin, Beben; Ladenvall, Claes; Åkerlund, Mikael; Kals, Mart; Esko, Tõnu; Nelson, Christopher P.; Kaakinen, Marika; Huikari, Ville; Mangino, Massimo; Meirhaeghe, Aline; Kristiansson, Kati; Nuotio, Marja-Liisa; Kobl, Michael; Grallert, Harald; Dehghan, Abbas; Kuningas, Maris; de Vries, Paul S.; de Bruijn, Renée F.A.G.; Willems, Sara M.; Heikkilä, Kauko; Silventoinen, Karri; Pietiläinen, Kirsi H.; Legry, Vanessa; Giedraitis, Vilmantas; Goumidi, Louisa; Syvänen, Ann-Christine; Strauch, Konstantin; Koenig, Wolfgang; Lichtner, Peter; Herder, Christian; Palotie, Aarno; Menni, Cristina; Uitterlinden, André G.; Kuulasmaa, Kari; Havulinna, Aki S.; Moreno, Luis A.; Gonzalez-Gross, Marcela; Evans, Alun; Tregouet, David-Alexandre; Yarnell, John W.G.; Virtamo, Jarmo; Ferrières, Jean; Veronesi, Giovanni; Perola, Markus; Arveiler, Dominique; Brambilla, Paolo; Lind, Lars; Kaprio, Jaakko; Hofman, Albert; Stricker, Bruno H.; van Duijn, Cornelia M.; Ikram, M. Arfan; Franco, Oscar H.; Cottel, Dominique; Dallongeville, Jean; Hall, Alistair S.; Jula, Antti; Tobin, Martin D.; Penninx, Brenda W.; Peters, Annette; Gieger, Christian; Samani, Nilesh J.; Montgomery, Grant W.; Whitfield, John B.; Martin, Nicholas G.; Groop, Leif; Spector, Tim D.; Magnusson, Patrik K.; Amouyel, Philippe; Boomsma, Dorret I.; Nilsson, Peter M.; Järvelin, Marjo-Riitta; Lyssenko, Valeriya; Metspalu, Andres; Strachan, David P.; Salomaa, Veikko; Ripatti, Samuli; Pedersen, Nancy L.; Prokopenko, Inga; McCarthy, Mark I.

    2015-01-01

    Observational studies have reported different effects of adiposity on cardiovascular risk factors across age and sex. Since cardiovascular risk factors are enriched in obese individuals, it has not been easy to dissect the effects of adiposity from those of other risk factors. We used a Mendelian randomization approach, applying a set of 32 genetic markers to estimate the causal effect of adiposity on blood pressure, glycemic indices, circulating lipid levels, and markers of inflammation and liver disease in up to 67,553 individuals. All analyses were stratified by age (cutoff 55 years of age) and sex. The genetic score was associated with BMI in both nonstratified analysis (P = 2.8 × 10−107) and stratified analyses (all P < 3.3 × 10−30). We found evidence of a causal effect of adiposity on blood pressure, fasting levels of insulin, C-reactive protein, interleukin-6, HDL cholesterol, and triglycerides in a nonstratified analysis and in the <55-year stratum. Further, we found evidence of a smaller causal effect on total cholesterol (P for difference = 0.015) in the ≥55-year stratum than in the <55-year stratum, a finding that could be explained by biology, survival bias, or differential medication. In conclusion, this study extends previous knowledge of the effects of adiposity by providing sex- and age-specific causal estimates on cardiovascular risk factors. PMID:25712996

  11. Causal Factors Influencing Adversity Quotient of Twelfth Grade and Third-Year Vocational Students

    ERIC Educational Resources Information Center

    Pangma, Rachapoom; Tayraukham, Sombat; Nuangchalerm, Prasart

    2009-01-01

    Problem statement: The aim of this research was to study the causal factors influencing students' adversity between twelfth grade and third-year vocational students in Sisaket province, Thailand. Six hundred and seventy two of twelfth grade and 376 third-year vocational students were selected by multi-stage random sampling techniques. Approach:…

  12. The impact of environmental factors on traffic accidents in Iran

    PubMed Central

    Lankarani, Kamran B.; Heydari, Seyed Taghi; Aghabeigi, Mohammad Reza; Moafian, Ghasem; Hoseinzadeh, Amin; Vossoughi, Mehrdad

    2014-01-01

    Abstract: Background: Road traffic crashes are the third highest cause of mortality in Iran. The aim of this study was to determine the impact of roadway environmental factors on traffic crash. Methods: This cross-sectional study was conducted in Iran between March 21, 2010 and December 30, 2010. The data on road traffic crashes were obtained from the Traffic Police Department records. These records were classified to control for the main confounders related to the type of crash and roadway environmental factors. Roadway environmental factors included crash scene light, weather, place of accident, the defects and geometrics of roadway and road surface. Results: The study included 542,863 traffic crashes. The proportions of road traffic crash which led to injury were 24.44% at sunrise and 27.16% at sunset compared with 5.43% and 1.43% deaths at sunrise and sunset respectively. In regard to day time accidents, the proportions were 20.50% injuries and 0.55% deaths. The statistical analysis of the results showed that the ratio of injuries and deaths were significantly higher at sunrise and sunset than those occurring during daytime (P less than 0.001). The highest rate of death (5.07%) was due to dusty weather compared to 5.07% for other weather conditions (P less than 0.001). The highest mortality rate (3.45%) occurred on oily surfaces (P less than 0.001). The defective traffic signs were responsible for 30,046 injuries and 5.58% deaths, and road narrowing accounted for 22,775 injuries and, 4.23% deaths which indicated that the roadway defects inflict most frequent injuries and deaths. The lowest (0.74 %) and highest (3.09%) proportion of traffic crash- related deaths were due to flat straight and winding uphill/downhill roads respectively (P less than 0.001). Conclusions: Sunrise, sunset, dusty weather, oily road surfaces and winding uphill/downhill road were hazardous environmental factors. This study provides an insight into the potential impacts of environmental

  13. The influence of linguistic and cognitive factors on the time course of verb-based implicit causality.

    PubMed

    Koornneef, Arnout; Dotlačil, Jakub; van den Broek, Paul; Sanders, Ted

    2016-01-01

    In three eye-tracking experiments the influence of the Dutch causal connective "want" (because) and the working memory capacity of readers on the usage of verb-based implicit causality was examined. Experiments 1 and 2 showed that although a causal connective is not required to activate implicit causality information during reading, effects of implicit causality surfaced more rapidly and were more pronounced when a connective was present in the discourse than when it was absent. In addition, Experiment 3 revealed that-in contrast to previous claims-the activation of implicit causality is not a resource-consuming mental operation. Moreover, readers with higher and lower working memory capacities behaved differently in a dual-task situation. Higher span readers were more likely to use implicit causality when they had all their working memory resources at their disposal. Lower span readers showed the opposite pattern as they were more likely to use the implicit causality cue in the case of an additional working memory load. The results emphasize that both linguistic and cognitive factors mediate the impact of implicit causality on text comprehension. The implications of these results are discussed in terms of the ongoing controversies in the literature-that is, the focusing-integration debate and the debates on the source of implicit causality.

  14. Determination of influence factors and accident rates for the Armored Tractor/Safe Secure Trailer

    SciTech Connect

    Phillips, J.S.; Clauss, D.B.; Blower, D.F.

    1994-04-01

    Operating environments, such as road type, road location, and time of day, play an important role in the observed accident rates of heavy trucks used in general commerce. These same factors influence the accident rate of the Armored Tractor/Safe Secure Trailer (AT/SST) used by the Department of Energy to transport hazardous cargos within the continental United States. This report discusses the development of accident rate influence factors. These factors, based on heavy trucks used in general commerce, are used to modify the observed overall AT/SST accident rate to account for the different operating environments.

  15. Causal factors of corporate crime in Taiwan: qualitative and quantitative findings.

    PubMed

    Mon, Wei-Teh

    2002-04-01

    Street crimes are a primary concern of most criminologists in Taiwan. In recent years, however, crimes committed by corporations have increased greatly in this country. Employing the empirical approach to collect data about causal factors of corporate crime, the research presented in this article is the first systematic empirical study concerning corporate crime in Taiwan. The research sample was selected from a corporation with a criminal record of pollution caused by the release of toxic chemicals into the environment and a corporation with no criminal record. Questionnaire survey and interviews of corporate employees and managers were conducted, and secondary data were collected from official agencies. This research indicated the causal factors of corporate crime as follows: the failure of government regulation, lack of corporate self-regulation, lack of public concern about corporate crime, corporate mechanistic structure, and the low self-control tendency of corporate managers.

  16. Chemical factors affecting fission product transport in severe LMFBR accidents

    SciTech Connect

    Wichner, R.P.; Jolley, R.L.; Gat, U.; Rodgers, B.R.

    1984-10-01

    This study was performed as a part of a larger evaluation effort on LMFBR accident, source-term estimation. Purpose was to provide basic chemical information regarding fission product, sodium coolant, and structural material interactions required to perform estimation of fission product transport under LMFBR accident conditions. Emphasis was placed on conditions within the reactor vessel; containment vessel conditions are discussed only briefly.

  17. Cerebrovascular accidents in sickle cell disease: rates and risk factors.

    PubMed

    Ohene-Frempong, K; Weiner, S J; Sleeper, L A; Miller, S T; Embury, S; Moohr, J W; Wethers, D L; Pegelow, C H; Gill, F M

    1998-01-01

    Cerebrovascular accident (CVA) is a major complication of sickle cell disease. The incidence and mortality of and risk factors for CVA in sickle cell disease patients in the United States have been reported only in small patient samples. The Cooperative Study of Sickle Cell Disease collected clinical data on 4,082 sickle cell disease patients enrolled from 1978 to 1988. Patients were followed for an average of 5.2 +/- 2.0 years. Age-specific prevalence and incidence rates of CVA in patients with the common genotypes of sickle cell disease were determined, and the effects of hematologic and clinical events on the risk of CVA were analyzed. The highest rates of prevalence of CVA (4.01%) and incidence (0.61 per 100 patient-years) were in sickle cell anemia (SS) patients, but CVA occurred in all common genotypes. The incidence of infarctive CVA was lowest in SS patients 20 to 29 years of age and higher in children and older patients. Conversely, the incidence of hemorrhagic stroke in SS patients was highest among patients aged 20 to 29 years. Across all ages the mortality rate was 26% in the 2 weeks after hemorrhagic stroke. No deaths occurred after infarctive stroke. Risk factors for infarctive stroke included prior transient ischemic attack, low steady-state hemoglobin concentration and rate of and recent episode of acute chest syndrome, and elevated systolic blood pressure. Hemorrhagic stroke was associated with low steady-state hemoglobin and high leukocyte count.

  18. Accident-precipitating factors for crashes in turbine-powered general aviation aircraft.

    PubMed

    Boyd, Douglas D; Stolzer, Alan

    2016-01-01

    General aviation (14CFR Part 91) accounts for 83% of civil aviation fatalities. While much research has focused on accident causes/pilot demographics in this aviation sector, studies to identify factors leading up to the crash (accident-precipitating factors) are few. Such information could inform on pre-emptive remedial action. With this in mind and considering the paucity of research on turbine-powered aircraft accidents the study objectives were to identify accident-precipitating factors and determine if the accident rate has changed over time for such aircraft operating under 14CFR Part 91. The NTSB Access database was queried for accidents in airplanes (<12,501lb) powered by 1-2 turbine engines and occurring between 1989 and 2013. We developed and utilized an accident-precipitating factor taxonomy. Statistical analyses employed logistic regression, contingency tables and a generalized linear model with Poisson distribution. The "Checklist/Flight Manual Not Followed" was the most frequent accident-precipitating factor category and carried an excess risk (OR 2.34) for an accident with a fatal and/or serious occupant injury. This elevated risk reflected an over-representation of accidents with fatal and/or serious injury outcomes (p<0.001) in the "non-adherence to V Speeds" sub-category. For accidents grouped in the "Inadequate Pre-Flight Planning/Inspection/Procedure" the "inadequate weather planning" sub-category accounted (p=0.036) for the elevated risk (OR 2.22) of an accident involving fatal and/or serious injuries. The "Violation FARs/AIM Deviation" category was also associated with a greater risk for fatal and/or serious injury (OR 2.59) with "Descent below the MDA/failure to execute the missed approach" representing the largest sub-category. Accidents in multi-engine aircraft are more frequent than their single engine counterparts and the decline (50%) in the turbine aircraft accident rate over the study period was likely due, in part, to a 6-fold

  19. Accident-precipitating factors for crashes in turbine-powered general aviation aircraft.

    PubMed

    Boyd, Douglas D; Stolzer, Alan

    2016-01-01

    General aviation (14CFR Part 91) accounts for 83% of civil aviation fatalities. While much research has focused on accident causes/pilot demographics in this aviation sector, studies to identify factors leading up to the crash (accident-precipitating factors) are few. Such information could inform on pre-emptive remedial action. With this in mind and considering the paucity of research on turbine-powered aircraft accidents the study objectives were to identify accident-precipitating factors and determine if the accident rate has changed over time for such aircraft operating under 14CFR Part 91. The NTSB Access database was queried for accidents in airplanes (<12,501lb) powered by 1-2 turbine engines and occurring between 1989 and 2013. We developed and utilized an accident-precipitating factor taxonomy. Statistical analyses employed logistic regression, contingency tables and a generalized linear model with Poisson distribution. The "Checklist/Flight Manual Not Followed" was the most frequent accident-precipitating factor category and carried an excess risk (OR 2.34) for an accident with a fatal and/or serious occupant injury. This elevated risk reflected an over-representation of accidents with fatal and/or serious injury outcomes (p<0.001) in the "non-adherence to V Speeds" sub-category. For accidents grouped in the "Inadequate Pre-Flight Planning/Inspection/Procedure" the "inadequate weather planning" sub-category accounted (p=0.036) for the elevated risk (OR 2.22) of an accident involving fatal and/or serious injuries. The "Violation FARs/AIM Deviation" category was also associated with a greater risk for fatal and/or serious injury (OR 2.59) with "Descent below the MDA/failure to execute the missed approach" representing the largest sub-category. Accidents in multi-engine aircraft are more frequent than their single engine counterparts and the decline (50%) in the turbine aircraft accident rate over the study period was likely due, in part, to a 6-fold

  20. The contributions of sleep-related risk factors to diurnal car accidents.

    PubMed

    Lucidi, Fabio; Mallia, Luca; Violani, Cristiano; Giustiniani, Gabriele; Persia, Luca

    2013-03-01

    This study was intended to estimate the presence and number of individual sleep-related risk factors in a sample of diurnal car accidents and to analyze the extent to which these risk factors tended to be more represented in diurnal accidents involving only one vehicle, involving young drivers or occurring on non-urban roads. Two hundred fifty-three drivers involved in diurnal accidents were interviewed immediately after the accidents to assess their sleepiness-related personal conditions and the circumstances prior to the accident (i.e., individual sleep-related risk factors), such as poor sleep, changes in habitual sleeping patterns, prolonged wakefulness, self-reported acute sleepiness and daytime sleepiness, night-shift jobs and insomnia. A total of 12.3% of the drivers were classified as having at least one of the seven risk factors assessed in the study, supporting the general notion that drivers' sleepiness conditions are crucial, even in diurnal driving circumstances in which they are less likely to depend on chrono-biological processes. Furthermore, consistent with the guiding hypotheses, specific sleep-related risk factors were more evident in single (vs. multiple) car accidents, among young drivers and in car accidents occurring on non-urban roads. In summary, sleep-related risk factors seemed to have a negative impact on drivers' safety in circumstances of diurnal driving, especially when the accidents involved young individuals and occurred on non-urban roads. PMID:23246705

  1. The contributions of sleep-related risk factors to diurnal car accidents.

    PubMed

    Lucidi, Fabio; Mallia, Luca; Violani, Cristiano; Giustiniani, Gabriele; Persia, Luca

    2013-03-01

    This study was intended to estimate the presence and number of individual sleep-related risk factors in a sample of diurnal car accidents and to analyze the extent to which these risk factors tended to be more represented in diurnal accidents involving only one vehicle, involving young drivers or occurring on non-urban roads. Two hundred fifty-three drivers involved in diurnal accidents were interviewed immediately after the accidents to assess their sleepiness-related personal conditions and the circumstances prior to the accident (i.e., individual sleep-related risk factors), such as poor sleep, changes in habitual sleeping patterns, prolonged wakefulness, self-reported acute sleepiness and daytime sleepiness, night-shift jobs and insomnia. A total of 12.3% of the drivers were classified as having at least one of the seven risk factors assessed in the study, supporting the general notion that drivers' sleepiness conditions are crucial, even in diurnal driving circumstances in which they are less likely to depend on chrono-biological processes. Furthermore, consistent with the guiding hypotheses, specific sleep-related risk factors were more evident in single (vs. multiple) car accidents, among young drivers and in car accidents occurring on non-urban roads. In summary, sleep-related risk factors seemed to have a negative impact on drivers' safety in circumstances of diurnal driving, especially when the accidents involved young individuals and occurred on non-urban roads.

  2. Fatigue failure of metal components as a factor in civil aircraft accidents

    NASA Technical Reports Server (NTRS)

    Holshouser, W. L.; Mayner, R. D.

    1972-01-01

    A review of records maintained by the National Transportation Safety Board showed that 16,054 civil aviation accidents occurred in the United States during the 3-year period ending December 31, 1969. Material failure was an important factor in the cause of 942 of these accidents. Fatigue was identified as the mode of the material failures associated with the cause of 155 accidents and in many other accidents the records indicated that fatigue failures might have been involved. There were 27 fatal accidents and 157 fatalities in accidents in which fatigue failures of metal components were definitely identified. Fatigue failures associated with accidents occurred most frequently in landing-gear components, followed in order by powerplant, propeller, and structural components in fixed-wing aircraft and tail-rotor and main-rotor components in rotorcraft. In a study of 230 laboratory reports on failed components associated with the cause of accidents, fatigue was identified as the mode of failure in more than 60 percent of the failed components. The most frequently identified cause of fatigue, as well as most other types of material failures, was improper maintenance (including inadequate inspection). Fabrication defects, design deficiencies, defective material, and abnormal service damage also caused many fatigue failures. Four case histories of major accidents are included in the paper as illustrations of some of the factors invovled in fatigue failures of aircraft components.

  3. Investigation of Key Factors for Accident Severity at Railroad Grade Crossings by Using a Logit Model

    PubMed Central

    Hu, Shou-Ren; Li, Chin-Shang; Lee, Chi-Kang

    2009-01-01

    Although several studies have used logit or probit models and their variants to fit data of accident severity on roadway segments, few have investigated accident severity at a railroad grade crossing (RGC). Compared to accident risk analysis in terms of accident frequency and severity of a highway system, investigation of the factors contributing to traffic accidents at an RGC may be more complicated because of additional highway–railway interactions. Because the proportional odds assumption was violated while fitting cumulative logit modeled by the proportional odds models with stepwise variable selection to ordinal accident severity data collected at 592 RGCs in Taiwan, as suggested by Strokes et al. (2000, p. 249) a generalized logit model with stepwise variable selection was used instead to identify explanatory variables (factors or covariates) that were significantly associated with the severity of collisions. Hence, the fitted model was used to predict the level of accident severity, given a set of values in the explanatory variables. Number of daily trains, highway separation, number of daily trucks, obstacle detection device, and approaching crossing markings significantly affected levels of accident severity at an RGC (p-value = 0.0009, 0.0008, 0.0112, 0.0017, and 0.0003, respectively). Finally, marginal effect analysis on the number of daily trains and law enforcement camera was conducted to evaluate the effect of the number of daily trains and presence of a law enforcement camera on the potential accident severity. PMID:20161414

  4. Causal judgment from contingency information: the interpretation of factors common to all instances.

    PubMed

    White, P A

    2000-09-01

    Participants made judgments about stimulus materials in which there were 2 possible causes of an outcome. One of these was a common factor, a factor present in all instances presented for judgment, and the other was a positive covariate of the outcome. Instead of interpreting the positive covariate as the cause, participants consistently preferred an interpretation in which the common factor was the cause and the positive covariate enabled the cause to produce its effect. Participants' judgments of both interpretations were predicted by the proportion of instances that were confirmatory for the interpretation and not by deltaP. The findings support a hypothesis that people have a multirole conceptualization of causality including, in addition to the roles of cause and effect, that of an enabler, a factor the presence of which ensures that a thing is in a state of readiness to produce a particular effect.

  5. [Risk factors for accidents during sports while serving in German armed forces].

    PubMed

    Gundlach, N; Sammito, S; Böckelmann, I

    2012-03-01

    In the German Armed Forces sports activities should bring the benefits of good health and trained fitness which are the hallmarks of sportsmen. In order to achieve this aim it is important to avoid accidents which negate the benefit of sports. Until today there appear to be no studies in existence which demonstrate the risk factors of sports activities undertaken while in military service. Equivalent studies on civilian sport activities are scarcely comparable. To find out risk factors for accidents with any period of recovery we followed sports accidents while on duty in a German barracks with 4,300 soldiers over a two-year period. Additionally we asked about the time needed for recovery from each accident, parameters of lifestyle, the body mass index and the possibility of a nightshift before each accident. We examined a minimum of 410 accidents. We found associations between the accidents studied and particular risk factors, including doing sports more than two times a week, being active in a fitness or sports club, having the accident together with another sportsman and doing a nightshift before the day of the accident. Bad ground conditions contributed to a large number of accidents. A body mass index of 25 and higher had a significantly prolonged time for recovery. To avoid accidents, sport and ground conditions should be adapted to each other. In addition, overweight people are not only compromised for cardiovascular and neurological diseases but also have a higher risk of needing a prolonged time for recovery, thus it is important that overweight should be avoided and not only just be treated.

  6. Factors correlated with traffic accidents as a basis for evaluating Advanced Driver Assistance Systems.

    PubMed

    Staubach, Maria

    2009-09-01

    This study aims to identify factors which influence and cause errors in traffic accidents and to use these as a basis for information to guide the application and design of driver assistance systems. A total of 474 accidents were examined in depth for this study by means of a psychological survey, data from accident reports, and technical reconstruction information. An error analysis was subsequently carried out, taking into account the driver, environment, and vehicle sub-systems. Results showed that all accidents were influenced by errors as a consequence of distraction and reduced activity. For crossroad accidents, there were further errors resulting from sight obstruction, masked stimuli, focus errors, and law infringements. Lane departure crashes were additionally caused by errors as a result of masked stimuli, law infringements, expectation errors as well as objective and action slips, while same direction accidents occurred additionally because of focus errors, expectation errors, and objective and action slips. Most accidents were influenced by multiple factors. There is a safety potential for Advanced Driver Assistance Systems (ADAS), which support the driver in information assimilation and help to avoid distraction and reduced activity. The design of the ADAS is dependent on the specific influencing factors of the accident type. PMID:19664441

  7. Factors correlated with traffic accidents as a basis for evaluating Advanced Driver Assistance Systems.

    PubMed

    Staubach, Maria

    2009-09-01

    This study aims to identify factors which influence and cause errors in traffic accidents and to use these as a basis for information to guide the application and design of driver assistance systems. A total of 474 accidents were examined in depth for this study by means of a psychological survey, data from accident reports, and technical reconstruction information. An error analysis was subsequently carried out, taking into account the driver, environment, and vehicle sub-systems. Results showed that all accidents were influenced by errors as a consequence of distraction and reduced activity. For crossroad accidents, there were further errors resulting from sight obstruction, masked stimuli, focus errors, and law infringements. Lane departure crashes were additionally caused by errors as a result of masked stimuli, law infringements, expectation errors as well as objective and action slips, while same direction accidents occurred additionally because of focus errors, expectation errors, and objective and action slips. Most accidents were influenced by multiple factors. There is a safety potential for Advanced Driver Assistance Systems (ADAS), which support the driver in information assimilation and help to avoid distraction and reduced activity. The design of the ADAS is dependent on the specific influencing factors of the accident type.

  8. [Factors associated with work-related accidents in the informal commercial sector].

    PubMed

    Rios, Marcela Andrade; Nery, Adriana Alves; Rios, Polianna Alves Andrade; Casotti, Cezar Augusto; Cardoso, Jefferson Paixão

    2015-06-01

    This study aimed to estimate the incidence of non-fatal work-related accidents in the informal commercial sector and analyze associated socio-demographic, occupational, workplace, and health factors, in a cross-sectional survey of 434 workers in the business district of Jequié, Bahia State, Brazil, in 2013. Logistic regression was used to assess factors associated with accidents. Incidence of accidents in the previous 12 months was estimated at 32.3%, and multivariate analysis showed higher odds of accidents in male sex workers (OR = 1.61), young individuals (OR = 4.62), meat or poultry workers (OR = 9.55), and workers performing heavy physical work (OR = 1.71). The results show the need for public policies to prevent accidents in the informal commercial sector.

  9. [Factors associated with work-related accidents in the informal commercial sector].

    PubMed

    Rios, Marcela Andrade; Nery, Adriana Alves; Rios, Polianna Alves Andrade; Casotti, Cezar Augusto; Cardoso, Jefferson Paixão

    2015-06-01

    This study aimed to estimate the incidence of non-fatal work-related accidents in the informal commercial sector and analyze associated socio-demographic, occupational, workplace, and health factors, in a cross-sectional survey of 434 workers in the business district of Jequié, Bahia State, Brazil, in 2013. Logistic regression was used to assess factors associated with accidents. Incidence of accidents in the previous 12 months was estimated at 32.3%, and multivariate analysis showed higher odds of accidents in male sex workers (OR = 1.61), young individuals (OR = 4.62), meat or poultry workers (OR = 9.55), and workers performing heavy physical work (OR = 1.71). The results show the need for public policies to prevent accidents in the informal commercial sector. PMID:26200368

  10. Risk factors and musculoskeletal injuries associated with all-terrain vehicle accidents.

    PubMed

    Balthrop, Paul M; Nyland, John; Roberts, Craig S

    2009-02-01

    Accidents, injuries, and deaths sustained via all-terrain vehicle (ATV) use are on the rise. In addition to safe and proper ATV operation, accident-related risk factors include operator controllable behaviors such as helmet use, alcohol use, and deciding whether or not to carry a passenger. What the operator has little or no control over, however, is the inherently unstable ATV design with its narrow wheelbase, short turning radius, and high center of gravity, in addition to common use of low tire pressure to maximize maneuverability. These factors lead to musculoskeletal injuries that consist predominantly of extremity fractures, primarily through rollover events. There is a need for improved ATV operator safety education and more stringent regulations. The purpose of this review is to identify the accident and injury risk factors associated with ATV operation and to compare them with bicycle and motorcycle accident and injury risk factors to enable emergency medical professionals to develop better patient management and injury prevention strategies.

  11. Organisational Factors of Occupational Accidents with Movement Disturbance (OAMD) and Prevention

    PubMed Central

    LECLERCQ, Sylvie

    2014-01-01

    Workplace design and upkeep, or human factors, are frequently advanced for explaining so-called Occupational Slip, Trip and Fall Accidents (OSTFAs). Despite scientific progress, these accidents, and more broadly Occupational Accidents with Movement Disturbance (OAMDs), are also commonly considered to be “simple”. This paper aims to stimulate changes in such perceptions by focusing on organisational factors that often combine with other accident factors to cause movement disturbance and injury in work situations. These factors frequently lead to arbitration between production and safety, which involves implementation of controls by workers. These controls can lead to greater worker exposure to OAMD risk. We propose a model that focuses on such controls to account specifically for the need to confront production and safety logics within a company and to enhance the potential for appropriate prevention action. These are then integrated into the set of controls highlighted by work organisation model developed by the NIOSH. PMID:25345425

  12. Mapping historical information for better understanding the causality factors of past disasters

    NASA Astrophysics Data System (ADS)

    Boudou, Martin; Lang, Michel; Vinet, Freddy; Coeur, Denis

    2015-04-01

    The Flood Directive of 2007 promotes the use of historical information in order to mitigate the impact of future extreme events. According to this text, the study of past events offers new insights for better understanding the causality factors of a disaster, from hydrometeorological keys to socio-political repercussions of the flood. In this presentation we decided to focus on the study of factors leading to the exceptionality of a hydrological flood event. This aspect is regularly pointed out by the feedbacks carried out after a catastrophic event and remains a subject of debate for risk managers. The role of antecedent meteorological conditions is especially underestimated by local authorities. These factors can however be considered as a key issue to appreciate the exceptional character of a hydrological disaster. For example the 2013 June floods in France that affected the region of Pyrenees revealed the significant contribution of snow melting to the discharges recorded. In an article of 2014, Schröter et al. showed that the soil moisture can be considered as a key driver of the generalised flood hazard intensity that affected Germany over the same month of June 2013. With regard to these assessments, some considerations emerge. Does a diachronic appraisal of past disasters point out the main issues responsible for an exceptional flood hazard level? Is there common causality issues involved into these extreme hydrological events? In order to answer these questions this presentation proposes a comparative analysis of nine major floods that impacted the French territory during the XXth century (from 1910 to 2010). The set is composed by different flood typologies (from torrential events to floods resulting from groundwater level rising) so as to get a complete view of flood risk in France. The methodology proposed relies on a cartographic approach to highlight the causality factors of these past hydrological disasters. For instance, mapping the rainfall data

  13. [Cigarette smoking is the most important causal factor for developing chronic obstructive pulmonary disease (COPD)].

    PubMed

    Muro, Shigeo

    2011-10-01

    Cigarette smoking is the most important causal factor for developing chronic obstructive pulmonary disease(COPD). On the other hand, a substantial proportion of COPD cases suffer from obstructive disorder by other causes than smoking, especially among younger persons, females, and residents of developing countries. There are evidences that several rare genetic syndromes(such as alpha 1-antitrypsin deficiency) and occupational exposures as causes of COPD. Environmental tobacco smoke, biomass smoke, and dietary factors are likely causes of COPD, although their contribution is much less compared to active smoking. Smoking during pregnancy may also pose a risk for the fetus, by affecting lung growth and development in uterus. The quicker the smoking cessation is achieved, the more improvements in the lung functions the COPD patients can obtain. Smoking should be avoided as soon as possible in all the COPD subjects and those who are at risk for developing COPD.

  14. Accident investigation reporting deficiencies related to organizational factors in machinery space fires and explosions.

    PubMed

    Schröder-Hinrichs, Jens U; Baldauf, Michael; Ghirxi, Kevin T

    2011-05-01

    Careful accident investigation provides opportunities to review safety arrangements in socio-technical systems. There is consensus that human intervention is involved in the majority of accidents. Ever cautious of the consequences attributed to such a claim vis-à-vis the apportionment of blame, several authors have highlighted the importance of investigating organizational factors in this respect. Specific regulations to limit what were perceived as unsuitable organizational influences in shipping operations were adopted by the International Maritime Organization (IMO). Guidance is provided for the investigation of human and organizational factors involved in maritime accidents. This paper presents a review of 41 accident investigation reports related to machinery space fires and explosions. The objective was to find out if organizational factors are identified during maritime accident investigations. An adapted version of the Human Factor Analysis and Classification System (HFACS) with minor modifications related to machinery space features was used for this review. The results of the review show that organizational factors were not identified by maritime accident investigators to the extent expected had the IMO guidelines been observed. Instead, contributing factors at the lower end of organizational echelons are over-represented. PMID:21376918

  15. [Spatial and temporal changes of emerging environmental pollution accidents and impact factors in China].

    PubMed

    Li, Jing; Lü, Yong-long; He, Gui-zhen; Wang, Tie-yu; Luo, Wei; Shi, Ya-juan

    2008-09-01

    Based on environmental statistics data from 1993 to 2005, spatial distribution and temporal tendency of the environmental pollution and destruction accidents and their external causes were analyzed by using GIS and non-parametric correlation methods. It was concluded that (1) during the study period, annual environmental pollution accidents was maximally 3001 times in 1994 and minimally 1406 in 2005, while the frequency decreased in general. In addition, water and air accidents occupied the most; (2) environmental pollution and destruction accidents centralized in southeast and middle parts of China, mainly in Hunan, Sichuan, and Guangxi; (3) factors including population, GDP, company number and industrial waste water discharge had positive impacts on frequency of environmental pollution and destruction accidents, while in developed provinces the frequency was only correlated with company number.

  16. Study of Psycho-Social Factors Affecting Traffic Accidents Among Young Boys in Tehran

    PubMed Central

    Javadi, Seyyed Mohammad Hossein; Fekr Azad, Hossein; Tahmasebi, Siyamak; Rafiei, Hassan; Rahgozar, Mehdi; Tajlili, Alireza

    2015-01-01

    Background: Unprecedented growth of fatalities due to traffic accidents in the recent years has raised great concerns and efforts of authorities in order to identify and control the causes of these accidents. Objectives: In the present study, the contribution of psychological, social, demographic, environmental and behavioral factors on traffic accidents was studied for young boys in Tehran, emphasizing the importance of psychosocial factors. Patients and Methods: The design of the present study was quantitative (correlational) in which a sample population including 253 boys from Tehran (Iran) with an age range of 18 to 24 who had been referred to insurance institutions, hospitals, correctional facilities as well as prisons, were selected using stratified cluster sampling during the year 2013.The subjects completed the following questionnaires: demographic, general health, lifestyle, Manchester Driving Behavior Questionnaire (MDBQ), young parenting, and NEO-Five Factor Inventory (NEO-FFI). For data analysis, descriptive statistics, correlation coefficient, and inferential statistics including simultaneous regression, stepwise regression, and structural equations modeling were used. Results: The findings indicated that in the psychosocial model of driving behavior (including lapses, mistakes, and intentional violations) and accidents, psychological factors, depression (P < 0.02), personality trait of conscientiousness (P < 0.02), failure schema due to the parenting style of mother (P = 0.001), and perception of police commands (P < 0.002), played an important role in predicting driving behavior. Among social factors, perception of police regulations (P = 0.003), had an important effect on violations and mistakes. Among environmental and behavioral factors, major factors such as driving age (P = 0.001), drug and alcohol use (P = 0.001), having driver’s license (P = 0.013), records of imprisonment or committing a crime (P = 0.012) were also able to predict

  17. Analysing factors related to slipping, stumbling, and falling accidents at work: Application of data mining methods to Finnish occupational accidents and diseases statistics database.

    PubMed

    Nenonen, Noora

    2013-03-01

    The utilisation of data mining methods has become common in many fields. In occupational accident analysis, however, these methods are still rarely exploited. This study applies methods of data mining (decision tree and association rules) to the Finnish national occupational accidents and diseases statistics database to analyse factors related to slipping, stumbling, and falling (SSF) accidents at work from 2006 to 2007. SSF accidents at work constitute a large proportion (22%) of all accidents at work in Finland. In addition, they are more likely to result in longer periods of incapacity for work than other workplace accidents. The most important factor influencing whether or not an accident at work is related to SSF is the specific physical activity of movement. In addition, the risk of SSF accidents at work seems to depend on the occupation and the age of the worker. The results were in line with previous research. Hence the application of data mining methods was considered successful. The results did not reveal anything unexpected though. Nevertheless, because of the capability to illustrate a large dataset and relationships between variables easily, data mining methods were seen as a useful supplementary method in analysing occupational accident data.

  18. Future Integrated Systems Concept for Preventing Aircraft Loss-of-Control Accidents

    NASA Technical Reports Server (NTRS)

    Belcastro, Christine M.; Jacobson, Steven r.

    2010-01-01

    Loss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. This paper presents future system concepts and research directions for preventing aircraft loss-of-control accidents.

  19. Causal Factors of Weld Porosity in Gas Tungsten Arc Welding of Powder Metallurgy Produced Titanium Alloys

    SciTech Connect

    Muth, Thomas R; Yamamoto, Yukinori; Frederick, David Alan; Contescu, Cristian I; Chen, Wei; Lim, Yong Chae; Peter, William H; Feng, Zhili

    2013-01-01

    ORNL undertook an investigation using gas tungsten arc (GTA) welding on consolidated powder metallurgy (PM) titanium (Ti) plate, to identify the causal factors behind observed porosity in fusion welding. Tramp element compounds of sodium and magnesium, residual from the metallothermic reduction of titanium chloride used to produce the titanium, were remnant in the starting powder and were identified as gas forming species. PM-titanium made from revert scrap where sodium and magnesium were absent, showed fusion weld porosity, although to a lesser degree. We show that porosity was attributable to hydrogen from adsorbed water on the surface of the powders prior to consolidation. The removal / minimization of both adsorbed water on the surface of titanium powder and the residues from the reduction process prior to consolidation of titanium powders, are critical to achieve equivalent fusion welding success similar to that seen in wrought titanium produced via the Kroll process.

  20. Key factors contributing to accident severity rate in construction industry in Iran: a regression modelling approach.

    PubMed

    Soltanzadeh, Ahmad; Mohammadfam, Iraj; Moghimbeigi, Abbas; Ghiasvand, Reza

    2016-03-01

    Construction industry involves the highest risk of occupational accidents and bodily injuries, which range from mild to very severe. The aim of this cross-sectional study was to identify the factors associated with accident severity rate (ASR) in the largest Iranian construction companies based on data about 500 occupational accidents recorded from 2009 to 2013. We also gathered data on safety and health risk management and training systems. Data were analysed using Pearson's chi-squared coefficient and multiple regression analysis. Median ASR (and the interquartile range) was 107.50 (57.24- 381.25). Fourteen of the 24 studied factors stood out as most affecting construction accident severity (p<0.05). These findings can be applied in the design and implementation of a comprehensive safety and health risk management system to reduce ASR. PMID:27092639

  1. Research misconduct and data fraud in clinical trials: prevalence and causal factors.

    PubMed

    George, Stephen L

    2016-02-01

    The disclosure of cases of research misconduct in clinical trials, conventionally defined as fabrication, falsification or plagiarism, has been a disturbingly common phenomenon in recent years. Such cases can potentially harm patients enrolled on the trials in question or patients treated based on the results of those trials and can seriously undermine the scientific and public trust in the validity of clinical trial results. Here, I review what is known about the prevalence of research misconduct in general and the contributing or causal factors leading to the misconduct. The evidence on prevalence is unreliable and fraught with definitional problems and with study design issues. Nevertheless, the evidence taken as a whole seems to suggest that cases of the most serious types of misconduct, fabrication and falsification (i.e., data fraud), are relatively rare but that other types of questionable research practices are quite common. There have been many individual, institutional and scientific factors proposed for misconduct but, as is the case with estimates of prevalence, reliable empirical evidence on the strength and relative importance of these factors is lacking. However, it seems clear that the view of misconduct as being simply the result of aberrant or self-delusional personalities likely underestimates the effect of other important factors and inhibits the development of effective prevention strategies. PMID:26289019

  2. Research misconduct and data fraud in clinical trials: prevalence and causal factors.

    PubMed

    George, Stephen L

    2016-02-01

    The disclosure of cases of research misconduct in clinical trials, conventionally defined as fabrication, falsification or plagiarism, has been a disturbingly common phenomenon in recent years. Such cases can potentially harm patients enrolled on the trials in question or patients treated based on the results of those trials and can seriously undermine the scientific and public trust in the validity of clinical trial results. Here, I review what is known about the prevalence of research misconduct in general and the contributing or causal factors leading to the misconduct. The evidence on prevalence is unreliable and fraught with definitional problems and with study design issues. Nevertheless, the evidence taken as a whole seems to suggest that cases of the most serious types of misconduct, fabrication and falsification (i.e., data fraud), are relatively rare but that other types of questionable research practices are quite common. There have been many individual, institutional and scientific factors proposed for misconduct but, as is the case with estimates of prevalence, reliable empirical evidence on the strength and relative importance of these factors is lacking. However, it seems clear that the view of misconduct as being simply the result of aberrant or self-delusional personalities likely underestimates the effect of other important factors and inhibits the development of effective prevention strategies.

  3. Determining the direction of causality between psychological factors and aircraft noise annoyance.

    PubMed

    Kroesen, Maarten; Molin, Eric J E; van Wee, Bert

    2010-01-01

    In this paper, an attempt is made to establish the direction of causality between a range of psychological factors and aircraft noise annoyance. For this purpose, a panel model was estimated within a structural equation modeling approach. Data were gathered from two surveys conducted in April 2006 and April 2008, respectively, among the same residents living within the 45 Level day-evening-night contour of Amsterdam Airport Schiphol, the largest airport in the Netherlands (n=250). A surprising result is that none of the paths from the psychological factors to aircraft noise annoyance were found to be significant. Yet 2 effects were significant the other way around: (1) from 'aircraft noise annoyance' to 'concern about the negative health effects of noise' and (2) from 'aircraft noise annoyance' to 'belief that noise can be prevented.' Hence aircraft noise annoyance measured at time 1 contained information that can effectively explain changes in these 2 variables at time 2, while controlling for their previous values. Secondary results show that (1) aircraft noise annoyance is very stable through time and (2) that changes in aircraft noise annoyance and the identified psychological factors are correlated.

  4. The Causal Factors Associated with the Loving Care of the Mothers of Children with Multiple Disabilities

    PubMed Central

    Sadati, Ahmad Kalateh; Salehzade, Hamze; Hemmati, Soroor; Darvish, Manijeh; Heydari, Seyed Taghi; Tabrizi, Reza

    2015-01-01

    Background: Families with disabled children need more psycho-social considerations. Motherhood care of the children with multiple disabilities is difficult. Due to its importance, the aim of this study was to investigate the causal factors affecting loving care of mothers of children with multiple disabilities. Methods: The study used a cross-sectional method in which 75 mothers of exceptional children with multiple disabilities (physical and mental) in elementary schools in Shiraz, Iran. The data were collected through questionnaires which, besides demographical factors, evaluated the relationship between mothers’ loving care of children with multiple disabilities and four other variables including purpose in life, life satisfaction, religious attitude, and sense of coherence. Mann-Whitney U was used for comparison between mothers’ loving care and other variables. Results: Results revealed that demographic variables did not have a significant relationship with loving care. In the case of social variables, there was a significant relationship between mothers’ loving care and purpose in life (P<0.001), religious attitude (P<0.001), and life satisfaction (P=0.01). Conclusion: Motherhood care of disabled children is a unique phenomenon which is due to attachment of mother-child situation. Nevertheless, these mothers are vulnerable and marginalized people who need more attention and social supports provided by related governmental institutions and also NGOs actors. PMID:26448958

  5. Adenotonsillar hypertrophy: a precipitating factor of cerebrovascular accident in a child with sickle cell anemia.

    PubMed

    Wali, Y A; al-Lamki, Z; Soliman, H; al-Okbi, H

    2000-08-01

    Cerebrovascular accident is one of the most serious complications of sickle cell anemia. The specific factors that predispose patients with sickle cell anemia to stroke are increased disease severity, higher baseline white blood cell count and lower baseline hematocrits. Likewise the presence of a co-existent alpha thalassemia trait and/or high fetal hemoglobin (HbF%) may reduce the risk. We report a child with sickle cell anemia and marked adenotonsillar hypertrophy resulting in obstructive sleep apnea syndrome. There was no other known risk factor for developing cerebrovascular accident in this child during her hospitalization for adenotonsillectomy.

  6. [Risk factors associated with road accidents among young people in Tuscany (Italy): a cross sectional study].

    PubMed

    Innocenti, Francesco; Voller, Fabio; Berti, Alice; Silvestri, Caterina

    2013-01-01

    In most countries, national statistics institutes either do not measure or underestimate the impact of behavioral aspects as causes of road accidents. To bridge this gap, the Regional Health Agency of Tuscany (Italy) created the EDIT project, which evaluates driving behaviors and other lifestyle risk factors in a sample of secondary school students. Study results show that driving while under the influence of alcohol or drugs or while being distracted by cigarette smoking or the use of mobile phones are the risk factors most frequently associated with traffic accidents. PMID:23903036

  7. Triglyceride-rich lipoproteins as a causal factor for cardiovascular disease

    PubMed Central

    Toth, Peter P

    2016-01-01

    Approximately 25% of US adults are estimated to have hypertriglyceridemia (triglyceride [TG] level ≥150 mg/dL [≥1.7 mmol/L]). Elevated TG levels are associated with increased cardiovascular disease (CVD) risk, and severe hypertriglyceridemia (TG levels ≥500 mg/dL [≥5.6 mmol/L]) is a well-established risk factor for acute pancreatitis. Plasma TG levels correspond to the sum of the TG content in TG-rich lipoproteins (TRLs; ie, very low-density lipoproteins plus chylomicrons) and their remnants. There remains some uncertainty regarding the direct causal role of TRLs in the progression of atherosclerosis and CVD, with cardiovascular outcome studies of TG-lowering agents, to date, having produced inconsistent results. Although low-density lipoprotein cholesterol (LDL-C) remains the primary treatment target to reduce CVD risk, a number of large-scale epidemiological studies have shown that elevated TG levels are independently associated with increased incidence of cardiovascular events, even in patients treated effectively with statins. Genetic studies have further clarified the causal association between TRLs and CVD. Variants in several key genes involved in TRL metabolism are strongly associated with CVD risk, with the strength of a variant’s effect on TG levels correlating with the magnitude of the variant’s effect on CVD. TRLs are thought to contribute to the progression of atherosclerosis and CVD via a number of direct and indirect mechanisms. They directly contribute to intimal cholesterol deposition and are also involved in the activation and enhancement of several proinflammatory, proapoptotic, and procoagulant pathways. Evidence suggests that non-high-density lipoprotein cholesterol, the sum of the total cholesterol carried by atherogenic lipoproteins (including LDL, TRL, and TRL remnants), provides a better indication of CVD risk than LDL-C, particularly in patients with hypertriglyceridemia. This article aims to provide an overview of the

  8. Risk factors for traffic accidents in Bangkok Metropolis: a case-reference study.

    PubMed

    Na Ayuthya, R S; Böhning, D

    1997-12-01

    It was aimed to study injures from road traffic accidents in Bangkok Metropolis and identify patients' characteristics as well as to search for risk factors for traffic accidents leading to hospitalization. The study included 346 in-patient cases suffering injuries from road traffic accidents in Bangkok Metropolis. The patients were recruited during a period of 4 months of the year 1992 from five hospitals in various areas of Bangkok which were judged to be representative for Bangkok Metropolis. Using the method of case-reference, relative risk could be estimated for various exposure factors. Most of the patients drove a motorcycle, had their license for only a short period, and drove more than 5 hours a day. About one third of the patients were under the influence of alcohol. The traffic accident characteristics were that they occurred mainly at night time with the peak between 21.00 and 24.00 hours. About 90% of all traffic accidents occurred during the rainy season and most of them occurred near to road junctions. Reference data was available for some variables and the following risk group could be identified: RR (male-age 20-24) = 17.06 (8.8-33.9), RR (single-marital status) = 2.25 (1.7-3.1), RR (primary-education) = 6.2 (2.9-12.6), RR (unskilled labourer-occupation) = 3.91 (2.7-5.9), RR (salesperson-occupation) = 3.34 (2.2-5.0). PMID:9656420

  9. Male longevity in Sardinia, a review of historical sources supporting a causal link with dietary factors.

    PubMed

    Pes, G M; Tolu, F; Dore, M P; Sechi, G P; Errigo, A; Canelada, A; Poulain, M

    2015-04-01

    The identification of a hot spot of exceptional longevity, the Longevity Blue Zone (LBZ), in the mountain population of Sardinia has aroused considerable interest toward its traditional food as one of the potential causal factors. This preliminary study on the traditional Sardinian diet has been supported by the literature available, which has been carefully reviewed and compared. Up to a short time ago, the LBZ population depended mostly upon livestock rearing, and consumption of animal-derived foods was relatively higher than in the rest of the island. The nutrition transition (NT) in urbanized and lowland areas began in the mid-1950s, fueled by economic development, whereas in the LBZ it started later owing to prolonged resistance to change by a society organized around a rather efficient pastoral economy. Even nowadays a large proportion of the population in this area still follows the traditional diet based on cereal-derived foods and dairy products. The LBZ cohorts comprising individuals who were of a mature age when NT began may have benefited both from the high-quality, albeit rather monotonous, traditional diet to which they had been exposed most of their life and from the transitional diet, which introduced positive changes such as more variety, increased consumption of fruits and vegetables and moderate meat intake. It could be speculated that these changes may have brought substantial health benefits to this particular aging group, which was in need of nutrient-rich food at this specific time in life, thereby resulting in a decreased mortality risk and, in turn, life-span extension. PMID:25369832

  10. Male longevity in Sardinia, a review of historical sources supporting a causal link with dietary factors.

    PubMed

    Pes, G M; Tolu, F; Dore, M P; Sechi, G P; Errigo, A; Canelada, A; Poulain, M

    2015-04-01

    The identification of a hot spot of exceptional longevity, the Longevity Blue Zone (LBZ), in the mountain population of Sardinia has aroused considerable interest toward its traditional food as one of the potential causal factors. This preliminary study on the traditional Sardinian diet has been supported by the literature available, which has been carefully reviewed and compared. Up to a short time ago, the LBZ population depended mostly upon livestock rearing, and consumption of animal-derived foods was relatively higher than in the rest of the island. The nutrition transition (NT) in urbanized and lowland areas began in the mid-1950s, fueled by economic development, whereas in the LBZ it started later owing to prolonged resistance to change by a society organized around a rather efficient pastoral economy. Even nowadays a large proportion of the population in this area still follows the traditional diet based on cereal-derived foods and dairy products. The LBZ cohorts comprising individuals who were of a mature age when NT began may have benefited both from the high-quality, albeit rather monotonous, traditional diet to which they had been exposed most of their life and from the transitional diet, which introduced positive changes such as more variety, increased consumption of fruits and vegetables and moderate meat intake. It could be speculated that these changes may have brought substantial health benefits to this particular aging group, which was in need of nutrient-rich food at this specific time in life, thereby resulting in a decreased mortality risk and, in turn, life-span extension.

  11. Psychophysiological and other factors affecting human performance in accident prevention and investigation. [Comparison of aviation with other industries

    SciTech Connect

    Klinestiver, L.R.

    1980-01-01

    Psychophysiological factors are not uncommon terms in the aviation incident/accident investigation sequence where human error is involved. It is highly suspect that the same psychophysiological factors may also exist in the industrial arena where operator personnel function; but, there is little evidence in literature indicating how management and subordinates cope with these factors to prevent or reduce accidents. It is apparent that human factors psychophysological training is quite evident in the aviation industry. However, while the industrial arena appears to analyze psychophysiological factors in accident investigations, there is little evidence that established training programs exist for supervisors and operator personnel.

  12. Risk factors affecting fatal bus accident severity: Their impact on different types of bus drivers.

    PubMed

    Feng, Shumin; Li, Zhenning; Ci, Yusheng; Zhang, Guohui

    2016-01-01

    While the bus is generally considered to be a relatively safe means of transportation, the property losses and casualties caused by bus accidents, especially fatal ones, are far from negligible. The reasons for a driver to incur fatalities are different in each case, and it is essential to discover the underlying risk factors of bus fatality severity for different types of drivers in order to improve bus safety. The current study investigates the underlying risk factors of fatal bus accident severity to different types of drivers in the U.S. by estimating an ordered logistic model. Data for the analysis are retrieved from the Buses Involved in Fatal Accidents (BIFA) database from the USA for the years 2006-2010. Accidents are divided into three levels by counting their equivalent fatalities, and the drivers are classified into three clusters by the K-means cluster analysis. The analysis shows that some risk factors have the same impact on different types of drivers, they are: (a) season; (b) day of week; (c) time period; (d) number of vehicles involved; (e) land use; (f) manner of collision; (g) speed limit; (h) snow or ice surface condition; (i) school bus; (j) bus type and seating capacity; (k) driver's age; (l) driver's gender; (m) risky behaviors; and (n) restraint system. Results also show that some risk factors only have impact on the "young and elder drivers with history of traffic violations", they are: (a) section type; (b) number of lanes per direction; (c) roadway profile; (d) wet road surface; and (e) cyclist-bus accident. Notably, history of traffic violations has different impact on different types of bus drivers.

  13. Risk factors affecting fatal bus accident severity: Their impact on different types of bus drivers.

    PubMed

    Feng, Shumin; Li, Zhenning; Ci, Yusheng; Zhang, Guohui

    2016-01-01

    While the bus is generally considered to be a relatively safe means of transportation, the property losses and casualties caused by bus accidents, especially fatal ones, are far from negligible. The reasons for a driver to incur fatalities are different in each case, and it is essential to discover the underlying risk factors of bus fatality severity for different types of drivers in order to improve bus safety. The current study investigates the underlying risk factors of fatal bus accident severity to different types of drivers in the U.S. by estimating an ordered logistic model. Data for the analysis are retrieved from the Buses Involved in Fatal Accidents (BIFA) database from the USA for the years 2006-2010. Accidents are divided into three levels by counting their equivalent fatalities, and the drivers are classified into three clusters by the K-means cluster analysis. The analysis shows that some risk factors have the same impact on different types of drivers, they are: (a) season; (b) day of week; (c) time period; (d) number of vehicles involved; (e) land use; (f) manner of collision; (g) speed limit; (h) snow or ice surface condition; (i) school bus; (j) bus type and seating capacity; (k) driver's age; (l) driver's gender; (m) risky behaviors; and (n) restraint system. Results also show that some risk factors only have impact on the "young and elder drivers with history of traffic violations", they are: (a) section type; (b) number of lanes per direction; (c) roadway profile; (d) wet road surface; and (e) cyclist-bus accident. Notably, history of traffic violations has different impact on different types of bus drivers. PMID:26513334

  14. How Can Historical Understanding Best be Assessed? Use of Prediction Tasks To Assess How Students Understand the Role of Causal Factors that Produce Historical Events.

    ERIC Educational Resources Information Center

    Alonso-Tapia, Jesus; Villa, Jose Luis

    1999-01-01

    Examines the viability of using hypothetical problems that need the application of causal models for their solution as a method to assessing understanding in the social sciences. Explains that this method was used to describe how seventh-grade students understand causal factors affecting the "discovery and colonization of America." (CMK)

  15. Drug-disease association and drug-repositioning predictions in complex diseases using causal inference-probabilistic matrix factorization.

    PubMed

    Yang, Jihong; Li, Zheng; Fan, Xiaohui; Cheng, Yiyu

    2014-09-22

    The high incidence of complex diseases has become a worldwide threat to human health. Multiple targets and pathways are perturbed during the pathological process of complex diseases. Systematic investigation of complex relationship between drugs and diseases is necessary for new association discovery and drug repurposing. For this purpose, three causal networks were constructed herein for cardiovascular diseases, diabetes mellitus, and neoplasms, respectively. A causal inference-probabilistic matrix factorization (CI-PMF) approach was proposed to predict and classify drug-disease associations, and further used for drug-repositioning predictions. First, multilevel systematic relations between drugs and diseases were integrated from heterogeneous databases to construct causal networks connecting drug-target-pathway-gene-disease. Then, the association scores between drugs and diseases were assessed by evaluating a drug's effects on multiple targets and pathways. Furthermore, PMF models were learned based on known interactions, and associations were then classified into three types by trained models. Finally, therapeutic associations were predicted based upon the ranking of association scores and predicted association types. In terms of drug-disease association prediction, modified causal inference included in CI-PMF outperformed existing causal inference with a higher AUC (area under receiver operating characteristic curve) score and greater precision. Moreover, CI-PMF performed better than single modified causal inference in predicting therapeutic drug-disease associations. In the top 30% of predicted associations, 58.6% (136/232), 50.8% (31/61), and 39.8% (140/352) hit known therapeutic associations, while precisions obtained by the latter were only 10.2% (231/2264), 8.8% (36/411), and 9.7% (189/1948). Clinical verifications were further conducted for the top 100 newly predicted therapeutic associations. As a result, 21, 12, and 32 associations have been studied and

  16. Aetiological factors contributing to road traffic accidents in Riyadh City, Saudi Arabia.

    PubMed

    Nofal, F H; Saeed, A A; Anokute, C C

    1996-10-01

    The study analysed 13,390 police records of road traffic accidents (RTAs) covering a three and a half year period according to different suspected aetiological factors. The majority of the accidents were recorded for vehicles in good condition on well-paved straight roads with well-operating traffic light systems. Adverse weather conditions such as precipitation, fog and dust were of minimal importance, with most of the accidents being reported during sunny days during the rush period of 12 noon to 3 pm. Driver's error was identified as the main contributing factor in about two thirds of all RTAs mainly as reckless driving and excess speeding. About 27% of the drivers were professional drivers and 41% were in the age group 25-35 years in good health with no alcohol or drug intake. Hence, human errors may be attributed to carelessness, experience, lack of knowledge or attention, over-exhaustion or fatigue. The effects of physical stressors on performance of drivers need to be further explored and clarified but this need not underestimate the importance of vehicle and environment since most accidents are multifactoral and a slight change in them may effectively enhance perception and minimise personal error. Recommendations for remedial measures adopting an interdisciplinary approach are presented. PMID:8936950

  17. FACTORS RELATED TO MOTORCYCLE ACCIDENT RISK BEHAVIOR AMONG UNIVERSITY STUDENTS IN NORTHEASTERN THAILAND.

    PubMed

    Chumpawadee, Urai; Homchampa, Pissamai; Thongkrajai, Pramote; Suwanimitr, Amorn; Chadbunchachai, Witaya

    2015-07-01

    Young motorcycle drivers in Thailand are at high risk for road traffic accidents. We conducted this study to identify factors associated with motorcycle accident risk behavior (MARB). We studied 372 randomly selected university students aged 18-22 years (mean 20.2 years; women comprised 68.0% of our participants), who attend a government university in northeastern Thailand. Each student was asked to fill out a questionnaire asking about MARB and factors associated with this behavior. The respondents had an average of 6.2 years (SD+3.09) motorcycle driving experience, 72.3% had a motorcycle driver's license and 83.0% had accident insurance. The prevalence of self-reported motorcycle accident injuries was 42.7%. Their major MARB were using a telephone while driving (69.3%), speeding (45.4%), driving with more than one passenger (40.1%), drunk driving (22.1%), and not wearing a helmet (23.3%). Factors related to MARB were: gender, with men engaged in risky behavior more often than women (p < 0.05); duration of motorcycle driving--drivers with > 5 years experience were more likely to engage in risky behavior (p < 0.05); and knowledge of safe driving, those with a greater knowledge of safe driving were more likely to drive safely (p < 0.001). Having a greater awareness of MARB was associated with lower risk of engaging in risky behavior (p < 0.001). Students who engaged in risky behavior were more likely to view it as normal behavior (p < 0.001) and less likely to have adequate self-control (p < 0.001). Our findings indicate a need to strengthen accident prevention programs for university students in northeastern Thailand. PMID:26867401

  18. Deconstructing Constructivism: Modeling Causal Relationships Among Constructivist Learning Environment Factors and Student Outcomes in Introductory Chemistry

    NASA Astrophysics Data System (ADS)

    Komperda, Regis

    The purpose of this dissertation is to test a model of relationships among factors characterizing aspects of a student-centered constructivist learning environment and student outcomes of satisfaction and academic achievement in introductory undergraduate chemistry courses. Constructivism was chosen as the theoretical foundation for this research because of its widespread use in chemical education research and practice. In a constructivist learning environment the role of the teacher shifts from delivering content towards facilitating active student engagement in activities that encourage individual knowledge construction through discussion and application of content. Constructivist approaches to teaching introductory chemistry courses have been adopted by some instructors as a way to improve student outcomes, but little research has been done on the causal relationships among particular aspects of the learning environment and student outcomes. This makes it difficult for classroom teachers to know which aspects of a constructivist teaching approach are critical to adopt and which may be modified to better suit a particular learning environment while still improving student outcomes. To investigate a model of these relationships, a survey designed to measure student perceptions of three factors characterizing a constructivist learning environment in online courses was adapted for use in face-to-face chemistry courses. These three factors, teaching presence, social presence, and cognitive presence, were measured using a slightly modified version of the Community of Inquiry (CoI) instrument. The student outcomes investigated in this research were satisfaction and academic achievement, as measured by standardized American Chemical Society (ACS) exam scores and course grades. Structural equation modeling (SEM) was used to statistically model relationships among the three presence factors and student outcome variables for 391 students enrolled in six sections of a

  19. The Impact of School Leadership on School Level Factors: Validation of a Causal Model

    ERIC Educational Resources Information Center

    Kruger, Meta L.; Witziers, Bob; Sleegers, Peter

    2007-01-01

    This study aims to contribute to a better understanding of the antecedents and effects of educational leadership, and of the influence of the principal's leadership on intervening and outcome variables. A path analysis was conducted to test and validate a causal model. The results show no direct or indirect effects of educational leadership on…

  20. Crew Communication as a Factor in Aviation Accidents

    NASA Technical Reports Server (NTRS)

    Goguen, J.; Linde, C.; Murphy, M.

    1986-01-01

    The crew communication process is analyzed. Planning and explanation are shown to be well-structured discourse types, described by formal rules. These formal rules are integrated with those describing the other most important discourse type within the cockpit: the command-and-control speech act chain. The latter is described as a sequence of speech acts for making requests (including orders and suggestions), for making reports, for supporting or challenging statements, and for acknowledging previous speech acts. Mitigation level, a linguistic indication of indirectness and tentativeness in speech, was an important variable in several hypotheses, i.e., the speech of subordinates is more mitigated than the speech of superiors, the speech of all crewmembers is less mitigated when they know that they are in either a problem or emergency situation, and mitigation is a factor in failures of crewmembers to initiate discussion of new topics or have suggestions ratified by the captain. Test results also show that planning and explanation are more frequently performed by captains, are done more during crew- recognized problems, and are done less during crew-recognized emergencies. The test results also indicated that planning and explanation are more frequently performed by captains than by other crewmembers, are done more during crew-recognized problems, and are done less during-recognized emergencies.

  1. Human and organisational factors in maritime accidents: analysis of collisions at sea using the HFACS.

    PubMed

    Chauvin, Christine; Lardjane, Salim; Morel, Gaël; Clostermann, Jean-Pierre; Langard, Benoît

    2013-10-01

    Over the last decade, the shipping industry has implemented a number of measures aimed at improving its safety level (such as new regulations or new forms of team training). Despite this evolution, shipping accidents, and particularly collisions, remain a major concern. This paper presents a modified version of the Human Factors Analysis and Classification System, which has been adapted to the maritime context and used to analyse human and organisational factors in collisions reported by the Marine Accident and Investigation Branch (UK) and the Transportation Safety Board (Canada). The analysis shows that most collisions are due to decision errors. At the precondition level, it highlights the importance of the following factors: poor visibility and misuse of instruments (environmental factors), loss of situation awareness or deficit of attention (conditions of operators), deficits in inter-ship communications or Bridge Resource Management (personnel factors). At the leadership level, the analysis reveals the frequent planning of inappropriate operations and non-compliance with the Safety Management System (SMS). The Multiple Accident Analysis provides an important finding concerning three classes of accidents. Inter-ship communications problems and Bridge Resource Management deficiencies are closely linked to collisions occurring in restricted waters and involving pilot-carrying vessels. Another class of collisions is associated with situations of poor visibility, in open sea, and shows deficiencies at every level of the socio-technical system (technical environment, condition of operators, leadership level, and organisational level). The third class is characterised by non-compliance with the SMS. This study shows the importance of Bridge Resource Management for situations of navigation with a pilot on board in restricted waters. It also points out the necessity to investigate, for situations of navigation in open sea, the masters' decisions in critical conditions

  2. Factors affecting the probability of bus drivers being at-fault in bus-involved accidents.

    PubMed

    Goh, Kelvin; Currie, Graham; Sarvi, Majid; Logan, David

    2014-05-01

    Previous research has provided little insight into factors that influence the probability of bus drivers being at-fault in bus-involved accidents. In this study, an analysis was conducted on accident data compiled by a bus company that include an assessment on whether the bus driver was deemed by the company to hold primary responsibility for accident occurrence. Using a mixed logit modelling approach, roadway/environmental, vehicle and driver related variables that were identified to be influential were road type, speed limit, traffic/lighting conditions, bus priority, bus age/length and driver's age/gender/experience/historic at-fault accident record. Results were indicative of possible confined road-space issues that bus drivers face along routes with roadside traffic friction and point to the provision of exclusive right of way for buses as a possible way to address this. Results also suggest benefits in assigning routes comprising mainly divided roads as well as newer and shorter buses to less experienced drivers.

  3. Risk and preventive factors for fatalities in All-terrain Vehicle Accidents in New Zealand.

    PubMed

    Shulruf, Boaz; Balemi, Andrew

    2010-03-01

    All-Terrain Vehicles (ATVs) have been used in agriculture for a few decades now. Yet despite their invaluable contribution to the productivity of the agricultural industry they are associated with a large number of accidents, many of which result in a severe or fatal outcome. The main objective of this study was to identify the risk factors for ATV-related fatal injuries in order to support the design of effective interventions. Using data held by the Department of Labour, the current study analysed 355 cases of serious harm accidents associated with ATVs including 45 fatalities. The findings suggest that injuries are more likely to occur when accidents involve any of the following: children under the age of 10; four-wheel drive ATVs; driving downhill; driving on a sealed road; driving backwards; or if the ATV rolls sideways. A fatal outcome is more likely to occur when ATV accidents end up with the vehicle rolling over and pinning the driver underneath. Fatalities were also associated with injuries to the head, neck and chest. Being employed; and/or having formal training; and/or having brakes and tyres well maintained on the ATV; and/or having no fluid load on the ATV reduced the risk for fatality. Since the likelihood of a fatal outcome was found to be related to human behaviour and ATV rollover, it is suggested that interventions should mainly address these two issues.

  4. A causal examination of the effects of confounding factors on multimetric indices

    USGS Publications Warehouse

    Schoolmaster, Donald R.; Grace, James B.; Schweiger, E. William; Mitchell, Brian R.; Guntenspergen, Glenn R.

    2013-01-01

    The development of multimetric indices (MMIs) as a means of providing integrative measures of ecosystem condition is becoming widespread. An increasingly recognized problem for the interpretability of MMIs is controlling for the potentially confounding influences of environmental covariates. Most common approaches to handling covariates are based on simple notions of statistical control, leaving the causal implications of covariates and their adjustment unstated. In this paper, we use graphical models to examine some of the potential impacts of environmental covariates on the observed signals between human disturbance and potential response metrics. Using simulations based on various causal networks, we show how environmental covariates can both obscure and exaggerate the effects of human disturbance on individual metrics. We then examine from a causal interpretation standpoint the common practice of adjusting ecological metrics for environmental influences using only the set of sites deemed to be in reference condition. We present and examine the performance of an alternative approach to metric adjustment that uses the whole set of sites and models both environmental and human disturbance effects simultaneously. The findings from our analyses indicate that failing to model and adjust metrics can result in a systematic bias towards those metrics in which environmental covariates function to artificially strengthen the metric–disturbance relationship resulting in MMIs that do not accurately measure impacts of human disturbance. We also find that a “whole-set modeling approach” requires fewer assumptions and is more efficient with the given information than the more commonly applied “reference-set” approach.

  5. Assessing Interactive Causal Influence

    ERIC Educational Resources Information Center

    Novick, Laura R.; Cheng, Patricia W.

    2004-01-01

    The discovery of conjunctive causes--factors that act in concert to produce or prevent an effect--has been explained by purely covariational theories. Such theories assume that concomitant variations in observable events directly license causal inferences, without postulating the existence of unobservable causal relations. This article discusses…

  6. Limitations of risk analysis in the determination of medical factors in road vehicle accidents.

    PubMed

    Spencer, Michael B; Carter, Tim; Nicholson, Anthony N

    2004-01-01

    The purpose of risk analysis in the determination of medical factors in road vehicle accidents is to evaluate the risks that are associated with different strategies for accident reduction, so that the subsequent decision making process can be based on a best assessment of the likely benefits. However, it is vital to appreciate the limitations of such an approach, especially where the conclusions depend heavily on the accuracy of the assumptions made. In this paper the assumptions used in some recent analyses concerned with incapacitation, epilepsy, hypoglycaemia and psycho-active medication are explored, and the additional information required to reduce the uncertainty in the estimation of risk indicated. The conclusions from this analysis do not invalidate the use of risk assessment, but draw attention to its limitations and show how a sensitivity analysis can help to identify those areas where more precise information is needed before such an approach can be used confidently in a policy setting. PMID:14998267

  7. [Morphological verification problems of Chernobyl factor influence on the prostate of coalminers of Donbas--liquidators of Chernobyl accident].

    PubMed

    Danylov, Iu V; Motkov, K V; Shevchenko, T I

    2013-12-01

    Problem of a diagnostic of Chernobyl factor influences on different organs and systems of Chernobyl accident liquidators are remain actually until now. Though morbidly background which development at unfavorable work conditions in underground coalminers prevents from objective identification features of Chernobyl factor influences. The qualitative and quantitative histological and immunohistochemical law of morphogenesis changes in prostate of Donbas's coalminer-non-liquidators Chernobyl accident in comparison with the group of Donbas's coalminers-liquidators Chernobyl accident which we were stationed non determined problem. This reason stipulates to development and practical use of mathematical model of morphogenesis of a prostatic gland changes.

  8. [Morphological verification problems of Chernobyl factor influence on the testis of coal miners of Donbas-liquidators of Chernobyl accident].

    PubMed

    Danylov, Iu V; Motkov, K V; Shevchenko, T I

    2013-01-01

    Problem of a diagnostic of Chernobyl factor influences on different organs and systems of Chernobyl accident liquidators are remain actually until now. Though morbidly background which development at unfavorable work conditions in underground coalminers prevents from objective identification features of Chernobyl factor influences. The qualitative and quantitative histological and immunohistochemical law of morphogenesis changes in testis of Donbas's coalminer - non-liquidators Chernobyl accident in comparison with the group of Donbas's coalminers-liquidators Chernobyl accident, which we were stationed non determined problem. This reason stipulates to development and practical use of mathematical model of morphogenesis of a testis changes.

  9. Aviation occupant survival factors: an empirical study of the SQ006 accident.

    PubMed

    Chang, Yu-Hern; Yang, Hui-Hua

    2010-03-01

    We present an empirical study of Singapore Airline (SIA) flight SQ006 to illustrate the critical factors that influence airplane occupant survivability. The Fuzzy Delphi Method was used to identify and rank the survival factors that may reduce injury and fatality in potentially survivable accidents. This is the first attempt by a group from both the public and private sectors in Taiwan to focus on cabin-safety issues related to survival factors. We designed a comprehensive survey based on our discussions with aviation safety experts. We next designed an array of important cabin-safety dimensions and then investigated and selected the critical survival factors for each dimension. Our findings reveal important cabin safety and survivability information that should provide a valuable reference for developing and evaluating aviation safety programs. We also believe that the results will be practical for designing cabin-safety education material for air travelers. Finally, the major contribution of this research is that it has identified 47 critical factors that influence accident survivability; therefore, it may encourage improvements that will promote more successful cabin-safety management. PMID:20159096

  10. Granger causality revisited

    PubMed Central

    Friston, Karl J.; Bastos, André M.; Oswal, Ashwini; van Wijk, Bernadette; Richter, Craig; Litvak, Vladimir

    2014-01-01

    This technical paper offers a critical re-evaluation of (spectral) Granger causality measures in the analysis of biological timeseries. Using realistic (neural mass) models of coupled neuronal dynamics, we evaluate the robustness of parametric and nonparametric Granger causality. Starting from a broad class of generative (state-space) models of neuronal dynamics, we show how their Volterra kernels prescribe the second-order statistics of their response to random fluctuations; characterised in terms of cross-spectral density, cross-covariance, autoregressive coefficients and directed transfer functions. These quantities in turn specify Granger causality — providing a direct (analytic) link between the parameters of a generative model and the expected Granger causality. We use this link to show that Granger causality measures based upon autoregressive models can become unreliable when the underlying dynamics is dominated by slow (unstable) modes — as quantified by the principal Lyapunov exponent. However, nonparametric measures based on causal spectral factors are robust to dynamical instability. We then demonstrate how both parametric and nonparametric spectral causality measures can become unreliable in the presence of measurement noise. Finally, we show that this problem can be finessed by deriving spectral causality measures from Volterra kernels, estimated using dynamic causal modelling. PMID:25003817

  11. Granger causality revisited.

    PubMed

    Friston, Karl J; Bastos, André M; Oswal, Ashwini; van Wijk, Bernadette; Richter, Craig; Litvak, Vladimir

    2014-11-01

    This technical paper offers a critical re-evaluation of (spectral) Granger causality measures in the analysis of biological timeseries. Using realistic (neural mass) models of coupled neuronal dynamics, we evaluate the robustness of parametric and nonparametric Granger causality. Starting from a broad class of generative (state-space) models of neuronal dynamics, we show how their Volterra kernels prescribe the second-order statistics of their response to random fluctuations; characterised in terms of cross-spectral density, cross-covariance, autoregressive coefficients and directed transfer functions. These quantities in turn specify Granger causality - providing a direct (analytic) link between the parameters of a generative model and the expected Granger causality. We use this link to show that Granger causality measures based upon autoregressive models can become unreliable when the underlying dynamics is dominated by slow (unstable) modes - as quantified by the principal Lyapunov exponent. However, nonparametric measures based on causal spectral factors are robust to dynamical instability. We then demonstrate how both parametric and nonparametric spectral causality measures can become unreliable in the presence of measurement noise. Finally, we show that this problem can be finessed by deriving spectral causality measures from Volterra kernels, estimated using dynamic causal modelling.

  12. 49 CFR 225.12 - Rail Equipment Accident/Incident Reports alleging employee human factor as cause; Employee Human...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... employee human factor as cause; Employee Human Factor Attachment; notice to employee; employee supplement..., AND INVESTIGATIONS § 225.12 Rail Equipment Accident/Incident Reports alleging employee human factor as cause; Employee Human Factor Attachment; notice to employee; employee supplement. (a) Rail...

  13. 49 CFR 225.12 - Rail Equipment Accident/Incident Reports alleging employee human factor as cause; Employee Human...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... employee human factor as cause; Employee Human Factor Attachment; notice to employee; employee supplement..., AND INVESTIGATIONS § 225.12 Rail Equipment Accident/Incident Reports alleging employee human factor as cause; Employee Human Factor Attachment; notice to employee; employee supplement. (a) Rail...

  14. Assessing the spatial variability of weights of landslide causal factors in different regions from Romania, using logistic regression

    NASA Astrophysics Data System (ADS)

    Margarint, M. C.; Grozavu, A.; Patriche, C. V.

    2012-04-01

    Landslides represent a significant natural hazard in hilly areas of Romania which cause important damages. The scientific interest for landslide susceptibility mapping is quite recent and standardized through legislation. However, there is need for improving the methodology, in order for the susceptibility maps to constitute a sound basis for territorial planning. The logistic regression is one of the main statistical methods used for assessing terrain susceptibility for landsliding. There are different degrees of weighting the landslide causal factors mentioned in the scientific literature, but with large variations. This study aims to identify the range of variation of landslide causal factors for different regions in Romania. The following factors were taken into consideration: slope angle, terrain altitude, terrain curvature (mean, plan and profile), soil type, lithologic class, land use, distance from drainage network and roads, mean annual precipitations. Four square perimeters of 15x15 km were chosen from representative regions in terms of spatial extent of landslides: two situated in the central-northern part of the Moldavian Plateau, one in the Transylvania Depression and one in the Moldavian Subcarpathians. The logistic regression was applied separately for the four sectors. In order to monitor the differences in the final results, numerous attempts have been made, starting from landslides polygons acquired from both the topographic maps at scale 1:25.000 (1984-1985 edition) and the ortophotoimages (2005-2006). The other elements were acquired from cartographic materials at appropriate scales, according the international methodology. The data integration was accomplished in the georeferenced environment provided by TNTMips 6.9 ArcGIS 9.3 and SAGA 2.0.8 software packages, while the statistical analysis was performed using Excel 2003 and XLSTAT 2010 trial version. Maps for all landslide causal factors were achieved for each perimeter. The logistic

  15. Causes and risk factors for fatal accidents in non-commercial twin engine piston general aviation aircraft.

    PubMed

    Boyd, Douglas D

    2015-04-01

    Accidents in twin-engine aircraft carry a higher risk of fatality compared with single engine aircraft and constitute 9% of all general aviation accidents. The different flight profile (higher airspeed, service ceiling, increased fuel load, and aircraft yaw in engine failure) may make comparable studies on single-engine aircraft accident causes less relevant. The objective of this study was to identify the accident causes for non-commercial operations in twin engine aircraft. A NTSB accident database query for accidents in twin piston engine airplanes of 4-8 seat capacity with a maximum certified weight of 3000-8000lbs. operating under 14CFR Part 91 for the period spanning 2002 and 2012 returned 376 accidents. Accident causes and contributing factors were as per the NTSB final report categories. Total annual flight hour data for the twin engine piston aircraft fleet were obtained from the FAA. Statistical analyses employed Chi Square, Fisher's Exact and logistic regression analysis. Neither the combined fatal/non-fatal accident nor the fatal accident rate declined over the period spanning 2002-2012. Under visual weather conditions, the largest number, n=27, (27%) of fatal accidents was attributed to malfunction with a failure to follow single engine procedures representing the most common contributing factor. In degraded visibility, poor instrument approach procedures resulted in the greatest proportion of fatal crashes. Encountering thunderstorms was the most lethal of all accident causes with all occupants sustaining fatal injuries. At night, a failure to maintain obstacle/terrain clearance was the most common accident cause leading to 36% of fatal crashes. The results of logistic regression showed that operations at night (OR 3.7), off airport landings (OR 14.8) and post-impact fire (OR 7.2) all carried an excess risk of a fatal flight. This study indicates training areas that should receive increased emphasis for twin-engine training/recency. First, increased

  16. Causes and risk factors for fatal accidents in non-commercial twin engine piston general aviation aircraft.

    PubMed

    Boyd, Douglas D

    2015-04-01

    Accidents in twin-engine aircraft carry a higher risk of fatality compared with single engine aircraft and constitute 9% of all general aviation accidents. The different flight profile (higher airspeed, service ceiling, increased fuel load, and aircraft yaw in engine failure) may make comparable studies on single-engine aircraft accident causes less relevant. The objective of this study was to identify the accident causes for non-commercial operations in twin engine aircraft. A NTSB accident database query for accidents in twin piston engine airplanes of 4-8 seat capacity with a maximum certified weight of 3000-8000lbs. operating under 14CFR Part 91 for the period spanning 2002 and 2012 returned 376 accidents. Accident causes and contributing factors were as per the NTSB final report categories. Total annual flight hour data for the twin engine piston aircraft fleet were obtained from the FAA. Statistical analyses employed Chi Square, Fisher's Exact and logistic regression analysis. Neither the combined fatal/non-fatal accident nor the fatal accident rate declined over the period spanning 2002-2012. Under visual weather conditions, the largest number, n=27, (27%) of fatal accidents was attributed to malfunction with a failure to follow single engine procedures representing the most common contributing factor. In degraded visibility, poor instrument approach procedures resulted in the greatest proportion of fatal crashes. Encountering thunderstorms was the most lethal of all accident causes with all occupants sustaining fatal injuries. At night, a failure to maintain obstacle/terrain clearance was the most common accident cause leading to 36% of fatal crashes. The results of logistic regression showed that operations at night (OR 3.7), off airport landings (OR 14.8) and post-impact fire (OR 7.2) all carried an excess risk of a fatal flight. This study indicates training areas that should receive increased emphasis for twin-engine training/recency. First, increased

  17. Causal and causally separable processes

    NASA Astrophysics Data System (ADS)

    Oreshkov, Ognyan; Giarmatzi, Christina

    2016-09-01

    The idea that events are equipped with a partial causal order is central to our understanding of physics in the tested regimes: given two pointlike events A and B, either A is in the causal past of B, B is in the causal past of A, or A and B are space-like separated. Operationally, the meaning of these order relations corresponds to constraints on the possible correlations between experiments performed in the vicinities of the respective events: if A is in the causal past of B, an experimenter at A could signal to an experimenter at B but not the other way around, while if A and B are space-like separated, no signaling is possible in either direction. In the context of a concrete physical theory, the correlations compatible with a given causal configuration may obey further constraints. For instance, space-like correlations in quantum mechanics arise from local measurements on joint quantum states, while time-like correlations are established via quantum channels. Similarly to other variables, however, the causal order of a set of events could be random, and little is understood about the constraints that causality implies in this case. A main difficulty concerns the fact that the order of events can now generally depend on the operations performed at the locations of these events, since, for instance, an operation at A could influence the order in which B and C occur in A’s future. So far, no formal theory of causality compatible with such dynamical causal order has been developed. Apart from being of fundamental interest in the context of inferring causal relations, such a theory is imperative for understanding recent suggestions that the causal order of events in quantum mechanics can be indefinite. Here, we develop such a theory in the general multipartite case. Starting from a background-independent definition of causality, we derive an iteratively formulated canonical decomposition of multipartite causal correlations. For a fixed number of settings and

  18. Effective Factors in Severity of Traffic Accident-Related Traumas; an Epidemiologic Study Based on the Haddon Matrix

    PubMed Central

    Masoumi, Kambiz; Forouzan, Arash; Barzegari, Hassan; Asgari Darian, Ali; Rahim, Fakher; Zohrevandi, Behzad; Nabi, Somayeh

    2016-01-01

    Introduction: Traffic accidents are the 8th cause of mortality in different countries and are expected to rise to the 3rd rank by 2020. Based on the Haddon matrix numerous factors such as environment, host, and agent can affect the severity of traffic-related traumas. Therefore, the present study aimed to evaluate the effective factors in severity of these traumas based on Haddon matrix. Methods: In the present 1-month cross-sectional study, all the patients injured in traffic accidents, who were referred to the ED of Imam Khomeini and Golestan Hospitals, Ahvaz, Iran, during March 2013 were evaluated. Based on the Haddon matrix, effective factors in accident occurrence were defined in 3 groups of host, agent, and environment. Demographic data of the patients and data regarding Haddon risk factors were extracted and analyzed using SPSS version 20. Results: 700 injured people with the mean age of 29.66 ± 12.64 years (3-82) were evaluated (92.4% male). Trauma mechanism was car-pedestrian in 308 (44%) of the cases and car-motorcycle in 175 (25%). 610 (87.1%) cases were traffic accidents and 371 (53%) occurred in the time between 2 pm and 8 pm. Violation of speed limit was the most common violation with 570 (81.4%) cases, followed by violation of right-of-way in 57 (8.1%) patients. 59.9% of the severe and critical injuries had occurred on road accidents, while 61.3% of the injuries caused by traffic accidents were mild to moderate (p < 0.001). The most common mechanisms of trauma for critical injuries were rollover (72.5%), motorcycle-pedestrian (23.8%), and car-motorcycle (13.14%) accidents (p < 0.001). Conclusion: Based on the results of the present study, the most important effective factors in severity of traffic accident-related traumas were age over 50, not using safety tools, and undertaking among host-related factors; insufficient environment safety, road accidents and time between 2 pm and 8 pm among environmental factors; and finally, rollover, car

  19. Quantification method analysis of the relationship between occupant injury and environmental factors in traffic accidents.

    PubMed

    Ju, Yong Han; Sohn, So Young

    2011-01-01

    Injury analysis following a vehicle crash is one of the most important research areas. However, most injury analyses have focused on one-dimensional injury variables, such as the AIS (Abbreviated Injury Scale) or the IIS (Injury Impairment Scale), at a time in relation to various traffic accident factors. However, these studies cannot reflect the various injury phenomena that appear simultaneously. In this paper, we apply quantification method II to the NASS (National Automotive Sampling System) CDS (Crashworthiness Data System) to find the relationship between the categorical injury phenomena, such as the injury scale, injury position, and injury type, and the various traffic accident condition factors, such as speed, collision direction, vehicle type, and seat position. Our empirical analysis indicated the importance of safety devices, such as restraint equipment and airbags. In addition, we found that narrow impact, ejection, air bag deployment, and higher speed are associated with more severe than minor injury to the thigh, ankle, and leg in terms of dislocation, abrasion, or laceration. PMID:21094332

  20. Pilot Human Factors in Stall/Spin Accidents of Supersonic Fighter Aircraft

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.; Enevoldson, E. K.; Nguyen, L. T.

    1983-01-01

    A study has been made of pilot human factors related to stall/spin accidents of supersonic fighter aircraft. The military specifications for flight at high angles of attack are examined. Several pilot human factors problems related to stall/spin are discussed. These problems include (1) unsatisfactory nonvisual warning cues; (2) the inability of the pilot to quickly determine if the aircraft is spinning out of control, or to recognize the type of spin; (3) the inability of the pilot to decide on and implement the correct spin recovery technique; (4) the inability of the pilot to move, caused by high angular rotation; and (5) the tendency of pilots to wait too long in deciding to abandon the irrecoverable aircraft. Psycho-physiological phenomena influencing pilot's behavior in stall/spin situations include (1) channelization of sensory inputs, (2) limitations in precisely controlling several muscular inputs, (3) inaccurate judgment of elapsed time, and (4) disorientation of vestibulo-ocular inputs. Results are given of pilot responses to all these problems in the F14A, F16/AB, and F/A-18A aircraft. The use of departure spin resistance and automatic spin prevention systems incorporated on recent supersonic fighters are discussed. These systems should help to improve the stall/spin accident record with some compromise in maneuverability.

  1. [Genetic effects of bystander factors from the blood sera of people irradiated as the result of the Chernobyl accident].

    PubMed

    Morozik, P M; Mosse, I B; Mel'nov, S B; Morozik, M S; Seymour, K B; Mothersill, C E

    2011-01-01

    The purpose of this work was the analysis of the effects of bystander factors from blood sera of people affected by the Chernobyl accident on human keratinocyte cell culture (HPV-G cells). A new method was developed for evaluation of the bystander factor presence in vivo in blood of the people irradiated by the Chernobyl accident. Affected population groups included liquidators of the Chernobyl accident and people living and working in areas of the Gomel region contaminated by radionuclides. The analysis has shown that bystander factors persist in Chernobyl liquidator blood samples for more than 20 years since irradiation. The data suggest that blood sera contain bystander factors, which are able to induce micronuclei and decrease the metabolic activity of HPV-G cells.

  2. NASA-ONERA Collaboration on Human Factors in Aviation Accidents and Incidents

    NASA Technical Reports Server (NTRS)

    Srivastava, Ashok N.; Fabiani, Patrick

    2012-01-01

    This is the first annual report jointly prepared by NASA and ONERA on the work performed under the agreement to collaborate on a study of the human factors entailed in aviation accidents and incidents, particularly focused on the consequences of decreases in human performance associated with fatigue. The objective of this agreement is to generate reliable, automated procedures that improve understanding of the levels and characteristics of flight-crew fatigue factors whose confluence will likely result in unacceptable crew performance. This study entails the analyses of numerical and textual data collected during operational flights. NASA and ONERA are collaborating on the development and assessment of automated capabilities for extracting operationally significant information from very large, diverse (textual and numerical) databases; much larger than can be handled practically by human experts.

  3. An application of GIS and Bayesian network in studying spatial-causal relations between enterprises and environmental factors

    NASA Astrophysics Data System (ADS)

    Shen, Tiyan; Li, Xi; Li, Maiqing

    2009-10-01

    The paper intends to employ Geographic Information System (GIS) and Bayesian Network to discover the spatial causality between enterprises and environmental factors in Beijing Metropolis. The census data of Beijing was spatialized by means of GIS in the beginning, and then the training data was made using density mapping technique. Base on the training data, the structure of a Bayesian Network was learnt with the help of Maximum Weight Spanning Tree. Eight direct relations were discussed in the end, of which, the most exciting discovery, "Enterprise-Run Society", as the symbol of the former planned economy, was emphasized in the spatial relations between heavy industry and schools. Though the final result is not so creative in economic perspective, it is of significance in technique view due to all discoveries were drawn from data, therefore leading to the realization of the importance of GIS and data mining to economic geography research.

  4. 49 CFR 225.12 - Rail Equipment Accident/Incident Reports alleging employee human factor as cause; Employee Human...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Rail Equipment Accident/Incident Reports alleging employee human factor as cause; Employee Human Factor Attachment; notice to employee; employee supplement. 225.12 Section 225.12 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT...

  5. Clastogenic factors in the plasma of Chernobyl accident recovery workers: Anticlastogenic effect of Ginkgo biloba extract

    SciTech Connect

    Emerit, I.; Levy, A.; Cernjavski, L.

    1995-11-01

    Clastogenic factors are found in the plasma of persons irradiated accidentally or therapeutically. They persisted in the plasma of A-bomb survivors over 30 years. Clastogenic factors were found in 33 or 47 Chernobyl accident recovery workers (often referred to as liquidators) in a previous study. In the present study, we show that there is a positive correlation between clastogenic activity and dose and that these biomarkers of oxidative stress can be influenced successfully by appropriate antioxidant treatment. With the authorization of the Armenian Ministry of Health, 30 workers were treated with antioxidants from Ginkgo biloba leaves. The extract EGb 761 containing flavonoids and terpenoids was given at a daily dose of 3 x 40 mg (Tanakan, IPSEN, France) during 2 months. The clastogenic activity of the plasma was reduced to control levels on the first day after the end of the treatment. A 1-year follow-up showed that the benefit of the treatment persisted for at least 7 months. One-third of the workers again had clastogenic factors after 1 year, demonstrating that the process which produced clastogenic factors continued. However, the observation that antioxidants do not have to be given continuously is encouraging for intervention trials on a large-scale basis. These appear justified, since clastogenic factors are thought to be risk factors for the development of late effects of irradiation. 43 refs., 6 tabs.

  6. Learning from the Piper Alpha accident: A postmortem analysis of technical and organizational factors

    SciTech Connect

    Pate-Cornell, M.E. )

    1993-04-01

    The accident that occurred on board the offshore platform Piper Alpha in July 1988 killed 167 people and cost billions of dollars in property damage. It was caused by a massive fire, which was not the result of an unpredictable act of God' but of an accumulation of errors and questionable decisions. Most of them were rooted in the organization, its structure, procedures, and culture. This paper analyzes the accident scenario using the risk analysis framework, determines which human decision and actions influenced the occurrence of the basic events, and then identifies the organizational roots of these decisions and actions. These organizational factors are generalizable to other industries and engineering systems. They include flaws in the design guidelines and design practices (e.g., tight physical couplings or insufficient redundancies), misguided priorities in the management of the tradeoff between productivity and safety, mistakes in the management of the personnel on board, and errors of judgement in the process by which financial pressures are applied on the production sector (i.e., the oil companies' definition of profit centers) resulting in deficiencies in inspection and maintenance operations. This analytical approach allows identification of risk management measures that go beyond the purely technical (e.g., add redundancies to a safety system) and also include improvements of management practices. 18 refs., 4 figs.

  7. Residence place as a risk factor in different types of fatal car accidents.

    PubMed

    Leveau, Carlos M; Vacchino, Marta N

    2015-01-01

    The association between place of residence, population density, relief and type of event (collision or non-collision of the vehicle) has not been evaluated in developing countries. The main objective of this study is to determine the differential factors associated with the occurrence of deaths of collision and non-collision automobile users in Patagonia, Argentina. A multiple logistic regression analysis was performed using as the dependent variable death by car accident (collision or non-collision of the vehicle) and sex, age, place of residence of the victim, relief and population density as the independent variables. Collision fatalities were related to areas of high population density, while non-collision fatalities were related to areas of low population density, mountainous landscape and place of residence of the victims outside the Patagonian region. The results obtained in this study indicate the need to develop differential primary prevention policies by place of residence of car occupants, focusing on Patagonia non-resident drivers and by emphasising non-collision accidents.

  8. Factors associated with nurses' intention to leave their jobs after the Fukushima Daiichi Nuclear Power plant accident.

    PubMed

    Sato, Yoshinobu; Hayashida, Naomi; Orita, Makiko; Urata, Hideko; Shinkawa, Tetsuko; Fukushima, Yoshiko; Nakashima, Yumiko; Kudo, Takashi; Yamashita, Shunichi; Takamura, Noboru

    2015-01-01

    We conducted a survey among nurses who were working at the Fukushima Medical University Hospital at the time of the Fukushima Daiichi Nuclear Power Plant accident to clarify the factors associated with their intention to leave their jobs during the radiation emergency. We asked 345 nurses (17 men and 328 women) about their intention to leave their jobs after the accident. We also asked about relevant factors including the participants' demographic factors, living situation, working status, and knowledge of radiation health effects. We found that living with preschoolers (OR = 1.87, 95%CI: 1.02-3.44, p = 0.042), anxiety about life in Fukushima City after the accident (OR = 5.55, 95%CI: 1.18-26.13, p = 0.030), consideration of evacuation from Fukushima after the accident (OR = 2.42, 95%CI: 1.45-4.06, p = 0.001), consideration of the possible radiation health effects in children (OR = 1.90, 95%CI: 1.02-3.44, p = 0.042), and anxiety about relationships with colleagues in the hospital after the accident (OR = 3.23, p = 0.001) were independently associated with the nurses' intention to leave their jobs after the accident. On the other hand, the percentage of nurses with knowledge on radiation health effects was relatively low among those who had the intention to leave the job and among those who did not have the intention to leave the job after the accident, with no significant differences between the two groups. Our results suggest the need for an education program for nurses regarding radiation health effects.

  9. Factors Associated with Nurses’ Intention to Leave Their Jobs after the Fukushima Daiichi Nuclear Power Plant Accident

    PubMed Central

    Sato, Yoshinobu; Hayashida, Naomi; Orita, Makiko; Urata, Hideko; Shinkawa, Tetsuko; Fukushima, Yoshiko; Nakashima, Yumiko; Kudo, Takashi; Yamashita, Shunichi; Takamura, Noboru

    2015-01-01

    We conducted a survey among nurses who were working at the Fukushima Medical University Hospital at the time of the Fukushima Daiichi Nuclear Power Plant accident to clarify the factors associated with their intention to leave their jobs during the radiation emergency. We asked 345 nurses (17 men and 328 women) about their intention to leave their jobs after the accident. We also asked about relevant factors including the participants’ demographic factors, living situation, working status, and knowledge of radiation health effects. We found that living with preschoolers (OR = 1.87, 95%CI: 1.02–3.44, p = 0.042), anxiety about life in Fukushima City after the accident (OR = 5.55, 95%CI: 1.18–26.13, p = 0.030), consideration of evacuation from Fukushima after the accident (OR = 2.42, 95%CI: 1.45–4.06, p = 0.001), consideration of the possible radiation health effects in children (OR = 1.90, 95%CI: 1.02–3.44, p = 0.042), and anxiety about relationships with colleagues in the hospital after the accident (OR = 3.23, p = 0.001) were independently associated with the nurses’ intention to leave their jobs after the accident. On the other hand, the percentage of nurses with knowledge on radiation health effects was relatively low among those who had the intention to leave the job and among those who did not have the intention to leave the job after the accident, with no significant differences between the two groups. Our results suggest the need for an education program for nurses regarding radiation health effects. PMID:25816345

  10. Factors associated with nurses' intention to leave their jobs after the Fukushima Daiichi Nuclear Power plant accident.

    PubMed

    Sato, Yoshinobu; Hayashida, Naomi; Orita, Makiko; Urata, Hideko; Shinkawa, Tetsuko; Fukushima, Yoshiko; Nakashima, Yumiko; Kudo, Takashi; Yamashita, Shunichi; Takamura, Noboru

    2015-01-01

    We conducted a survey among nurses who were working at the Fukushima Medical University Hospital at the time of the Fukushima Daiichi Nuclear Power Plant accident to clarify the factors associated with their intention to leave their jobs during the radiation emergency. We asked 345 nurses (17 men and 328 women) about their intention to leave their jobs after the accident. We also asked about relevant factors including the participants' demographic factors, living situation, working status, and knowledge of radiation health effects. We found that living with preschoolers (OR = 1.87, 95%CI: 1.02-3.44, p = 0.042), anxiety about life in Fukushima City after the accident (OR = 5.55, 95%CI: 1.18-26.13, p = 0.030), consideration of evacuation from Fukushima after the accident (OR = 2.42, 95%CI: 1.45-4.06, p = 0.001), consideration of the possible radiation health effects in children (OR = 1.90, 95%CI: 1.02-3.44, p = 0.042), and anxiety about relationships with colleagues in the hospital after the accident (OR = 3.23, p = 0.001) were independently associated with the nurses' intention to leave their jobs after the accident. On the other hand, the percentage of nurses with knowledge on radiation health effects was relatively low among those who had the intention to leave the job and among those who did not have the intention to leave the job after the accident, with no significant differences between the two groups. Our results suggest the need for an education program for nurses regarding radiation health effects. PMID:25816345

  11. Expert explanations of honeybee losses in areas of extensive agriculture in France: Gaucho® compared with other supposed causal factors

    NASA Astrophysics Data System (ADS)

    Maxim, L.; van der Sluijs, J. P.

    2010-01-01

    Debates on causality are at the core of controversies as regards environmental changes. The present paper presents a new method for analyzing controversies on causality in a context of social debate and the results of its empirical testing. The case study used is the controversy as regards the role played by the insecticide Gaucho®, compared with other supposed causal factors, in the substantial honeybee (Apis mellifera L.) losses reported to have occurred in France between 1994 and 2004. The method makes use of expert elicitation of the perceived strength of evidence regarding each of Bradford Hill's causality criteria, as regards the link between each of eight possible causal factors identified in attempts to explain each of five signs observed in honeybee colonies. These judgments are elicited from stakeholders and experts involved in the debate, i.e., representatives of Bayer Cropscience, of the Ministry of Agriculture, of the French Food Safety Authority, of beekeepers and of public scientists. We show that the intense controversy observed in confused and passionate public discourses is much less salient when the various arguments are structured using causation criteria. The contradictions between the different expert views have a triple origin: (1) the lack of shared definition and quantification of the signs observed in colonies; (2) the lack of specialist knowledge on honeybees; and (3) the strategic discursive practices associated with the lack of trust between experts representing stakeholders having diverging stakes in the case.

  12. Approaches for Strengthening Causal Inference Regarding Prenatal Risk Factors for Childhood Behavioural and Psychiatric Disorders

    ERIC Educational Resources Information Center

    Lewis, Sarah J.; Relton, Caroline; Zammit, Stanley; Smith, George Davey

    2013-01-01

    Background: The risk of childhood behavioural and psychiatric diseases could be substantially reduced if modifiable risk factors for these disorders were identified. The critical period for many of these exposures is likely to be in utero as this is the time when brain development is most rapid. However, due to confounding and other limitations of…

  13. Chronic Kidney Disease Itself Is a Causal Risk Factor for Stroke beyond Traditional Cardiovascular Risk Factors: A Nationwide Cohort Study in Taiwan

    PubMed Central

    Chen, Yi-Chun; Su, Yu-Chieh; Lee, Ching-Chih; Huang, Yung-Sung; Hwang, Shang-Jyh

    2012-01-01

    Background Cardiovascular disease (CVD) is a leading cause of mortality and morbidity in patients with chronic kidney disease (CKD). In Taiwan, CVD is dominated by strokes but there is no robust evidence for a causal relationship between CKD and stroke. This study aimed to explore such causal association. Methods We conducted a nationwide retrospective cohort study based on the Taiwan National Health Insurance Research Database from 2004 to 2007. Each patient identified was individually tracked for a full three years from the index admission to identify those in whom any type of stroke developed. The study cohort consisted of patients hospitalized with a principal diagnosis of CKD and no traditional cardiovascular risk factors at baseline (n = 1393) and an age-matched control cohort of patients hospitalized for appendectomies (n = 1393, a surrogate for the general population). Cox proportional hazard regression and propensity score model were used to compare the three-year stroke-free survival rate of the two cohorts after adjustment for possible confounding factors. Results There were 256 stroke patients, 156 (11.2%) in the study cohort and 100 (7.2%) in the control cohort. After adjusting for covariates, patients with primary CKD had a 1.94-fold greater risk for stroke (95% CI, 1.45–2.60; p<0.001) based on Cox regression and a 1.68-fold greater risk for stroke (95% CI, 1.25–2.25; p = 0.001) based on propensity score. This was still the case for two cohorts younger than 75 years old and without traditional cardiovascular risk factors. Conclusions This study of Taiwanese patients indicates that CKD itself is a causal risk factor for stroke beyond the traditional cardiovascular risk factors. Primary CKD patients have higher risk for stroke than the general population and all CKD patients, irrespective of the presence or severity of traditional cardiovascular risk factors, should be made aware of the stroke risk and monitored for stroke prevention

  14. The causality field (extrinsic and intrinsic factors) in industrial subacute low back pain patients.

    PubMed

    Ohlund, C; Lindström, I; Eek, C; Areskoug, B; Nachemson, A

    1996-04-01

    In a prospective, randomized study, primarily designed to test the efficacy of activation on consecutive blue-collar workers sick-listed for 6 weeks due to subacute low back pain, 25% of the workers were excluded for medical reasons. In the intervention study (n = 103), only a minority of cases (6%) had 'true' subacute complaints, i.e. no prior history of low back pain. Subjective reports on general well-being, health status and work-related ergonomic factors were significantly lower or worse in patients than in reference samples. The randomized intervention study could establish a significant effect of graded activation on work return, but the effect seemed to be restricted to patients moderately disabled, i.e. one-third of the subacute low back pain patients included. A predictive four-factor model on work return increased the possibility of identifing nonresponders (chronic low back pain) more than threefold with a specificity (91%) and sensitivity (74%) comparable to that of clinical disc herniation. The history of a prolonged disablement process, cognitive factors, pain behavior and mentally straining ergonomic factors seemed to be of importance. Psychological reactions, or 'barriers to recovery', were slightly different in treatment and control groups but the type of intervention did not significantly alter the predictive model, suggesting that subsets of the study sample may benefit from other optional functional approaches. Descriptive characteristics of the study sample emphasized that subacute low back pain patients cannot be conceptualized as a homogeneous group. Four sub-groups could be identified: (a) specific medical disorders; (b) spontaneous recovery group; (c) moderately disabled back pain patients; and (d) nonresponders. The results support proposals that treatment should be tailored according to individual needs and that better case management should have priority for those belonging to the nonresponder group.

  15. Epidemiological causality.

    PubMed

    Morabia, Alfredo

    2005-01-01

    Epidemiological methods, which combine population thinking and group comparisons, can primarily identify causes of disease in populations. There is therefore a tension between our intuitive notion of a cause, which we want to be deterministic and invariant at the individual level, and the epidemiological notion of causes, which are invariant only at the population level. Epidemiologists have given heretofore a pragmatic solution to this tension. Causal inference in epidemiology consists in checking the logical coherence of a causality statement and determining whether what has been found grossly contradicts what we think we already know: how strong is the association? Is there a dose-response relationship? Does the cause precede the effect? Is the effect biologically plausible? Etc. This approach to causal inference can be traced back to the English philosophers David Hume and John Stuart Mill. On the other hand, the mode of establishing causality, devised by Jakob Henle and Robert Koch, which has been fruitful in bacteriology, requires that in every instance the effect invariably follows the cause (e.g., inoculation of Koch bacillus and tuberculosis). This is incompatible with epidemiological causality which has to deal with probabilistic effects (e.g., smoking and lung cancer), and is therefore invariant only for the population.

  16. Analysis of causal factors of fire regimes in Sub-Saharan Africa

    NASA Astrophysics Data System (ADS)

    Palumbo, I.; Lehsten, V.; Balzter, H.

    2009-04-01

    Wildfires are a wide spread global phenomenon. Their activity peaks in the tropical savannas, especially in the African continent, where fires are a key component of ecosystem dynamics. Fires affect the ecological balance between trees and grasses in savannas with concomitant effects on biodiversity, soil fertility and biogeochemical cycles. Large amounts of trace greenhouse gases and aerosols from wildfires are emitted each year in Africa, but the underlying dynamics of such wildfires and what drives them remain poorly understood. In general terms, the magnitude and the inter-annual variability of fire activity depend on fire frequency and its spatial distribution, also referred to as fire regimes. These are, in turn, determined by the environmental conditions at the time of burning, ignition sources, fuel type, fuel availability, and its moisture content. This study analysed the driving factors of fire regimes at continental level for a period of 5 years (2002-2007). We considered the following variables: climate (rainfall, temperature, humidity), population density, land cover and the burned areas derived from the MODIS MCD45A1 product at 500m resolution. GIS and multi-variate regression techniques were used to analyse the data. Understanding fire driving factors is fundamentally important for developing process-based simulation models of fire occurrence under future climate and environmental change scenarios. This is particularly relevant if we consider that the IPCC 4th Assessment report indicates that a change in the rainfall patterns has been observed in the last 40 years over most of Africa with a decrease of precipitation around 20-40% in West Africa and more intense and widespread droughts in Southern Africa. The simultaneous increase of temperatures can potentially lead to higher fire occurrence and modify the current fire regimes. This work contributes to climate change research with new insights and understanding about how fires are controlled by

  17. Derivation of Accident-Specific Material-at-Risk Equivalency Factors

    SciTech Connect

    Jason P. Andrus; Dr. Chad L. Pope

    2012-05-01

    A novel method for calculating material at risk (MAR) dose equivalency developed at the Idaho National Laboratory (INL) now allows for increased utilization of dose equivalency for facility MAR control. This method involves near-real time accounting for the use of accident and material specific release and transport. It utilizes all information from the committed effective dose equation and the five factor source term equation to derive dose equivalency factors which can be used to establish an overall facility or process MAR limit. The equivalency factors allow different nuclide spectrums to be compared for their respective dose consequences by relating them to a specific quantity of an identified reference nuclide. The ability to compare spectrums to a reference limit ensures that MAR limits are in fact bounding instead of attempting to establish a representative or bounding spectrum which may lead to unintended or unanalyzed configurations. This methodology is then coupled with a near real time material tracking system which allows for accurate and timely material composition information and corresponding MAR equivalency values. The development of this approach was driven by the complex nature of processing operations in some INL facilities. This type of approach is ideally suited for facilities and processes where the composition of the MAR and possible release mechanisms change frequently but in well defined fashions and in a batch-type nature.

  18. First Annual Report: NASA-ONERA Collaboration on Human Factors in Aviation Accidents and Incidents

    NASA Technical Reports Server (NTRS)

    Srivastava, Ashok; Fabiani, Patrick

    2012-01-01

    This is the first annual report jointly prepared by NASA and ONERA on the work performed under the agreement to collaborate on a study of the human factors entailed in aviation accidents and incidents particularly focused on consequences of decreases in human performance associated with fatigue. The objective of this Agreement is to generate reliable, automated procedures that improve understanding of the levels and characteristics of flight-crew fatigue factors whose confluence will likely result in unacceptable crew performance. This study entails the analyses of numerical and textual data collected during operational flights. NASA and ONERA are collaborating on the development and assessment of automated capabilities for extracting operationally significant information from very large, diverse (textual and numerical) databases much larger than can be handled practically by human experts. This report presents the approach that is currently expected to be used in processing and analyzing the data for identifying decrements in aircraft performance and examining their relationships to decrements in crewmember performance due to fatigue. The decisions on the approach were based on samples of both the numerical and textual data that will be collected during the four studies planned under the Human Factors Monitoring Program (HFMP). Results of preliminary analyses of these sample data are presented in this report.

  19. Cellular phones and traffic accidents: an epidemiological approach.

    PubMed

    Violanti, J M; Marshall, J R

    1996-03-01

    Using epidemiological case-control design and logistic regression techniques, this study examined the association of cellular phone use in motor vehicles and traffic accident risk. The amount of time per month spent talking on a cellular phone and 18 other driver inattention factors were examined. Data were obtained from: (1) a case group of 100 randomly selected drivers involved in accidents within the past 2 years, and (2) a control group of 100 randomly selected licensed drivers not involved in accidents within the past 10 years. Groups were matched on geographic residence. Approximately 13% (N = 7) of the accident and 9% (N = 7) of the non-accident group reported use of cellular phones while driving. Data was obtained from Department of Motor Vehicles accident reports and survey information from study subjects. We hypothesized that increased use of cellular phones while driving was associated with increased odds of a traffic accident. Results indicated that talking more than 50 minutes per month on cellular phones in a vehicle was associated with a 5.59-fold increased risk in a traffic accident. The combined use of cellular phones and motor and cognitive activities while driving were also associated with increased traffic accident risk. Readers should be cautioned that this study: (1) consists of a small sample, (2) reveals statistical associations and not causal relationships, and (3) does not conclude that talking on cellular phones while driving is inherently dangerous.

  20. Oxidative stress as a potential causal factor for autoimmune hemolytic anemia and systemic lupus erythematosus

    PubMed Central

    Fujii, Junichi; Kurahashi, Toshihiro; Konno, Tasuku; Homma, Takujiro; Iuchi, Yoshihito

    2015-01-01

    The kidneys and the blood system mutually exert influence in maintaining homeostasis in the body. Because the kidneys control erythropoiesis by producing erythropoietin and by supporting hematopoiesis, anemia is associated with kidney diseases. Anemia is the most prevalent genetic disorder, and it is caused by a deficiency of glucose 6-phosphate dehydrogenase (G6PD), for which sulfhydryl oxidation due to an insufficient supply of NADPH is a likely direct cause. Elevated reactive oxygen species (ROS) result in the sulfhydryl oxidation and hence are another potential cause for anemia. ROS are elevated in red blood cells (RBCs) under superoxide dismutase (SOD1) deficiency in C57BL/6 mice. SOD1 deficient mice exhibit characteristics similar to autoimmune hemolytic anemia (AIHA) and systemic lupus erythematosus (SLE) at the gerontic stage. An examination of AIHA-prone New Zealand Black (NZB) mice, which have normal SOD1 and G6PD genes, indicated that ROS levels in RBCs are originally high and further elevated during aging. Transgenic overexpression of human SOD1 in erythroid cells effectively suppresses ROS elevation and ameliorates AIHA symptoms such as elevated anti-RBC antibodies and premature death in NZB mice. These results support the hypothesis that names oxidative stress as a risk factor for AIHA and other autoimmune diseases such as SLE. Herein we discuss the association between oxidative stress and SLE pathogenesis based mainly on the genetic and phenotypic characteristics of NZB and New Zealand white mice and provide insight into the mechanism of SLE pathogenesis. PMID:25949934

  1. Distribution of Causes in Selected US Aviation Accident Reports Between 1996 and 2003

    NASA Technical Reports Server (NTRS)

    Holloway, C. M.; Johnson, C. W.

    2004-01-01

    This paper describes the results of an independent analysis of the probable and contributory causes of selected aviation accidents in the United States between 1996 and 2003. The purpose of the study was to assess the comparative frequency of a variety of causal factors in the reporting of these adverse events. Although our results show that more of these high consequence accidents were attributed to human error than to any other single factor, a large number of reports also mentioned wider systemic issues, including the managerial and regulatory context of aviation operations. These wider issues are more likely to appear as contributory rather than primary causes in this set of accident reports.

  2. [Environmental and indoor air exposure to asbestos fiber dust as a risk and causal factor of diffuse malignant pleural mesothelioma].

    PubMed

    Schneider, J; Rödelsperger, K; Pohlabeln, H; Woitowitz, H J

    1996-11-01

    In an interdisciplinary, multicentre case control study of the causal factors of the diffuse malignant mesothelioma (DMM) standardised histories where taken from n = 324 Patients suffering from DMM, n = 315 hospital control patients (KK) and n = 182 population controls (PK). For 66 DMM, 149 KK and 107 PK a risk from asbestos fibre dust at the workplace was not detectable. For latter persons indoor and outdoor asbestos exposure outside of the workplace were investigated. The following factors were examined: neighbourhood exposure from companies using asbestos, living in big cities and nearby main traffic roads, building materials containing asbestos, electric storage heaters and household contacts. For using electric storage heaters a statistically significant increased odds ratio (OR) was observed for DMM as well in comparison with KK (OR = 2.42; 95%-CI: 1.01-5.72) and in comparison for PK (OR = 2.91; 95%-CI: 1.08-7.80). Only outside of Hamburg an increased OR compared to KK was observed for people living in the neighbourhood of asbestos factories (OR = 16.3; 95%-CI: 1.35-196.8) and also, but only in Hamburg, compared to PK living nearby main traffic roads. There is only a trend for a mesothelioma-risk for household-contacts based on a few cases. In one DMM-patient without an occupational asbestos exposure the lung dust fibre analysis yielded 2.912 FB and 1.459 x 10(3) crocydolithe fibres per gram dried lung tissue. As a child he lived in the immediate vicinity of the blue asbestos mine in Wittenoom, Australia. Therefore in special cases a para-occupational asbestos or a neighbourhood asbestos exposure can be demonstrated as a risk factor of diffuse malignant mesothelioma.

  3. Bayes classifiers for imbalanced traffic accidents datasets.

    PubMed

    Mujalli, Randa Oqab; López, Griselda; Garach, Laura

    2016-03-01

    Traffic accidents data sets are usually imbalanced, where the number of instances classified under the killed or severe injuries class (minority) is much lower than those classified under the slight injuries class (majority). This, however, supposes a challenging problem for classification algorithms and may cause obtaining a model that well cover the slight injuries instances whereas the killed or severe injuries instances are misclassified frequently. Based on traffic accidents data collected on urban and suburban roads in Jordan for three years (2009-2011); three different data balancing techniques were used: under-sampling which removes some instances of the majority class, oversampling which creates new instances of the minority class and a mix technique that combines both. In addition, different Bayes classifiers were compared for the different imbalanced and balanced data sets: Averaged One-Dependence Estimators, Weightily Average One-Dependence Estimators, and Bayesian networks in order to identify factors that affect the severity of an accident. The results indicated that using the balanced data sets, especially those created using oversampling techniques, with Bayesian networks improved classifying a traffic accident according to its severity and reduced the misclassification of killed and severe injuries instances. On the other hand, the following variables were found to contribute to the occurrence of a killed causality or a severe injury in a traffic accident: number of vehicles involved, accident pattern, number of directions, accident type, lighting, surface condition, and speed limit. This work, to the knowledge of the authors, is the first that aims at analyzing historical data records for traffic accidents occurring in Jordan and the first to apply balancing techniques to analyze injury severity of traffic accidents.

  4. [Determinant factors and conduct in post-accident with biological material among pre-hospital professionals].

    PubMed

    Paiva, Maria Henriqueta Rocha Siqueira; Oliveira, Adriana Cristina

    2011-01-01

    This transversal study was carried out with a multiprofessional team in the pre-hospital care in Minas Gerais, Brazil. It aimed to estimate the incidence of occupational accidents by exposure to biological material and post-accidents conductsta. Descriptive analysis and logistic regression were used. Incidence of accidents was 19.8%: 39,1% perforating-cutting materials and 56.5% body fluids. Doctors (33.3%) and drivers (24.0%) were most involved. Inadequate subsequent measures were highly prevalent: no medical assessment (69.6%), no work accident communication issued (91.3%), no measures (52.2%) and no serological follow-up (52.2%). Variables associated with accidents were: age >31 years old (OR = 3,02; IC95%: 1,25 - 7,33; p = 0,014) and working in basic support units (OR = 5,36; IC95%: 1,51 19,08; p = 0,010). The implementation of post-accidents protocols is suggested in order to reduce accidents and under-notification, and increase post-accident follow-up.

  5. Driving habits and risk factors for traffic accidents among sleep apnea patients--a European multi-centre cohort study.

    PubMed

    Karimi, Mahssa; Hedner, Jan; Lombardi, Carolina; Mcnicholas, Walter T; Penzel, Thomas; Riha, Renata L; Rodenstein, Daniel; Grote, Ludger

    2014-12-01

    Obstructive sleep apnea is associated with increased motor vehicle accident risk, and improved detection of patients at risk is of importance. The present study addresses potential risk factors in the European Sleep Apnea Database and includes patients with suspected obstructive sleep apnea [n = 8476, age 51.5 (12.5) years, body mass index 31.0 (6.6) kg m(-2) , 82.4% driver's licence holders]. Driving distance (km year(-1) ), driver's licence type, sleep apnea severity, sleepiness and comorbidities were assessed. Previously validated risk factors for accident history: Epworth Sleepiness Scale ≥16; habitual sleep time ≤5 h; use of hypnotics; and driving ≥15 000 km year(-1) were analysed across European regions. At least one risk factor was identified in male and female drivers, 68.75 and 51.3%, respectively. The occurrence of the risk factors was similar across Europe, with only a lower rate in the eastern region (P = 0.001). The mean number of risk factors increased across classes of sleep apnea severity. Frequent driving was prevalent [14.0 (interquartile range 8.0-20.0) × 10(3)  km year(-1) ] and 32.7% of drivers had severe obstructive sleep apnea [apnea-hypopnea index 50.3 (38.8-66.0) n h(-1) ]. Obesity, shorter sleep time and younger age were associated with increased traffic exposure (P ≤ 0.03). In conclusion, the risk factors associated with accident history were common among European patients with suspected obstructive sleep apnea, but varied between geographical regions. There was a weak covariation between occurrence of risk factors and clinically determined apnea severity but frequent driving, a strong risk factor for accidents, was over-represented. Systematic evaluation of accident-related risk factors is important to detect sleep apnea patients at risk for motor vehicle accidents.

  6. Risk Factors for Accident Death in the U.S. Army, 2004–2009

    PubMed Central

    Lewandowski-Romps, Lisa; Peterson, Christopher; Berglund, Patricia A.; Collins, Stacey; Cox, Kenneth; Hauret, Keith; Jones, Bruce; Kessler, Ronald C.; Mitchell, Colter; Park, Nansook; Schoenbaum, Michael; Stein, Murray B.; Ursano, Robert J.; Heeringa, Steven G.

    2014-01-01

    Background Accidents are one of the leading causes of death among U.S. active duty Army soldiers. Evidence-based approaches to injury prevention could be strengthened by adding person-level characteristics (e.g., demographics) to risk models tested on diverse soldier samples studied over time. Purpose To identify person-level risk indicators of accident deaths in Regular Army soldiers during a time frame of intense military operations, and to discriminate risk of not-line-of-duty (NLOD) from line-of-duty (LOD) accident deaths. Methods Administrative data acquired from multiple Army/Department of Defense sources for active duty Army soldiers during 2004–2009 were analyzed in 2013. Logistic regression modeling was used to identify person-level sociodemographic, service-related, occupational, and mental health predictors of accident deaths. Results Delayed rank progression or demotion and being male, unmarried, in a combat arms specialty, and of low rank/service length increased odds of accident death for enlisted soldiers. Unique to officers was high risk associated with aviation specialties. Accident death risk decreased over time for currently deployed, enlisted soldiers while increasing for those never deployed. Mental health diagnosis was associated with risk only for previous and never-deployed, enlisted soldiers. Models did not discriminate NLOD from LOD accident deaths. Conclusions Adding more refined person-level and situational risk indicators to current models could enhance understanding of accident death risk specific to soldier rank and deployment status. Stable predictors could help identify high risk of accident deaths in future cohorts of Regular Army soldiers. PMID:25441238

  7. Causal Inference and Developmental Psychology

    ERIC Educational Resources Information Center

    Foster, E. Michael

    2010-01-01

    Causal inference is of central importance to developmental psychology. Many key questions in the field revolve around improving the lives of children and their families. These include identifying risk factors that if manipulated in some way would foster child development. Such a task inherently involves causal inference: One wants to know whether…

  8. Long-term variations and causal factors in nitrogen and phosphorus transport in the Yellow River, China

    NASA Astrophysics Data System (ADS)

    Tao, Yu; Wei, Meng; Ongley, Edwin; Li, Zicheng; Jingsheng, Chen

    2010-02-01

    This paper is to examine the water quality of the Yellow River basin on the basis of collated data of nitrogen (40 years) and phosphorus (20 years), and also of the relevant chemical fertilizer application, population, and industrial wastewater, etc. Relationship among these elements was discussed in order to explore their causal links, in relation to the temporal variation of nitrogen and phosphorus transportation. Results indicate that the transported nitrogen load in the lower Yellow River has had an increasing trend during the past 40 years but declined considerably in the later 1990s due to the reduction in flow discharge that led to desiccation of the lower reaches of the Yellow River. Whereas, nitrogen contribution to the estuary from Huayuankou to Lijin reach was minus due to the large amount of water diversion from the Yellow River for irrigation purpose. Phosphorus content fluctuated within a certain range without any tendency, but also decreased in the later 1990s due to the desiccation in the lower reaches. Our analysis indicates that nitrogen load in the Yellow River has been mainly impacted by population growth and nitrogen fertilizer application, but showed no statistically significant relationship with wastewater loads. In contrast, total phosphorus content in the Yellow River showed no relationship with population, fertilizer use and wastewater discharge in the basin, but presented significant correlation with suspended solids concentration of the Yellow River. Calculations indicate that the phosphorus content in suspended solids of the Yellow River was 0.54 g/kg, which is quite close to the background value of phosphorus in the soil of the Loess Plateau - the intensive soil erosion area in China, through which the Yellow River flows. Therefore, we conclude that phosphorus transportation in the Yellow River is dominantly controlled by soil erosion from the Loess Plateau. The results are significant for estuarine management in that nitrogen, a key

  9. Inroads into Equestrian Safety: Rider-Reported Factors Contributing to Horse-Related Accidents and Near Misses on Australian Roads

    PubMed Central

    Thompson, Kirrilly; Matthews, Chelsea

    2015-01-01

    Simple Summary Riding horses on roads can be dangerous, but little is known about accidents and near misses. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey, mostly attributed to speed. Whilst our findings confirmed factors identified overseas, we also identified issues around road rules, hand signals and road rage. This paper suggests strategies for improving the safety of horses, riders and other road users. Abstract Horse riding and horse-related interactions are inherently dangerous. When they occur on public roads, the risk profile of equestrian activities is complicated by interactions with other road users. Research has identified speed, proximity, visibility, conspicuity and mutual misunderstanding as factors contributing to accidents and near misses. However, little is known about their significance or incidence in Australia. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey. Whilst our findings confirm the factors identified overseas, we also identified issues around rider misunderstanding of road rules and driver misunderstanding of rider hand signals. Of particular concern, we also found reports of potentially dangerous rider-directed road rage. We identify several areas for potential safety intervention including (1) identifying equestrians as vulnerable road users and horses as sentient decision-making vehicles; (2) harmonising laws regarding passing horses; (3) mandating personal protective equipment; (4) improving road signage; (5) comprehensive data collection; (6) developing mutual understanding amongst road-users; (7) safer road design and alternative riding spaces; and (8) increasing investment

  10. Trends in state-level freight accident rates: An enhancement of risk factor development for RADTRAN

    SciTech Connect

    Saricks, C.; Kvitek, T.

    1991-01-01

    Under the Nuclear Waste Policy Act, the Department of Energy's Office of Civilian Radioactive Waste Management (OCRWM) is concerned with understanding and managing risk as it applies to the shipment of spent commercial nuclear reactor fuel. Understanding risk in relation to mode and geography may provide opportunities to minimize radiological and non-radiological risks of transportation. To enhance such an understanding, a set of state-or waterway-specific accident, fatality, and injury rates (expressed as rates per shipment kilometer) by transportation mode and highway administrative class was developed, using publicly-available data bases. Adjustments made to accommodate miscoded or incomplete information in accident data are described, as well as the procedures for estimating state-level flow data. Results indicate that the shipping conditions under which spent fuel is likely to be transported should be less subject to accidents than the average'' shipment within mode. 10 refs., 3 tabs.

  11. Partial least square method for modelling ergonomic risks factors on express bus accidents in the east coast of peninsular west Malaysia

    NASA Astrophysics Data System (ADS)

    Hashim, Yusof bin; Taha, Zahari bin

    2015-02-01

    Public, stake holders and authorities in Malaysian government show great concern towards high numbers of passenger's injuries and passengers fatalities in express bus accident. This paper studies the underlying factors involved in determining ergonomics risk factors towards human error as the reasons in express bus accidents in order to develop an integrated analytical framework. Reliable information about drivers towards bus accident should lead to the design of strategies intended to make the public feel safe in public transport services. In addition there is an analysis of ergonomics risk factors to determine highly ergonomic risk factors which led to accidents. The research was performed in east coast of peninsular Malaysia using variance-based structural equation modeling namely the Partial Least Squares (PLS) regression techniques. A questionnaire survey was carried out at random among 65 express bus drivers operating from the city of Kuantan in Pahang and among 49 express bus drivers operating from the city of Kuala Terengganu in Terengganu to all towns in the east coast of peninsular west Malaysia. The ergonomic risks factors questionnaire is based on demographic information, occupational information, organizational safety climate, ergonomic workplace, physiological factors, stress at workplace, physical fatigue and near miss accidents. The correlation and significant values between latent constructs (near miss accident) were analyzed using SEM SmartPLS, 3M. The finding shows that the correlated ergonomic risks factors (occupational information, t=2.04, stress at workplace, t = 2.81, physiological factor, t=2.08) are significant to physical fatigue and as the mediator to near miss accident at t = 2.14 at p<0.05and T-statistics, t>1.96. The results shows that the effects of physical fatigue due to ergonomic risks factors influence the human error as the reasons in express bus accidents.

  12. Partial least square method for modelling ergonomic risks factors on express bus accidents in the east coast of peninsular west Malaysia

    SciTech Connect

    Hashim, Yusof bin; Taha, Zahari bin

    2015-02-03

    Public, stake holders and authorities in Malaysian government show great concern towards high numbers of passenger’s injuries and passengers fatalities in express bus accident. This paper studies the underlying factors involved in determining ergonomics risk factors towards human error as the reasons in express bus accidents in order to develop an integrated analytical framework. Reliable information about drivers towards bus accident should lead to the design of strategies intended to make the public feel safe in public transport services. In addition there is an analysis of ergonomics risk factors to determine highly ergonomic risk factors which led to accidents. The research was performed in east coast of peninsular Malaysia using variance-based structural equation modeling namely the Partial Least Squares (PLS) regression techniques. A questionnaire survey was carried out at random among 65 express bus drivers operating from the city of Kuantan in Pahang and among 49 express bus drivers operating from the city of Kuala Terengganu in Terengganu to all towns in the east coast of peninsular west Malaysia. The ergonomic risks factors questionnaire is based on demographic information, occupational information, organizational safety climate, ergonomic workplace, physiological factors, stress at workplace, physical fatigue and near miss accidents. The correlation and significant values between latent constructs (near miss accident) were analyzed using SEM SmartPLS, 3M. The finding shows that the correlated ergonomic risks factors (occupational information, t=2.04, stress at workplace, t = 2.81, physiological factor, t=2.08) are significant to physical fatigue and as the mediator to near miss accident at t = 2.14 at p<0.05and T-statistics, t>1.96. The results shows that the effects of physical fatigue due to ergonomic risks factors influence the human error as the reasons in express bus accidents.

  13. On causality of extreme events

    PubMed Central

    2016-01-01

    Multiple metrics have been developed to detect causality relations between data describing the elements constituting complex systems, all of them considering their evolution through time. Here we propose a metric able to detect causality within static data sets, by analysing how extreme events in one element correspond to the appearance of extreme events in a second one. The metric is able to detect non-linear causalities; to analyse both cross-sectional and longitudinal data sets; and to discriminate between real causalities and correlations caused by confounding factors. We validate the metric through synthetic data, dynamical and chaotic systems, and data representing the human brain activity in a cognitive task. We further show how the proposed metric is able to outperform classical causality metrics, provided non-linear relationships are present and large enough data sets are available. PMID:27330866

  14. On causality of extreme events.

    PubMed

    Zanin, Massimiliano

    2016-01-01

    Multiple metrics have been developed to detect causality relations between data describing the elements constituting complex systems, all of them considering their evolution through time. Here we propose a metric able to detect causality within static data sets, by analysing how extreme events in one element correspond to the appearance of extreme events in a second one. The metric is able to detect non-linear causalities; to analyse both cross-sectional and longitudinal data sets; and to discriminate between real causalities and correlations caused by confounding factors. We validate the metric through synthetic data, dynamical and chaotic systems, and data representing the human brain activity in a cognitive task. We further show how the proposed metric is able to outperform classical causality metrics, provided non-linear relationships are present and large enough data sets are available.

  15. Assessing the Causality Factors in the Association between (Abdominal) Obesity and Physical Activity among the Newfoundland Population—A Mendelian Randomization Analysis

    PubMed Central

    Barning, Frank; Abarin, Taraneh

    2016-01-01

    A total of 1,263 adults from Newfoundland and Labrador were studied in the research. Body mass index (BMI) and percent trunk fat (PTF) were analyzed as biomarkers for obesity. The Mendelian randomization (MR) approach with two single-nucleotide polymorphisms in the fat-mass and obesity (FTO) gene as instruments was employed to assess the causal effect. In both genders, increasing physical activity significantly reduced BMI and PTF when adjusted for age and the FTO gene. The effect of physical activity was stronger on PTF than BMI. Direct observational analyses showed significant increase in BMI/PTF when physical activity decreased. A similar association in MR analyses was not significant. The association between physical activity and BMI/PTF could be due to reversed causality or common confounding factors. Our study provides insights into the causal contributions of obesity to physical activity in adults. Health intervention strategies to increase physical activity among adults should include some other plans such as improving diet for reducing obesity. PMID:27478388

  16. Causality in epidemiology.

    PubMed

    Kamangar, Farin

    2012-10-01

    This article provides an introduction to the meaning of causality in epidemiology and methods that epidemiologists use to distinguish causal associations from non-causal ones. Alternatives to causal association are discussed in detail. Hill's guidelines, set forth approximately 50 years ago, and more recent developments are reviewed. The role of religious and philosophic views in our understanding of causality is briefly discussed.

  17. New Technologies for Weather Accident Prevention

    NASA Technical Reports Server (NTRS)

    Stough, H. Paul, III; Watson, James F., Jr.; Daniels, Taumi S.; Martzaklis, Konstantinos S.; Jarrell, Michael A.; Bogue, Rodney K.

    2005-01-01

    Weather is a causal factor in thirty percent of all aviation accidents. Many of these accidents are due to a lack of weather situation awareness by pilots in flight. Improving the strategic and tactical weather information available and its presentation to pilots in flight can enhance weather situation awareness and enable avoidance of adverse conditions. This paper presents technologies for airborne detection, dissemination and display of weather information developed by the National Aeronautics and Space Administration (NASA) in partnership with the Federal Aviation Administration (FAA), National Oceanic and Atmospheric Administration (NOAA), industry and the research community. These technologies, currently in the initial stages of implementation by industry, will provide more precise and timely knowledge of the weather and enable pilots in flight to make decisions that result in safer and more efficient operations.

  18. Circular causality.

    PubMed

    Thomas, R

    2006-07-01

    The problem of disentangling complex dynamic systems is addressed, especially with a view to identifying those variables that take part in the essential qualitative behaviour of systems. The author presents a series of reflections about the methods of formalisation together with the principles that govern the global operation of systems. In particular, a section on circuits, nuclei, and circular causality and a rather detailed description of the analytic use of the generalised asynchronous logical description, together with a brief description of its synthetic use (OreverseO logic). Some basic rules are recalled, such as the fact that a positive circuit is a necessary condition of multistationarity. Also, the interest of considering as a model, rather than a well-defined set of differential equations, a variety of systems that differ from each other only by the values of constant terms is emphasised. All these systems have a common Jacobian matrix and for all of them phase space has exactly the same structure. It means that all can be partitioned in the same way as regards the signs of the eigenvalues and thus as regards the precise nature of any steady states that might be present. Which steady states are actually present, depends on the values of terms of order zero in the ordinary differential equations (ODEs), and it is easy to find for which values of these terms a given point in phase space is steady. Models can be synthesised first at the level of the circuits involved in the Jacobian matrix (that determines which types and numbers of steady states are consistent with the model), then only at the level of terms of order zero in the ODE's (that determines which of the steady states actually exist), hence the title 'Circular casuality'.

  19. Quantum causal modelling

    NASA Astrophysics Data System (ADS)

    Costa, Fabio; Shrapnel, Sally

    2016-06-01

    Causal modelling provides a powerful set of tools for identifying causal structure from observed correlations. It is well known that such techniques fail for quantum systems, unless one introduces ‘spooky’ hidden mechanisms. Whether one can produce a genuinely quantum framework in order to discover causal structure remains an open question. Here we introduce a new framework for quantum causal modelling that allows for the discovery of causal structure. We define quantum analogues for core features of classical causal modelling techniques, including the causal Markov condition and faithfulness. Based on the process matrix formalism, this framework naturally extends to generalised structures with indefinite causal order.

  20. Causal reasoning with forces

    PubMed Central

    Wolff, Phillip; Barbey, Aron K.

    2015-01-01

    Causal composition allows people to generate new causal relations by combining existing causal knowledge. We introduce a new computational model of such reasoning, the force theory, which holds that people compose causal relations by simulating the processes that join forces in the world, and compare this theory with the mental model theory (Khemlani et al., 2014) and the causal model theory (Sloman et al., 2009), which explain causal composition on the basis of mental models and structural equations, respectively. In one experiment, the force theory was uniquely able to account for people's ability to compose causal relationships from complex animations of real-world events. In three additional experiments, the force theory did as well as or better than the other two theories in explaining the causal compositions people generated from linguistically presented causal relations. Implications for causal learning and the hierarchical structure of causal knowledge are discussed. PMID:25653611

  1. Causally nonseparable processes admitting a causal model

    NASA Astrophysics Data System (ADS)

    Feix, Adrien; Araújo, Mateus; Brukner, Časlav

    2016-08-01

    A recent framework of quantum theory with no global causal order predicts the existence of ‘causally nonseparable’ processes. Some of these processes produce correlations incompatible with any causal order (they violate so-called ‘causal inequalities’ analogous to Bell inequalities) while others do not (they admit a ‘causal model’ analogous to a local model). Here we show for the first time that bipartite causally nonseparable processes with a causal model exist, and give evidence that they have no clear physical interpretation. We also provide an algorithm to generate processes of this kind and show that they have nonzero measure in the set of all processes. We demonstrate the existence of processes which stop violating causal inequalities but are still causally nonseparable when mixed with a certain amount of ‘white noise’. This is reminiscent of the behavior of Werner states in the context of entanglement and nonlocality. Finally, we provide numerical evidence for the existence of causally nonseparable processes which have a causal model even when extended with an entangled state shared among the parties.

  2. [Hyperinsulinemia as a factor preceding body mass increase in liquidators of the Chernobyl nuclear accident].

    PubMed

    Kovalenko, A N; Zueva, N A; Gerasimenko, T I; Efimov, A S

    2001-01-01

    Basal hyperinsulinemia has been recordable over several years in liquidators of the effects of Chernobyl Accident (ChAEL). There was no dependence of hyperinsulinemia on age, body mass or lenght of service of those persons having worked within the 30-km zone. The findings secured suggest to us that increase in the body mass index (BMI) in ChAEL is preceded by a rise in the blood level of insulin; there is no relatedness of the basal level of insulin in the blood to BMI.

  3. Time dependence of the {sup 137}Cs resuspension factor on the Romanian territory after the Chernobyl accident

    SciTech Connect

    Mihaila, B.; Cuculeanu, V.

    1994-08-01

    On the basis of the radioactivity levels in aerosol and atmospheric deposition samples due to the Chernobyl accident, the resuspension factor of {sup 137}Cs as a four-parameter function has been inferred. The standard procedure to derive the dependence of resuspension on time assumes that the initial deposit is instantaneous. A simple method assuming a constant deposition rate over a fixed period has been proposed. Also, based on existing experimental data, an attempt was made to consider a realistic time dependence of the deposition rate to cope with the particular case of the Chernobyl accident. The differences between the two models are outlined. The Chernobyl direct deposit has been assumed to be the deposit measured between 30 April and 30 June 1986. The calculated values of the resuspension factor are consistent with the IAEA`s recommended model and depend on the rainfall that occurred in June 1986 and the site-specific disturbance conditions during the first 100 d following 1 July 1986 and only on artificial disturbance by humans and vehicles after that. 16 refs., 5 figs., 3 tabs.

  4. Factors attributed to fatal occupational accidents in a period of 5 years preceding the Athens 2004 Olympic Games.

    PubMed

    Katsakiori, Panagiota; Manatakis, Emmanuel; Goutsos, Stavros; Athanassiou, George

    2008-01-01

    This study aimed to determine the factors attributed to occupational fatalities occurring in the region of East Attica, Greece, in all industry types over a 5-year period preceding the 2004 Olympic Games. Questionnaires, based on the attribution theory, were completed by labor inspectors and were analyzed with principal component analysis. The results showed that most accidents occurred in the construction industry due to large-scale civil works, which took place in East Attica prior to the 2004 Olympic Games. Poor work practices arising from lack of orientation and job training, performance pressure and workers' inexperience associated with knowledge- and skill-based errors were revealed by the questionnaire as the most common factors attributed to occupational fatalities. Our findings help to identify areas where prevention efforts should be directed to effectively manage safety in Greece. PMID:18954538

  5. How prescriptive norms influence causal inferences.

    PubMed

    Samland, Jana; Waldmann, Michael R

    2016-11-01

    Recent experimental findings suggest that prescriptive norms influence causal inferences. The cognitive mechanism underlying this finding is still under debate. We compare three competing theories: The culpable control model of blame argues that reasoners tend to exaggerate the causal influence of norm-violating agents, which should lead to relatively higher causal strength estimates for these agents. By contrast, the counterfactual reasoning account of causal selection assumes that norms do not alter the representation of the causal model, but rather later causal selection stages. According to this view, reasoners tend to preferentially consider counterfactual states of abnormal rather than normal factors, which leads to the choice of the abnormal factor in a causal selection task. A third view, the accountability hypothesis, claims that the effects of prescriptive norms are generated by the ambiguity of the causal test question. Asking whether an agent is a cause can be understood as a request to assess her causal contribution but also her moral accountability. According to this theory norm effects on causal selection are mediated by accountability judgments that are not only sensitive to the abnormality of behavior but also to mitigating factors, such as intentionality and knowledge of norms. Five experiments are presented that favor the accountability account over the two alternative theories. PMID:27591550

  6. Anatomy of an Accident.

    ERIC Educational Resources Information Center

    Mobley, Michael

    1984-01-01

    The findings of industrial safety engineers in the areas of accident causation and prevention are wholly applicable to adventure programs. Adventure education instructors can use safety engineering concepts to assess the risk in a particular activity, understand factors that cause accidents, and intervene to minimize injuries and damages if…

  7. Genetically-reduced serum ACE activity might be a causal risk factor for obstructive sleep apnea syndrome: A meta-analysis.

    PubMed

    He, Lan; Wang, Bin; Lang, Wei-Ya; Xue, Jing; Zhao, Da-Long; Li, Guo-Feng; Zheng, Li-Hong; Pan, Hong-Ming

    2015-01-01

    We meta-analytically summarized the associations of angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with ACE activity and obstructive sleep apnea syndrome (OSAS) to see whether ACE activity is causally associated with OSAS. Literature search and data abstraction were done in duplicate. Sixteen articles including 2060 OSAS patients and 1878 controls were summarized. Overall, no significance was observed for the association of I/D polymorphism with OSAS, whereas carriers of II genotype (weighted mean difference or WMD, 95% confidence interval or CI, P: -11.976, -17.168 to -6.783, <0.001) or I allele (-9.842, -14.766 to -4.918, <0.001) had a lower level of serum ACE activity compared with DD genotype carriers, respectively. In subgroup analyses, carriers of II genotype were 3.806 times more likely to develop OSAS (95% CI, P: 1.865 to 7.765, <0.001) in OSAS patients with hypertension, without heterogeneity. Mendelian randomization analysis indicated there was 37.4% (95% CI: 1.115 to 3.142) and 32.4% (1.106 to 2.845) increased risk of OSAS by a reduction of 1 U/L in ACE activity for the II genotype and I allele carriers versus DD genotype carriers, respectively. There was no observable publication bias. Collectively, genetically-reduced serum ACE activity might be a causal risk factor for OSAS. PMID:26486181

  8. The influence of biotic and abiotic factors on (137)Cs accumulation in higher fungi after the accident at Chernobyl NPP.

    PubMed

    Zarubina, N

    2016-09-01

    Levels of soil contamination with (137)Cs, the belonging of fungi to a certain ecological group, the localization depth of the main part of mycelium in soil are the primary factors influencing the value of (137)Cs specific activity in higher fungi after the accident at Chernobyl NPP. It has been found that the value of (137)Cs specific activity in fungi of one species could vary by more than 10 times during a vegetation period. A correlation between the changes of (137)Cs content in fungi during the vegetation period and the amount of precipitates during various periods preceding the collection of samples has not been determined. An assumption has been proposed stating dependence between peculiarities of mycelium growth during the vegetation period and the changes of (137)Cs specific activity in fungi. PMID:26690320

  9. The influence of biotic and abiotic factors on (137)Cs accumulation in higher fungi after the accident at Chernobyl NPP.

    PubMed

    Zarubina, N

    2016-09-01

    Levels of soil contamination with (137)Cs, the belonging of fungi to a certain ecological group, the localization depth of the main part of mycelium in soil are the primary factors influencing the value of (137)Cs specific activity in higher fungi after the accident at Chernobyl NPP. It has been found that the value of (137)Cs specific activity in fungi of one species could vary by more than 10 times during a vegetation period. A correlation between the changes of (137)Cs content in fungi during the vegetation period and the amount of precipitates during various periods preceding the collection of samples has not been determined. An assumption has been proposed stating dependence between peculiarities of mycelium growth during the vegetation period and the changes of (137)Cs specific activity in fungi.

  10. Comparing the Identification of Recommendations by Different Accident Investigators Using a Common Methodology

    NASA Technical Reports Server (NTRS)

    Johnson, Chris W.; Oltedal, H. A.; Holloway, C. M.

    2012-01-01

    Accident reports play a key role in the safety of complex systems. These reports present the recommendations that are intended to help avoid any recurrence of past failures. However, the value of these findings depends upon the causal analysis that helps to identify the reasons why an accident occurred. Various techniques have been developed to help investigators distinguish root causes from contributory factors and contextual information. This paper presents the results from a study into the individual differences that can arise when a group of investigators independently apply the same technique to identify the causes of an accident. This work is important if we are to increase the consistency and coherence of investigations following major accidents.

  11. Minor illness and injury: factors influencing attendance at a paediatric accident and emergency department

    PubMed Central

    Hendry, S; Beattie, T; Heaney, D

    2005-01-01

    Aims: To gather information on children with minor illness or injury presenting to a paediatric accident and emergency (A&E) department and the decision making process leading to their attendance. Methods: Prospective questionnaire based survey of 465 children selected by systematic sampling from A&E attenders allocated to the lowest triage category. Results: The study population was statistically representative of the total population of A&E attenders. The lower deprivation categories were over represented. Educational attainment, childcare experience, and parental coping skills were important in relation to A&E attendance. More children attended with injury as opposed to illness. There were no significant demographic differences between those children who presented directly to A&E and those who made prior contact with a GP. Just under half the study population had made contact with a general practitioner (GP) before attending A&E. The majority of those children were directly referred to A&E at that point. GPs referred equivalent numbers of children with illness and injury. Conclusions: Parents and GPs view paediatric A&E departments as an appropriate place to seek treatment for children with minor illness or injury. PMID:15908631

  12. Occupational accidents aboard merchant ships

    PubMed Central

    Hansen, H; Nielsen, D; Frydenberg, M

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may be initiated. Methods: The study is a historical follow up on occupational accidents among crew aboard Danish merchant ships in the period 1993–7. Data were extracted from the Danish Maritime Authority and insurance data. Exact data on time at risk were available. Results: A total of 1993 accidents were identified during a total of 31 140 years at sea. Among these, 209 accidents resulted in permanent disability of 5% or more, and 27 were fatal. The mean risk of having an occupational accident was 6.4/100 years at sea and the risk of an accident causing a permanent disability of 5% or more was 0.67/100 years aboard. Relative risks for notified accidents and accidents causing permanent disability of 5% or more were calculated in a multivariate analysis including ship type, occupation, age, time on board, change of ship since last employment period, and nationality. Foreigners had a considerably lower recorded rate of accidents than Danish citizens. Age was a major risk factor for accidents causing permanent disability. Change of ship and the first period aboard a particular ship were identified as risk factors. Walking from one place to another aboard the ship caused serious accidents. The most serious accidents happened on deck. Conclusions: It was possible to clearly identify work situations and specific risk factors for accidents aboard merchant ships. Most accidents happened while performing daily routine duties. Preventive measures should focus on workplace instructions for all important functions aboard and also on the prevention of accidents caused by walking around aboard the ship. PMID:11850550

  13. The Fukushima radiation accident: consequences for radiation accident medical management.

    PubMed

    Meineke, Viktor; Dörr, Harald

    2012-08-01

    The March 2011 radiation accident in Fukushima, Japan, is a textbook example of a radiation accident of global significance. In view of the global dimensions of the accident, it is important to consider the lessons learned. In this context, emphasis must be placed on consequences for planning appropriate medical management for radiation accidents including, for example, estimates of necessary human and material resources. The specific characteristics of the radiation accident in Fukushima are thematically divided into five groups: the exceptional environmental influences on the Fukushima radiation accident, particular circumstances of the accident, differences in risk perception, changed psychosocial factors in the age of the Internet and globalization, and the ignorance of the effects of ionizing radiation both among the general public and health care professionals. Conclusions like the need for reviewing international communication, interfacing, and interface definitions will be drawn from the Fukushima radiation accident. PMID:22951483

  14. The Fukushima radiation accident: consequences for radiation accident medical management.

    PubMed

    Meineke, Viktor; Dörr, Harald

    2012-08-01

    The March 2011 radiation accident in Fukushima, Japan, is a textbook example of a radiation accident of global significance. In view of the global dimensions of the accident, it is important to consider the lessons learned. In this context, emphasis must be placed on consequences for planning appropriate medical management for radiation accidents including, for example, estimates of necessary human and material resources. The specific characteristics of the radiation accident in Fukushima are thematically divided into five groups: the exceptional environmental influences on the Fukushima radiation accident, particular circumstances of the accident, differences in risk perception, changed psychosocial factors in the age of the Internet and globalization, and the ignorance of the effects of ionizing radiation both among the general public and health care professionals. Conclusions like the need for reviewing international communication, interfacing, and interface definitions will be drawn from the Fukushima radiation accident.

  15. Determination of Knowledge, Attitudes and Behaviors Regarding Factors Causing Home Accidents and Prevention in Mothers with a Child Aged 0-5 Years

    ERIC Educational Resources Information Center

    Akturk, Ümmühan; Erci, Behice

    2016-01-01

    Objective: In this study, it was aimed to determine knowledge, "attitudes" and "behaviors" in mothers with a child aged 0-5 years regarding factors causing "home accidents" and prevention. Method: The target population of the study consisted of mothers with a child aged 0-5 years who were admitted to pediatrics ward…

  16. Causal supports for early word learning.

    PubMed

    Booth, Amy E

    2009-01-01

    What factors determine whether a young child will learn a new word? Although there are surely numerous contributors, the current investigation highlights the role of causal information. Three-year-old children (N = 36) were taught 6 new words for unfamiliar objects or animals. Items were described in terms of their causal or noncausal properties. When tested only minutes after training, no significant differences between the conditions were evident. However, when tested several days after training, children performed better on words trained in the causal condition. These results demonstrate that the well-documented effect of causal information on learning and categorization extends to word learning in young children. PMID:19630905

  17. Long-term variation (1960-2003) and causal factors of non-point-source nitrogen and phosphorus in the upper reach of the Yangtze River.

    PubMed

    Shen, Zhenyao; Chen, Lei; Ding, Xiaowen; Hong, Qian; Liu, Ruimin

    2013-05-15

    The knowledge of long-term variation and causal factors of non-point source (NPS) pollution in large-scale watersheds is helpful in the development of water quality control programs. In this study, the Improved Export Coefficient Model and the Revised Universal Soil Loss Equation were combined to estimate the temporal and spatial variations (1960-2003) of NPS pollution in the upper reach of the Yangtze River (URYR). Two change points for NPS pollution were successfully detected. In the URYR, the dissolved nitrogen (DN) and dissolved phosphorus (DP) increased before 2000 and decreased after 2000, whereas the inflection points from increase to decline were around 1980 for the adsorbed N (AN) and adsorbed P (AP). The results also indicated that the dissolved pollutants were mainly contributed by the anthropogenic factors, while the adsorbed pollutants were primarily exported by the natural factors. By comparing the load intensities from each source, it revealed that for the dissolved pollutants, the major source of the high load intensity transferred from urban land to dry land after 1980. Simultaneously, the high load intensity areas of the adsorbed pollutants transferred from forest to orchard around 1980, which was mainly attributed to the increasing fertilizer application. These results may be useful for planning and management of the URYR and other large-scale watersheds.

  18. Preschoolers' Understanding of Temporal and Causal Relations.

    ERIC Educational Resources Information Center

    Sharp, Kay Colby

    1982-01-01

    Two experiments investigated psychological factors determining preschoolers' success or failure on a sequence-completion task involving temporal and causal ordering of events. Overall findings demonstrate that while preschoolers do understand temporal/causal relationships, their abilities are dependent on process variables demanded by the task…

  19. Routes to failure: analysis of 41 civil aviation accidents from the Republic of China using the human factors analysis and classification system.

    PubMed

    Li, Wen-Chin; Harris, Don; Yu, Chung-San

    2008-03-01

    The human factors analysis and classification system (HFACS) is based upon Reason's organizational model of human error. HFACS was developed as an analytical framework for the investigation of the role of human error in aviation accidents, however, there is little empirical work formally describing the relationship between the components in the model. This research analyses 41 civil aviation accidents occurring to aircraft registered in the Republic of China (ROC) between 1999 and 2006 using the HFACS framework. The results show statistically significant relationships between errors at the operational level and organizational inadequacies at both the immediately adjacent level (preconditions for unsafe acts) and higher levels in the organization (unsafe supervision and organizational influences). The pattern of the 'routes to failure' observed in the data from this analysis of civil aircraft accidents show great similarities to that observed in the analysis of military accidents. This research lends further support to Reason's model that suggests that active failures are promoted by latent conditions in the organization. Statistical relationships linking fallible decisions in upper management levels were found to directly affect supervisory practices, thereby creating the psychological preconditions for unsafe acts and hence indirectly impairing the performance of pilots, ultimately leading to accidents.

  20. Factors Associated with Fatal Occupational Accidents among Mexican Workers: A National Analysis

    PubMed Central

    Gonzalez-Delgado, Mery; Gómez-Dantés, Héctor; Fernández-Niño, Julián Alfredo; Robles, Eduardo; Borja, Víctor H.; Aguilar, Miriam

    2015-01-01

    Objective To identify the factors associated with fatal occupational injuries in Mexico in 2012 among workers affiliated with the Mexican Social Security Institute. Methods Analysis of secondary data using information from the National Occupational Risk Information System, with the consequence of the occupational injury (fatal versus non-fatal) as the response variable. The analysis included 406,222 non-fatal and 1,140 fatal injuries from 2012. The factors associated with the lethality of the injury were identified using a logistic regression model with the Firth approach. Results Being male (OR=5.86; CI95%: 4.22-8.14), age (OR=1.04; CI95%: 1.03-1.06), employed in the position for 1 to 10 years (versus less than 1 year) (OR=1.37; CI95%: 1.15-1.63), working as a facilities or machine operator or assembler (OR: 3.28; CI95%: 2.12- 5.07) and being a worker without qualifications (OR=1.96; CI95%: 1.18-3.24) (versus an office worker) were associated with fatality in the event of an injury. Additionally, companies classified as maximum risk (OR=1.90; CI 95%: 1.38-2.62), workplace conditions (OR=7.15; CI95%: 3.63-14.10) and factors related to the work environment (OR=9.18; CI95%:4.36-19.33) were identified as risk factors for fatality in the event of an occupational injury. Conclusions Fatality in the event of an occupational injury is associated with factors related to sociodemographics (age, sex and occupation), the work environment and workplace conditions. Worker protection policies should be created for groups with a higher risk of fatal occupational injuries in Mexico. PMID:25790063

  1. A review of causal factors and control measures for bloat in farmed salmonids with a suggested mechanism for the development of the condition.

    PubMed

    Anderson, C D

    2006-08-01

    A mechanism for the development of bloat in salmonids is proposed and explained in terms of the physiology of digestion and osmoregulation in fish. Understanding the causal factors for bloat enables control measures to be identified. In farmed salmonids, the chyme produced during the digestion of nutrient-rich pelleted foods that rapidly disintegrate in the stomach will be a potent activator of a negative feedback mechanism (enterogastric control), which slows stomach emptying to protect the small intestine from nutrient overload. In saline environments salmonids continuously drink sea water to replace fluid lost across the gills. Fluid loss is increased during periods of stress caused by factors such as low oxygen levels, elevated temperature or high salinity. When ingestion of nutrient-rich food results in prolonged activation of enterogastric control, slowed stomach emptying leads to decreased absorption of water, thirst and increased drinking. This further exacerbates stomach distention. The proposed mechanism for the development of bloat is supported by on-farm experience where measures to control bloat include reducing food intake, altering the composition of the diet and using appropriate strategies to reduce stress.

  2. Somatic symptoms in women 11 years after the Chornobyl accident: prevalence and risk factors.

    PubMed

    Bromet, Evelyn J; Gluzman, Semyon; Schwartz, Joseph E; Goldgaber, Dmitry

    2002-08-01

    Exposure to the Chornobyl nuclear power plant explosion resulted in widespread, persistent somatic complaints, but little is known about the nature and risk factors for these conditions. This study compares the health reports of 300 women evacuated to Kyiv from the contamination zone around the plant and 300 controls with a child in the same homeroom as the evacuees in 1997. The interview addressed somatic concerns, risk factors for poor health, and Chornobyl-related stress. Compared with controls, evacuees reported significantly more health problems and rated their health more poorly overall. These differences remained significant after controlling for demographic and clinical risk factors, including the tendency to amplify physical symptoms. Significantly more evacuees received a diagnosis of a Chornobyl-related illness by a local physician, believed that their health and their children's health had been adversely affected, and were positive for Chornobyl-induced post-traumatic stress disorder. After controlling for these Chornobyl stress variables, the differences in number of health problems commonly attributed to Chornobyl remained significant but differences in general health ratings did not. The perceptions of controls were similar to those of women in a national sample. The relationship between Chornobyl stress and illness was twice as strong in evacuees (odds ratio = 6.95) as in Kyiv controls (odds ratio = 3.34) and weakest in the national sample (odds ratio = 1.64). The results confirm the persistence and nonspecificity of the subjective medical consequences of Chornobyl and are consistent with the hypothesis that traumatic events exert their greatest negative impacts on health in vulnerable or disadvantaged groups.

  3. Risk-Based Causal Modeling of Airborne Loss of Separation

    NASA Technical Reports Server (NTRS)

    Geuther, Steven C.; Shih, Ann T.

    2015-01-01

    Maintaining safe separation between aircraft remains one of the key aviation challenges as the Next Generation Air Transportation System (NextGen) emerges. The goals of the NextGen are to increase capacity and reduce flight delays to meet the aviation demand growth through the 2025 time frame while maintaining safety and efficiency. The envisioned NextGen is expected to enable high air traffic density, diverse fleet operations in the airspace, and a decrease in separation distance. All of these factors contribute to the potential for Loss of Separation (LOS) between aircraft. LOS is a precursor to a potential mid-air collision (MAC). The NASA Airspace Operations and Safety Program (AOSP) is committed to developing aircraft separation assurance concepts and technologies to mitigate LOS instances, therefore, preventing MAC. This paper focuses on the analysis of causal and contributing factors of LOS accidents and incidents leading to MAC occurrences. Mid-air collisions among large commercial aircraft are rare in the past decade, therefore, the LOS instances in this study are for general aviation using visual flight rules in the years 2000-2010. The study includes the investigation of causal paths leading to LOS, and the development of the Airborne Loss of Separation Analysis Model (ALOSAM) using Bayesian Belief Networks (BBN) to capture the multi-dependent relations of causal factors. The ALOSAM is currently a qualitative model, although further development could lead to a quantitative model. ALOSAM could then be used to perform impact analysis of concepts and technologies in the AOSP portfolio on the reduction of LOS risk.

  4. Temporal uncertainty analysis of human errors based on interrelationships among multiple factors: a case of Minuteman III missile accident.

    PubMed

    Rong, Hao; Tian, Jin; Zhao, Tingdi

    2016-01-01

    In traditional approaches of human reliability assessment (HRA), the definition of the error producing conditions (EPCs) and the supporting guidance are such that some of the conditions (especially organizational or managerial conditions) can hardly be included, and thus the analysis is burdened with incomprehensiveness without reflecting the temporal trend of human reliability. A method based on system dynamics (SD), which highlights interrelationships among technical and organizational aspects that may contribute to human errors, is presented to facilitate quantitatively estimating the human error probability (HEP) and its related variables changing over time in a long period. Taking the Minuteman III missile accident in 2008 as a case, the proposed HRA method is applied to assess HEP during missile operations over 50 years by analyzing the interactions among the variables involved in human-related risks; also the critical factors are determined in terms of impact that the variables have on risks in different time periods. It is indicated that both technical and organizational aspects should be focused on to minimize human errors in a long run. PMID:26360211

  5. Temporal uncertainty analysis of human errors based on interrelationships among multiple factors: a case of Minuteman III missile accident.

    PubMed

    Rong, Hao; Tian, Jin; Zhao, Tingdi

    2016-01-01

    In traditional approaches of human reliability assessment (HRA), the definition of the error producing conditions (EPCs) and the supporting guidance are such that some of the conditions (especially organizational or managerial conditions) can hardly be included, and thus the analysis is burdened with incomprehensiveness without reflecting the temporal trend of human reliability. A method based on system dynamics (SD), which highlights interrelationships among technical and organizational aspects that may contribute to human errors, is presented to facilitate quantitatively estimating the human error probability (HEP) and its related variables changing over time in a long period. Taking the Minuteman III missile accident in 2008 as a case, the proposed HRA method is applied to assess HEP during missile operations over 50 years by analyzing the interactions among the variables involved in human-related risks; also the critical factors are determined in terms of impact that the variables have on risks in different time periods. It is indicated that both technical and organizational aspects should be focused on to minimize human errors in a long run.

  6. Human factors engineering in healthcare systems: the problem of human error and accident management.

    PubMed

    Cacciabue, P C; Vella, G

    2010-04-01

    This paper discusses some crucial issues associated with the exploitation of data and information about health care for the improvement of patient safety. In particular, the issues of human factors and safety management are analysed in relation to exploitation of reports about non-conformity events and field observations. A methodology for integrating field observation and theoretical approaches for safety studies is described. Two sample cases are discussed in detail: the first one makes reference to the use of data collected in the aviation domain and shows how these can be utilised to define hazard and risk; the second one concerns a typical ethnographic study in a large hospital structure for the identification of most relevant areas of intervention. The results show that, if national authorities find a way to harmonise and formalize critical aspects, such as the severity of standard events, it is possible to estimate risk and define auditing needs, well before the occurrence of serious incidents, and to indicate practical ways forward for improving safety standards.

  7. Embeddings of Causal Sets

    SciTech Connect

    Reid, David D.

    2009-07-06

    A key postulate of the causal set program is that this discrete partial order offers a sufficiently rich structure to make it a viable model of spacetime for quantum gravity. If the deep structure of spacetime is that of a causal set, then the correspondence principle (with the spacetimes of general relativity) must be obeyed. Therefore, one of the requirements of this program is to establish that the causal set structure is in fact, not just in principle, fully consistent with our macroscopic notion of spacetime as a Lorentzian manifold. An important component of any such 'manifold test' is the ability to find embeddings of causal sets into Lorentzian manifolds.

  8. Accident/Mishap Investigation System

    NASA Technical Reports Server (NTRS)

    Keller, Richard; Wolfe, Shawn; Gawdiak, Yuri; Carvalho, Robert; Panontin, Tina; Williams, James; Sturken, Ian

    2007-01-01

    InvestigationOrganizer (IO) is a Web-based collaborative information system that integrates the generic functionality of a database, a document repository, a semantic hypermedia browser, and a rule-based inference system with specialized modeling and visualization functionality to support accident/mishap investigation teams. This accessible, online structure is designed to support investigators by allowing them to make explicit, shared, and meaningful links among evidence, causal models, findings, and recommendations.

  9. Determining Stochasticity and Causality of Vegetation Dynamics in the Southwestern Amazon: Non-linear Time Series Analysis and Dynamic Factor Analysis of EVI2 Data

    NASA Astrophysics Data System (ADS)

    Klarenberg, G.

    2015-12-01

    Infrastructure projects such as road paving have proven to bring a variety of (mainly) socio-economic advantages to countries and populations. However, many studies have also highlighted the negative socio-economic and biophysical effects that these developments have at local, regional and even larger scales. The "MAP" area (Madre de Dios in Peru, Acre in Brazil, and Pando in Bolivia) is a biodiversity hotspot in the southwestern Amazon where sections of South America's Inter-Oceanic Highway were paved between 2006 and 2010. We are interested in vegetation dynamics in the area since it plays an important role in ecosystem functions and ecosystem services in socio-ecological systems: it provides information on productivity and structure of the forest. In preparation of more complex and mechanistic simulation of vegetation, non-linear time series analysis and Dynamic Factor Analysis (DFA) was conducted on Enhanced Vegetation Index (EVI) time series - which is a remote sensing product and provides information on vegetation dynamics as it detects chlorophyll (productivity) and structural change. Time series of 30 years for EVI2 (from MODIS and AVHRR) were obtained for 100 communities in the area. Through specific time series cluster analysis of the vegetation data, communities were clustered to facilitate data analysis and pattern recognition. The clustering is spatially consistent, and appears to be driven by median road paving progress - which is different for each cluster. Non-linear time series analysis (multivariate singular spectrum analysis, MSSA) separates common signals (or low-dimensional attractors) across clusters. Despite the presence of this deterministic structure though, time series behavior is mostly stochastic. Granger causality analysis between EVI2 and possible response variables indicates which variables (and with what lags) are to be included in DFA, resulting in unique Dynamic Factor Models for each cluster.

  10. The Time-Dependent Transfer Factor of Radiocesium from Soil to Game Animals in Japan after the Fukushima Dai-ichi Nuclear Accident.

    PubMed

    Tagami, Keiko; Howard, Brenda J; Uchida, Shigeo

    2016-09-01

    Since the Fukushima Dai-ichi accident, monitoring of tissues from hunted game animals ensures compliance with the standard food limits for radionuclides in Japan. We quantified the transfer of (137)Cs from contaminated land to game animals using the Aggregated transfer factor (Tag = activity concentration in meat [Bq kg(-1) fw]/amount in soil [Bq m(-2)]) of (137)Cs for Asian black bear, wild boar, sika deer, green pheasant, copper pheasant and wild duck, collected between 2011 and 2015. Open data sources were used from Fukushima, Miyagi, Ibaraki, Tochigi, and Gunma prefectures. Our initially compiled data showed that the maximum reported (137)Cs activity concentration in wild boar after the Fukushima Dai-ichi accident were lower than those reported after the Chernobyl accident. The geometric mean Tag values (m(2)kg(-1) fw) of (137)Cs in 2015 for Asian black bear, wild boar, sika deer and copper pheasant were similar (1.9-5.1) × 10(-3) while those for green pheasant and wild duck were about 1 order of magnitude lower at (1.0-2.2) × 10(-4). Effective half-lives were 1.2-6.9 y except for sika deer and copper pheasant where no decreases were found. In contrast to the Chernobyl accident, no seasonal change occurred in the meat (137)Cs activity concentrations of the wild animals during the study period.

  11. The Time-Dependent Transfer Factor of Radiocesium from Soil to Game Animals in Japan after the Fukushima Dai-ichi Nuclear Accident.

    PubMed

    Tagami, Keiko; Howard, Brenda J; Uchida, Shigeo

    2016-09-01

    Since the Fukushima Dai-ichi accident, monitoring of tissues from hunted game animals ensures compliance with the standard food limits for radionuclides in Japan. We quantified the transfer of (137)Cs from contaminated land to game animals using the Aggregated transfer factor (Tag = activity concentration in meat [Bq kg(-1) fw]/amount in soil [Bq m(-2)]) of (137)Cs for Asian black bear, wild boar, sika deer, green pheasant, copper pheasant and wild duck, collected between 2011 and 2015. Open data sources were used from Fukushima, Miyagi, Ibaraki, Tochigi, and Gunma prefectures. Our initially compiled data showed that the maximum reported (137)Cs activity concentration in wild boar after the Fukushima Dai-ichi accident were lower than those reported after the Chernobyl accident. The geometric mean Tag values (m(2)kg(-1) fw) of (137)Cs in 2015 for Asian black bear, wild boar, sika deer and copper pheasant were similar (1.9-5.1) × 10(-3) while those for green pheasant and wild duck were about 1 order of magnitude lower at (1.0-2.2) × 10(-4). Effective half-lives were 1.2-6.9 y except for sika deer and copper pheasant where no decreases were found. In contrast to the Chernobyl accident, no seasonal change occurred in the meat (137)Cs activity concentrations of the wild animals during the study period. PMID:27513196

  12. Analysis of avalanche risk factors in backcountry terrain based on usage frequency and accident data in Switzerland

    NASA Astrophysics Data System (ADS)

    Techel, F.; Zweifel, B.; Winkler, K.

    2015-09-01

    Recreational activities in snow-covered mountainous terrain in the backcountry account for the vast majority of avalanche accidents. Studies analyzing avalanche risk mostly rely on accident statistics without considering exposure (or the elements at risk), i.e., how many, when and where people are recreating, as data on recreational activity in the winter mountains are scarce. To fill this gap, we explored volunteered geographic information on two social media mountaineering websites - bergportal.ch and camptocamp.org. Based on these data, we present a spatiotemporal pattern of winter backcountry touring activity in the Swiss Alps and compare this with accident statistics. Geographically, activity was concentrated in Alpine regions relatively close to the main Swiss population centers in the west and north. In contrast, accidents occurred equally often in the less-frequented inner-alpine regions. Weekends, weather and avalanche conditions influenced the number of recreationists, while the odds to be involved in a severe avalanche accident did not depend on weekends or weather conditions. However, the likelihood of being involved in an accident increased with increasing avalanche danger level, but also with a more unfavorable snowpack containing persistent weak layers (also referred to as an old snow problem). In fact, the most critical situation for backcountry recreationists and professionals occurred on days and in regions when both the avalanche danger was critical and when the snowpack contained persistent weak layers. The frequently occurring geographical pattern of a more unfavorable snowpack structure also explains the relatively high proportion of accidents in the less-frequented inner-alpine regions. These results have practical implications: avalanche forecasters should clearly communicate the avalanche danger and the avalanche problem to the backcountry user, particularly if persistent weak layers are of concern. Professionals and recreationists, on the

  13. Causal Learning Across Domains

    ERIC Educational Resources Information Center

    Schulz, Laura E.; Gopnik, Alison

    2004-01-01

    Five studies investigated (a) children's ability to use the dependent and independent probabilities of events to make causal inferences and (b) the interaction between such inferences and domain-specific knowledge. In Experiment 1, preschoolers used patterns of dependence and independence to make accurate causal inferences in the domains of…

  14. Causality in Classical Electrodynamics

    ERIC Educational Resources Information Center

    Savage, Craig

    2012-01-01

    Causality in electrodynamics is a subject of some confusion, especially regarding the application of Faraday's law and the Ampere-Maxwell law. This has led to the suggestion that we should not teach students that electric and magnetic fields can cause each other, but rather focus on charges and currents as the causal agents. In this paper I argue…

  15. Repeated Causal Decision Making

    ERIC Educational Resources Information Center

    Hagmayer, York; Meder, Bjorn

    2013-01-01

    Many of our decisions refer to actions that have a causal impact on the external environment. Such actions may not only allow for the mere learning of expected values or utilities but also for acquiring knowledge about the causal structure of our world. We used a repeated decision-making paradigm to examine what kind of knowledge people acquire in…

  16. Agency, time, and causality

    PubMed Central

    Widlok, Thomas

    2014-01-01

    Cognitive Scientists interested in causal cognition increasingly search for evidence from non-Western Educational Industrial Rich Democratic people but find only very few cross-cultural studies that specifically target causal cognition. This article suggests how information about causality can be retrieved from ethnographic monographs, specifically from ethnographies that discuss agency and concepts of time. Many apparent cultural differences with regard to causal cognition dissolve when cultural extensions of agency and personhood to non-humans are taken into account. At the same time considerable variability remains when we include notions of time, linearity and sequence. The article focuses on ethnographic case studies from Africa but provides a more general perspective on the role of ethnography in research on the diversity and universality of causal cognition. PMID:25414683

  17. Anthropotechnological analysis of industrial accidents in Brazil.

    PubMed Central

    Binder, M. C.; de Almeida, I. M.; Monteau, M.

    1999-01-01

    The Brazilian Ministry of Labour has been attempting to modify the norms used to analyse industrial accidents in the country. For this purpose, in 1994 it tried to make compulsory use of the causal tree approach to accident analysis, an approach developed in France during the 1970s, without having previously determined whether it is suitable for use under the industrial safety conditions that prevail in most Brazilian firms. In addition, opposition from Brazilian employers has blocked the proposed changes to the norms. The present study employed anthropotechnology to analyse experimental application of the causal tree method to work-related accidents in industrial firms in the region of Botucatu, São Paulo. Three work-related accidents were examined in three industrial firms representative of local, national and multinational companies. On the basis of the accidents analysed in this study, the rationale for the use of the causal tree method in Brazil can be summarized for each type of firm as follows: the method is redundant if there is a predominance of the type of risk whose elimination or neutralization requires adoption of conventional industrial safety measures (firm representative of local enterprises); the method is worth while if the company's specific technical risks have already largely been eliminated (firm representative of national enterprises); and the method is particularly appropriate if the firm has a good safety record and the causes of accidents are primarily related to industrial organization and management (multinational enterprise). PMID:10680249

  18. Radiotherapy Accidents

    NASA Astrophysics Data System (ADS)

    Mckenzie, Alan

    A major benefit of a Quality Assurance system in a radiotherapy centre is that it reduces the likelihood of an accident. For over 20 years I have been the interface in the UK between the Institute of Physics and Engineering in Medicine and the media — newspapers, radio and TV — and so I have learned about radiotherapy accidents from personal experience. In some cases, these accidents did not become public and so the hospital cannot be identified. Nevertheless, lessons are still being learned.

  19. Equipment failures and their contribution to industrial incidents and accidents in the manufacturing industry.

    PubMed

    Bourassa, Dominic; Gauthier, François; Abdul-Nour, Georges

    2016-01-01

    Accidental events in manufacturing industries can be caused by many factors, including work methods, lack of training, equipment design, maintenance and reliability. This study is aimed at determining the contribution of failures of commonly used industrial equipment, such as machines, tools and material handling equipment, to the chain of causality of industrial accidents and incidents. Based on a case study which aimed at the analysis of an existing pulp and paper company's accident database, this paper examines the number, type and gravity of the failures involved in these events and their causes. Results from this study show that equipment failures had a major effect on the number and severity of accidents accounted for in the database: 272 out of 773 accidental events were related to equipment failure, where 13 of them had direct human consequences. Failures that contributed directly or indirectly to these events are analyzed.

  20. Causal Networks or Causal Islands? The Representation of Mechanisms and the Transitivity of Causal Judgment

    ERIC Educational Resources Information Center

    Johnson, Samuel G. B.; Ahn, Woo-kyoung

    2015-01-01

    Knowledge of mechanisms is critical for causal reasoning. We contrasted two possible organizations of causal knowledge--an interconnected causal "network," where events are causally connected without any boundaries delineating discrete mechanisms; or a set of disparate mechanisms--causal "islands"--such that events in different…

  1. Underweight as a risk factor for respiratory death in the Whitehall cohort study: exploring reverse causality using a 45-year follow-up.

    PubMed

    Kivimäki, Mika; Shipley, Martin J; Bell, Joshua A; Brunner, Eric J; Batty, G David; Singh-Manoux, Archana

    2016-01-01

    Underweight adults have higher rates of respiratory death than the normal weight but it is unclear whether this association is causal or reflects illness-induced weight loss (reverse causality). Evidence from a 45-year follow-up of underweight participants for respiratory mortality in the Whitehall study (N=18 823; 2139 respiratory deaths) suggests that excess risk among the underweight is attributable to reverse causality. The age-adjusted and smoking-adjusted risk was 1.55-fold (95% CI 1.32 to 1.83) higher among underweight compared with normal weight participants, but attenuated in a stepwise manner to 1.14 (95% CI 0.76 to 1.71) after serial exclusions of deaths during the first 5-35 years of follow-up (P(trend)<0.001).

  2. Warp drive and causality

    NASA Astrophysics Data System (ADS)

    Everett, Allen E.

    1996-06-01

    Alcubierre recently exhibited a spacetime which, within the framework of general relativity, allows travel at superluminal speeds if matter with a negative energy density can exist, and conjectured that it should be possible to use similar techniques to construct a theory containing closed causal loops and, thus, travel backwards in time. We verify this conjecture by exhibiting a simple modification of Alcubierre's model, requiring no additional assumptions, in which causal loops are possible. We also note that this mechanism for generating causal loops differs in essential ways from that discovered by Gott involving cosmic strings.

  3. Type A Accident Investigation Board report on the January 17, 1996, electrical accident with injury in Technical Area 21 Tritium Science and Fabrication Facility Los Alamos National Laboratory. Final report

    SciTech Connect

    1996-04-01

    An electrical accident was investigated in which a crafts person received serious injuries as a result of coming into contact with a 13.2 kilovolt (kV) electrical cable in the basement of Building 209 in Technical Area 21 (TA-21-209) in the Tritium Science and Fabrication Facility (TSFF) at Los Alamos National Laboratory (LANL). In conducting its investigation, the Accident Investigation Board used various analytical techniques, including events and causal factor analysis, barrier analysis, change analysis, fault tree analysis, materials analysis, and root cause analysis. The board inspected the accident site, reviewed events surrounding the accident, conducted extensive interviews and document reviews, and performed causation analyses to determine the factors that contributed to the accident, including any management system deficiencies. Relevant management systems and factors that could have contributed to the accident were evaluated in accordance with the guiding principles of safety management identified by the Secretary of Energy in an October 1994 letter to the Defense Nuclear Facilities Safety Board and subsequently to Congress.

  4. Factors affecting vertical distribution of Fukushima accident-derived radiocesium in soil under different land-use conditions.

    PubMed

    Koarashi, Jun; Atarashi-Andoh, Mariko; Matsunaga, Takeshi; Sato, Tsutomu; Nagao, Seiya; Nagai, Haruyasu

    2012-08-01

    The Fukushima Dai-ichi nuclear power plant accident in Japan, triggered by a big earthquake and the resulting tsunami on 11 March 2011, caused a substantial release of radiocesium ((137)Cs and (134)Cs) and a subsequent contamination of soils in a range of terrestrial ecosystems. Identifying factors and processes affecting radiocesium retention in these soils is essential to predict how the deposited radiocesium will migrate through the soil profile and to other biological components. We investigated vertical distributions of radiocesium and physicochemical properties in soils (to 20 cm depth) at 15 locations under different land-use types (croplands, grasslands, and forests) within a 2 km × 2 km mesh area in Fukushima city. The total (137)Cs inventory deposited onto and into soil was similar (58.4±9.6 kBq m(-2)) between the three different land-use types. However, aboveground litter layer at the forest sites and herbaceous vegetation at the non-forested sites contributed differently to the total (137)Cs inventory. At the forest sites, 50-91% of the total inventory was observed in the litter layer. The aboveground vegetation contribution was in contrast smaller (<35%) at the other sites. Another remarkable difference was found in vertical distribution of (137)Cs in mineral soil layers; (137)Cs penetrated deeper in the forest soil profiles than in the non-forested soil profiles. We quantified (137)Cs retention at surface soil layers, and showed that higher (137)Cs retention can be explained in part by larger amounts of silt- and clay-sized particles in the layers. More importantly, the (137)Cs retention highly and negatively correlated with soil organic carbon content divided by clay content across all land-use types. The results suggest that organic matter inhibits strong adsorption of (137)Cs on clay minerals in surface soil layers, and as a result affects the vertical distribution and thus the mobility of (137)Cs in soil, particularly in the forest ecosystems.

  5. Reduction factors for wooden houses due to external γ-radiation based on in situ measurements after the Fukushima nuclear accident.

    PubMed

    Yoshida-Ohuchi, Hiroko; Hosoda, Masahiro; Kanagami, Takashi; Uegaki, Masaki; Tashima, Hideo

    2014-12-18

    For estimation of residents' exposure dose after a nuclear accident, the reduction factor, which is the ratio of the indoor dose to the outdoor dose is essential, as most individuals spend a large portion of their time indoors. After the Fukushima nuclear accident, we evaluated the median reduction factor with an interquartile range of 0.43 (0.34-0.53) based on 522 survey results for 69 detached wooden houses in two evacuation zones, Iitate village and Odaka district. The results indicated no statistically significant difference in the median reduction factor to the representative value of 0.4 given in the International Atomic Energy Agency (IAEA)-TECDOC-225 and 1162. However, with regard to the representative range of the reduction factor, we recommend the wider range of 0.2 to 0.7 or at least 0.2 to 0.6, which covered 87.7% and 80.7% of the data, respectively, rather than 0.2 to 0.5 given in the IAEA document, which covered only 66.5% of the data. We found that the location of the room within the house and area topography, and the use of cement roof tiles had the greatest influence on the reduction factor.

  6. Reduction factors for wooden houses due to external γ-radiation based on in situ measurements after the Fukushima nuclear accident

    PubMed Central

    Yoshida-Ohuchi, Hiroko; Hosoda, Masahiro; Kanagami, Takashi; Uegaki, Masaki; Tashima, Hideo

    2014-01-01

    For estimation of residents' exposure dose after a nuclear accident, the reduction factor, which is the ratio of the indoor dose to the outdoor dose is essential, as most individuals spend a large portion of their time indoors. After the Fukushima nuclear accident, we evaluated the median reduction factor with an interquartile range of 0.43 (0.34–0.53) based on 522 survey results for 69 detached wooden houses in two evacuation zones, Iitate village and Odaka district. The results indicated no statistically significant difference in the median reduction factor to the representative value of 0.4 given in the International Atomic Energy Agency (IAEA)-TECDOC-225 and 1162. However, with regard to the representative range of the reduction factor, we recommend the wider range of 0.2 to 0.7 or at least 0.2 to 0.6, which covered 87.7% and 80.7% of the data, respectively, rather than 0.2 to 0.5 given in the IAEA document, which covered only 66.5% of the data. We found that the location of the room within the house and area topography, and the use of cement roof tiles had the greatest influence on the reduction factor. PMID:25519512

  7. An influential factor for external radiation dose estimation for residents after the Fukushima Daiichi Nuclear Power Plant accident-time spent outdoors for residents in Iitate Village.

    PubMed

    Ishikawa, Tetsuo; Yasumura, Seiji; Ohtsuru, Akira; Sakai, Akira; Akahane, Keiichi; Yonai, Shunsuke; Sakata, Ritsu; Ozasa, Kotaro; Hayashi, Masayuki; Ohira, Tetsuya; Kamiya, Kenji; Abe, Masafumi

    2016-06-01

    Many studies have been conducted on radiation doses to residents after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Time spent outdoors is an influential factor for external dose estimation. Since little information was available on actual time spent outdoors for residents, different values of average time spent outdoors per day have been used in dose estimation studies on the FDNPP accident. The most conservative value of 24 h was sometimes used, while 2.4 h was adopted for indoor workers in the UNSCEAR 2013 report. Fukushima Medical University has been estimating individual external doses received by residents as a part of the Fukushima Health Management Survey by collecting information on the records of moves and activities (the Basic Survey) after the accident from each resident. In the present study, these records were analyzed to estimate an average time spent outdoors per day. As an example, in Iitate Village, its arithmetic mean was 2.08 h (95% CI: 1.64-2.51) for a total of 170 persons selected from respondents to the Basic Survey. This is a much smaller value than commonly assumed. When 2.08 h is used for the external dose estimation, the dose is about 25% (23-26% when using the above 95% CI) less compared with the dose estimated for the commonly used value of 8 h.

  8. An influential factor for external radiation dose estimation for residents after the Fukushima Daiichi Nuclear Power Plant accident-time spent outdoors for residents in Iitate Village.

    PubMed

    Ishikawa, Tetsuo; Yasumura, Seiji; Ohtsuru, Akira; Sakai, Akira; Akahane, Keiichi; Yonai, Shunsuke; Sakata, Ritsu; Ozasa, Kotaro; Hayashi, Masayuki; Ohira, Tetsuya; Kamiya, Kenji; Abe, Masafumi

    2016-06-01

    Many studies have been conducted on radiation doses to residents after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Time spent outdoors is an influential factor for external dose estimation. Since little information was available on actual time spent outdoors for residents, different values of average time spent outdoors per day have been used in dose estimation studies on the FDNPP accident. The most conservative value of 24 h was sometimes used, while 2.4 h was adopted for indoor workers in the UNSCEAR 2013 report. Fukushima Medical University has been estimating individual external doses received by residents as a part of the Fukushima Health Management Survey by collecting information on the records of moves and activities (the Basic Survey) after the accident from each resident. In the present study, these records were analyzed to estimate an average time spent outdoors per day. As an example, in Iitate Village, its arithmetic mean was 2.08 h (95% CI: 1.64-2.51) for a total of 170 persons selected from respondents to the Basic Survey. This is a much smaller value than commonly assumed. When 2.08 h is used for the external dose estimation, the dose is about 25% (23-26% when using the above 95% CI) less compared with the dose estimated for the commonly used value of 8 h. PMID:27034103

  9. Major Factors Affecting Incidence of Childhood Thyroid Cancer in Belarus after the Chernobyl Accident: Do Nitrates in Drinking Water Play a Role?

    PubMed Central

    Drozd, Valentina M.; Saenko, Vladimir A.; Brenner, Alina V.; Drozdovitch, Vladimir; Pashkevich, Vasilii I.; Kudelsky, Anatoliy V.; Demidchik, Yuri E.; Branovan, Igor; Shiglik, Nikolay; Rogounovitch, Tatiana I.; Yamashita, Shunichi; Biko, Johannes; Reiners, Christoph

    2015-01-01

    One of the major health consequences of the Chernobyl Nuclear Power Plant accident in 1986 was a dramatic increase in incidence of thyroid cancer among those who were aged less than 18 years at the time of the accident. This increase has been directly linked in several analytic epidemiological studies to iodine-131 (131I) thyroid doses received from the accident. However, there remains limited understanding of factors that modify the 131I-related risk. Focusing on post-Chernobyl pediatric thyroid cancer in Belarus, we reviewed evidence of the effects of radiation, thyroid screening, and iodine deficiency on regional differences in incidence rates of thyroid cancer. We also reviewed current evidence on content of nitrate in groundwater and thyroid cancer risk drawing attention to high levels of nitrates in open well water in several contaminated regions of Belarus, i.e. Gomel and Brest, related to the usage of nitrogen fertilizers. In this hypothesis generating study, based on ecological data and biological plausibility, we suggest that nitrate pollution may modify the radiation-related risk of thyroid cancer contributing to regional differences in rates of pediatric thyroid cancer in Belarus. Analytic epidemiological studies designed to evaluate joint effect of nitrate content in groundwater and radiation present a promising avenue of research and may provide useful insights into etiology of thyroid cancer. PMID:26397978

  10. Major Factors Affecting Incidence of Childhood Thyroid Cancer in Belarus after the Chernobyl Accident: Do Nitrates in Drinking Water Play a Role?

    PubMed

    Drozd, Valentina M; Saenko, Vladimir A; Brenner, Alina V; Drozdovitch, Vladimir; Pashkevich, Vasilii I; Kudelsky, Anatoliy V; Demidchik, Yuri E; Branovan, Igor; Shiglik, Nikolay; Rogounovitch, Tatiana I; Yamashita, Shunichi; Biko, Johannes; Reiners, Christoph

    2015-01-01

    One of the major health consequences of the Chernobyl Nuclear Power Plant accident in 1986 was a dramatic increase in incidence of thyroid cancer among those who were aged less than 18 years at the time of the accident. This increase has been directly linked in several analytic epidemiological studies to iodine-131 (131I) thyroid doses received from the accident. However, there remains limited understanding of factors that modify the 131I-related risk. Focusing on post-Chernobyl pediatric thyroid cancer in Belarus, we reviewed evidence of the effects of radiation, thyroid screening, and iodine deficiency on regional differences in incidence rates of thyroid cancer. We also reviewed current evidence on content of nitrate in groundwater and thyroid cancer risk drawing attention to high levels of nitrates in open well water in several contaminated regions of Belarus, i.e. Gomel and Brest, related to the usage of nitrogen fertilizers. In this hypothesis generating study, based on ecological data and biological plausibility, we suggest that nitrate pollution may modify the radiation-related risk of thyroid cancer contributing to regional differences in rates of pediatric thyroid cancer in Belarus. Analytic epidemiological studies designed to evaluate joint effect of nitrate content in groundwater and radiation present a promising avenue of research and may provide useful insights into etiology of thyroid cancer.

  11. The child accident repeater: a review.

    PubMed

    Jones, J G

    1980-04-01

    The child accident repeater is defined as one who has at least three accidents that come to medical attention within a year. The accident situation has features in common with those of the child who has a single accident through simple "bad luck", but other factors predispose him to repeated injury. In the child who has a susceptible personality, a tendency for accident repetition may be due to a breakdown in adjustment to a stressful environment. Prevention of repeat accidents should involve the usual measures considered appropriate for all children as well as an attempt to provide treatment of significant maladjustment and modification of a stressful environment.

  12. Down syndrome clusters in Germany after the Chernobyl accident

    SciTech Connect

    Burkart, W.; Grosche, B.; Schoetzau, A.

    1997-03-01

    In two independent studies using different approaches and covering West Berlin and Bavaria, respectively, highly significant temporal clusters of Down syndrome were found. Both sharp increases occurred in areas receiving relatively low Chernobyl fallout and concomitant radiation exposures. Only for the Berlin cluster was fallout present at the time of the affected meiosis, whereas the Nuremberg cluster preceded the radioactive contamination by 1 month. Hypotheses on possible causal relationships are compared. Radiation from the Chernobyl accident is an unlikely factor, because the associated cumulative dose was so low in comparison with natural background. Microdosimetric considerations would indicate that fewer than 1 in 200 oocyte nuclei would have experienced an ionizing event from Chernobyl radioactivity. Given the lack of understanding of what causes Down syndrome, other than factors associated with increased maternal age, additional research into environmental and infectious risk factors is warranted. 23 refs., 4 figs., 2 tabs.

  13. Comprehensive Analysis of Two Downburst-Related Aircraft Accidents

    NASA Technical Reports Server (NTRS)

    Shen, J.; Parks, E. K.; Bach, R. E.

    1996-01-01

    Although downbursts have been identified as the major cause of a number of aircraft takeoff and landing accidents, only the 1985 Dallas/Fort Worth (DFW) and the more recent (July 1994) Charlotte, North Carolina, landing accidents provided sufficient onboard recorded data to perform a comprehensive analysis of the downburst phenomenon. The first step in the present analysis was the determination of the downburst wind components. Once the wind components and their gradients were determined, the degrading effect of the wind environment on the airplane's performance was calculated. This wind-shear-induced aircraft performance degradation, sometimes called the F-factor, was broken down into two components F(sub 1) and F(sub 2), representing the effect of the horizontal wind gradient and the vertical wind velocity, respectively. In both the DFW and Charlotte cases, F(sub 1) was found to be the dominant causal factor of the accident. Next, the aircraft in the two cases were mathematically modeled using the longitudinal equations of motion and the appropriate aerodynamic parameters. Based on the aircraft model and the determined winds, the aircraft response to the recorded pilot inputs showed good agreement with the onboard recordings. Finally, various landing abort strategies were studied. It was concluded that the most acceptable landing abort strategy from both an analytical and pilot's standpoint was to hold constant nose-up pitch attitude while operating at maximum engine thrust.

  14. Safer approaches and landings: A multivariate analysis of critical factors

    NASA Astrophysics Data System (ADS)

    Heinrich, Durwood J.

    The approach-and-landing phases of flight represent 27% of mission time while resulting in 61 of the accidents and 39% of the fatalities. The landing phase itself represents only 1% of flight time but claims 45% of the accidents. Inadequate crew situation awareness (SA), crew resource management (CRM), and crew decision-making (DM) have been implicated in 51%, 63%, and 73% respectively of these accidents. The human factors constructs of SA, CRM, and DM were explored; a comprehensive definition of SA was proposed; and a "proactive defense" safety strategy was recommended. Data from a 1997 analysis of worldwide fatal accidents by the Flight Safety Foundation (FSF) Approach-and-Landing Accident Reduction (ALAR) Task Force was used to isolate crew- and weather-related causal factors that lead to approach-and-landing accidents (ALAs). Logistic regression and decision tree analysis were used on samplings of NASA's Aviation Safety Reporting System (ASRS) incident records ("near misses") and the National Transportation Safety Board's (NTSB) accident reports to examine hypotheses regarding factors and factor combinations that can dramatically increase the opportunity for accidents. An effective scale of risk factors was introduced for use by crews to proactively counter safety-related error-chain situations.

  15. Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - summary report

    SciTech Connect

    Gerton, R.E.

    1997-08-07

    This report is a summary of the Accident Investigation Board Report on the May 14, 1997, Chemical Explosion at the Plutonium Reclamation Facility, Hanford Site, Richland, Washington (DOE/RL-97-59). The referenced report provides a greater level of detail and includes a complete discussion of the facts identified, analysis of those facts, conclusions derived from the analysis, identification of the accident`s causal factors, and recommendations that should be addressed through follow-up action by the U.S. Department of Energy and its contractors. This companion document provides a concise summary of that report, with emphasis on management issues. Evaluation of emergency and occupational health response to, and radiological and chemical releases from, this accident was not within the scope of this investigation, but is the subject of a separate investigation and report (see DOE/RL-97-62).

  16. Considerations on causality in pharmacovigilance.

    PubMed

    Edwards, I Ralph

    2012-01-01

    Causality has been a topic of debate by philosophers, scientists, lawyers and for centuries. It is essential to define as precisely as possible all steps in the logical chain of events, since each may strengthen or confound an argument. Almost always there are issues of missing and conflicting data that need to be addressed specifically. In pharmacovigilance, as in many other situations, there is not just one possible causation for an effect but several. Each must be evaluated in the given context for probability. There is also likely to be a causal chain of events to the adverse effect under consideration, and each must be considered. In an individual patient diagnosis the components of patient history, clinical findings and various laboratory test findings are combined to point to the probability of the patho-physiological diagnosis, which in turn is related to possible causes with a strength determined by the constellation of findings. The established Bradford-Hill criteria are valuable in considering all the possible causal factors. Pharmacoepidemiology allows for population incidences of causes for particular effects and therefore provides an a priori probability listing for competing possible causes, or at least of one possible cause against the background of all others in a control group. Since adverse effects of medicines are generally rare, it is not possible to exclude drug causation in an individual by reliance on epidemiological evidence alone, only to argue that the incidence is below a level determined by statistical power, of the study or studies combined. Other areas of society are concerned with the process of causal inference, and this is especially true in legal cases in which judgements are made on possible personal injury by drugs.

  17. Illness causal beliefs in Turkish immigrants

    PubMed Central

    Minas, Harry; Klimidis, Steven; Tuncer, Can

    2007-01-01

    Background People hold a wide variety of beliefs concerning the causes of illness. Such beliefs vary across cultures and, among immigrants, may be influenced by many factors, including level of acculturation, gender, level of education, and experience of illness and treatment. This study examines illness causal beliefs in Turkish-immigrants in Australia. Methods Causal beliefs about somatic and mental illness were examined in a sample of 444 members of the Turkish population of Melbourne. The socio-demographic characteristics of the sample were broadly similar to those of the Melbourne Turkish community. Five issues were examined: the structure of causal beliefs; the relative frequency of natural, supernatural and metaphysical beliefs; ascription of somatic, mental, or both somatic and mental conditions to the various causes; the correlations of belief types with socio-demographic, modernizing and acculturation variables; and the relationship between causal beliefs and current illness. Results Principal components analysis revealed two broad factors, accounting for 58 percent of the variation in scores on illness belief scales, distinctly interpretable as natural and supernatural beliefs. Second, beliefs in natural causes were more frequent than beliefs in supernatural causes. Third, some causal beliefs were commonly linked to both somatic and mental conditions while others were regarded as more specific to either somatic or mental disorders. Last, there was a range of correlations between endorsement of belief types and factors defining heterogeneity within the community, including with demographic factors, indicators of modernizing and acculturative processes, and the current presence of illness. Conclusion Results supported the classification of causal beliefs proposed by Murdock, Wilson & Frederick, with a division into natural and supernatural causes. While belief in natural causes is more common, belief in supernatural causes persists despite modernizing and

  18. Causal conditionals and counterfactuals

    PubMed Central

    Frosch, Caren A.; Byrne, Ruth M.J.

    2012-01-01

    Causal counterfactuals e.g., ‘if the ignition key had been turned then the car would have started’ and causal conditionals e.g., ‘if the ignition key was turned then the car started’ are understood by thinking about multiple possibilities of different sorts, as shown in six experiments using converging evidence from three different types of measures. Experiments 1a and 1b showed that conditionals that comprise enabling causes, e.g., ‘if the ignition key was turned then the car started’ primed people to read quickly conjunctions referring to the possibility of the enabler occurring without the outcome, e.g., ‘the ignition key was turned and the car did not start’. Experiments 2a and 2b showed that people paraphrased causal conditionals by using causal or temporal connectives (because, when), whereas they paraphrased causal counterfactuals by using subjunctive constructions (had…would have). Experiments 3a and 3b showed that people made different inferences from counterfactuals presented with enabling conditions compared to none. The implications of the results for alternative theories of conditionals are discussed. PMID:22858874

  19. Causality discovery technology

    NASA Astrophysics Data System (ADS)

    Chen, M.; Ertl, T.; Jirotka, M.; Trefethen, A.; Schmidt, A.; Coecke, B.; Bañares-Alcántara, R.

    2012-11-01

    Causality is the fabric of our dynamic world. We all make frequent attempts to reason causation relationships of everyday events (e.g., what was the cause of my headache, or what has upset Alice?). We attempt to manage causality all the time through planning and scheduling. The greatest scientific discoveries are usually about causality (e.g., Newton found the cause for an apple to fall, and Darwin discovered natural selection). Meanwhile, we continue to seek a comprehensive understanding about the causes of numerous complex phenomena, such as social divisions, economic crisis, global warming, home-grown terrorism, etc. Humans analyse and reason causality based on observation, experimentation and acquired a priori knowledge. Today's technologies enable us to make observations and carry out experiments in an unprecedented scale that has created data mountains everywhere. Whereas there are exciting opportunities to discover new causation relationships, there are also unparalleled challenges to benefit from such data mountains. In this article, we present a case for developing a new piece of ICT, called Causality Discovery Technology. We reason about the necessity, feasibility and potential impact of such a technology.

  20. Causal networks or causal islands? The representation of mechanisms and the transitivity of causal judgment

    PubMed Central

    Johnson, Samuel G. B.; Ahn, Woo-kyoung

    2014-01-01

    Knowledge of mechanisms is critical for causal reasoning. We contrasted two possible organizations of causal knowledge—an interconnected causal network, where events are causally connected without any boundaries delineating discrete mechanisms; or a set of disparate mechanisms—causal islands—such that events in different mechanisms are not thought to be related even when they belong to the same causal chain. To distinguish these possibilities, we used causal transitivity—the inference given A causes B and B causes C that A causes C. Specifically, causal chains schematized as one chunk or mechanism in semantic memory (e.g., exercising, becoming thirsty, drinking water) led to transitive causal judgments. On the other hand, chains schematized as multiple chunks (e.g., having sex, becoming pregnant, becoming nauseous) led to intransitive judgments despite strong intermediate links (Experiments 1–3). Normative accounts of causal intransitivity could not explain these intransitive judgments (Experiments 4–5). PMID:25556901

  1. Causal premise semantics.

    PubMed

    Kaufmann, Stefan

    2013-08-01

    The rise of causality and the attendant graph-theoretic modeling tools in the study of counterfactual reasoning has had resounding effects in many areas of cognitive science, but it has thus far not permeated the mainstream in linguistic theory to a comparable degree. In this study I show that a version of the predominant framework for the formal semantic analysis of conditionals, Kratzer-style premise semantics, allows for a straightforward implementation of the crucial ideas and insights of Pearl-style causal networks. I spell out the details of such an implementation, focusing especially on the notions of intervention on a network and backtracking interpretations of counterfactuals.

  2. The Perceived Socioeconomic Status Is an Important Factor of Health Recovery for Victims of Occupational Accidents in Korea

    PubMed Central

    Roh, Jaehoon

    2016-01-01

    We aimed to examine whether there is a correlation between the health recovery of industrial accident victims and their perceived socioeconomic status. Data were obtained from the first Panel Study of Worker's Compensation Insurance, which included 2,000 participants. We performed multivariate regression analysis and determined the odds ratios for participants with a subjectively lower socioeconomic status and for those with a subjectively lower middle socioeconomic status using 95% confidence intervals. An additional multivariate regression analysis yielded the odds ratios for participants with a subjectively lower socioeconomic status and those with a subjectively upper middle socioeconomic class using 95% confidence intervals. Of all participants, 299 reported a full recovery, whereas 1,701 did not. We examined the odds ratio (95% confidence intervals) for participants' health recovery according to their subjective socioeconomic status while controlling for sex, age, education, tobacco use, alcohol use, subjective state of health prior to the accident, chronic disease, employment duration, recovery period, accident type, disability status, disability rating, and economic participation. The odds of recovery in participants with a subjectively lower middle socioeconomic status were 1.707 times greater (1.264-2.305) than that of those with a subjectively lower socioeconomic status. Similarly, the odds of recovery in participants with a subjectively upper middle socioeconomic status were 3.124 times greater (1.795-5.438) than that of those with a subjectively lower socioeconomic status. Our findings indicate that participants' perceived socioeconomic disparities extend to disparities in their health status. The reinforcement of welfare measures is greatly needed to temper these disparities. PMID:26839467

  3. The Perceived Socioeconomic Status Is an Important Factor of Health Recovery for Victims of Occupational Accidents in Korea.

    PubMed

    Seok, Hongdeok; Yoon, Jin-Ha; Lee, Wanhyung; Lee, June-Hee; Jung, Pil Kyun; Roh, Jaehoon; Won, Jong-Uk

    2016-02-01

    We aimed to examine whether there is a correlation between the health recovery of industrial accident victims and their perceived socioeconomic status. Data were obtained from the first Panel Study of Worker's Compensation Insurance, which included 2,000 participants. We performed multivariate regression analysis and determined the odds ratios for participants with a subjectively lower socioeconomic status and for those with a subjectively lower middle socioeconomic status using 95% confidence intervals. An additional multivariate regression analysis yielded the odds ratios for participants with a subjectively lower socioeconomic status and those with a subjectively upper middle socioeconomic class using 95% confidence intervals. Of all participants, 299 reported a full recovery, whereas 1,701 did not. We examined the odds ratio (95% confidence intervals) for participants' health recovery according to their subjective socioeconomic status while controlling for sex, age, education, tobacco use, alcohol use, subjective state of health prior to the accident, chronic disease, employment duration, recovery period, accident type, disability status, disability rating, and economic participation. The odds of recovery in participants with a subjectively lower middle socioeconomic status were 1.707 times greater (1.264-2.305) than that of those with a subjectively lower socioeconomic status. Similarly, the odds of recovery in participants with a subjectively upper middle socioeconomic status were 3.124 times greater (1.795-5.438) than that of those with a subjectively lower socioeconomic status. Our findings indicate that participants' perceived socioeconomic disparities extend to disparities in their health status. The reinforcement of welfare measures is greatly needed to temper these disparities. PMID:26839467

  4. Evaluating Causal Models.

    ERIC Educational Resources Information Center

    Watt, James H., Jr.

    Pointing out that linear causal models can organize the interrelationships of a large number of variables, this paper contends that such models are particularly useful to mass communication research, which must by necessity deal with complex systems of variables. The paper first outlines briefly the philosophical requirements for establishing a…

  5. Causal Responsibility and Counterfactuals

    ERIC Educational Resources Information Center

    Lagnado, David A.; Gerstenberg, Tobias; Zultan, Ro'i

    2013-01-01

    How do people attribute responsibility in situations where the contributions of multiple agents combine to produce a joint outcome? The prevalence of over-determination in such cases makes this a difficult problem for counterfactual theories of causal responsibility. In this article, we explore a general framework for assigning responsibility in…

  6. Causal Premise Semantics

    ERIC Educational Resources Information Center

    Kaufmann, Stefan

    2013-01-01

    The rise of causality and the attendant graph-theoretic modeling tools in the study of counterfactual reasoning has had resounding effects in many areas of cognitive science, but it has thus far not permeated the mainstream in linguistic theory to a comparable degree. In this study I show that a version of the predominant framework for the formal…

  7. Causal essentialism in kinds.

    PubMed

    Ahn, Woo-kyoung; Taylor, Eric G; Kato, Daniel; Marsh, Jessecae K; Bloom, Paul

    2013-06-01

    The current study examines causal essentialism, derived from psychological essentialism of concepts. We examine whether people believe that members of a category share some underlying essence that is both necessary and sufficient for category membership and that also causes surface features. The main claim is that causal essentialism is restricted to categories that correspond to our intuitive notions of existing kinds and hence is more attenuated for categories that are based on arbitrary criteria. Experiments 1 and 3 found that people overtly endorse causal essences in nonarbitrary kinds but are less likely to do so for arbitrary categories. Experiments 2 and 4 found that people were more willing to generalize a member's known causal relations (or lack thereof) when dealing with a kind than when dealing with an arbitrary category. These differences between kinds and arbitrary categories were found across various domains-not only for categories of living things, but also for artefacts. These findings have certain real-world implications, including how people make sense of mental disorders that are treated as real kinds. PMID:23098315

  8. The Causal Asymmetry

    ERIC Educational Resources Information Center

    White, Peter A.

    2006-01-01

    It is hypothesized that there is a pervasive and fundamental bias in humans' understanding of physical causation: Once the roles of cause and effect are assigned to objects in interactions, people tend to overestimate the strength and importance of the causal object and underestimate that of the effect object in bringing about the outcome. This…

  9. Causality: Physics and Philosophy

    ERIC Educational Resources Information Center

    Chatterjee, Atanu

    2013-01-01

    Nature is a complex causal network exhibiting diverse forms and species. These forms or rather systems are physically open, structurally complex and naturally adaptive. They interact with the surrounding media by operating a positive-feedback loop through which, they adapt, organize and self-organize themselves in response to the ever-changing…

  10. Transfer factors and effective half-lives of (134)Cs and (137)Cs in different environmental sample types obtained from Northern Finland: case Fukushima accident.

    PubMed

    Koivurova, Matias; Leppänen, Ari-Pekka; Kallio, Antti

    2015-08-01

    The Fukushima NPP accident caused a small but detectable cesium fallout in northern Finland, of the order of 1 Bq/m(2). This fallout transferred further to soil, water, flora and fauna. By using modern HPGe detector systems traces of (134)Cs from the Fukushima fallout were observed in various samples of biota. In northern Finland different types of environmental samples such as reindeer meat, berries, fish, lichens and wolf were collected during 2011-2013. The observed (134)Cs concentrations varied from 0.1 Bq/kg to a few Bq/kg. By using the known (134)Cs/(137)Cs ratio observed in Fukushima fallout the increase of the Fukushima accident to the (137)Cs concentrations was found to vary from 0.06 % to 6.9 % depending on the sample type. The aggregated transfer factors (Tag) and effective half-lives (Teff) for (134)Cs and (137)Cs were also determined and then compared with known values found from earlier studies which are calculated based on the fallout from the Chernobyl accident. Generally, the Tag and Teff values determined in this study were found to agree with the values found in the earlier studies. The Teff values were sample-type specific and were found to vary from 0.91 to 2.1 years for (134)Cs and the estimates for (137)Cs ranged between 1.6 and 19 years. Interestingly, the ground lichens had the longest Teff whereas the beard lichen had the shortest. In fauna, highest Tag values were determined for wolf meat ranging between 1.0 and 2.2 m(2)/kg. In flora, the highest Tag values were determined for beard lichens, ranging from 1.9 m(2)/kg to 3.5 m(2)/kg.

  11. Transfer factors and effective half-lives of (134)Cs and (137)Cs in different environmental sample types obtained from Northern Finland: case Fukushima accident.

    PubMed

    Koivurova, Matias; Leppänen, Ari-Pekka; Kallio, Antti

    2015-08-01

    The Fukushima NPP accident caused a small but detectable cesium fallout in northern Finland, of the order of 1 Bq/m(2). This fallout transferred further to soil, water, flora and fauna. By using modern HPGe detector systems traces of (134)Cs from the Fukushima fallout were observed in various samples of biota. In northern Finland different types of environmental samples such as reindeer meat, berries, fish, lichens and wolf were collected during 2011-2013. The observed (134)Cs concentrations varied from 0.1 Bq/kg to a few Bq/kg. By using the known (134)Cs/(137)Cs ratio observed in Fukushima fallout the increase of the Fukushima accident to the (137)Cs concentrations was found to vary from 0.06 % to 6.9 % depending on the sample type. The aggregated transfer factors (Tag) and effective half-lives (Teff) for (134)Cs and (137)Cs were also determined and then compared with known values found from earlier studies which are calculated based on the fallout from the Chernobyl accident. Generally, the Tag and Teff values determined in this study were found to agree with the values found in the earlier studies. The Teff values were sample-type specific and were found to vary from 0.91 to 2.1 years for (134)Cs and the estimates for (137)Cs ranged between 1.6 and 19 years. Interestingly, the ground lichens had the longest Teff whereas the beard lichen had the shortest. In fauna, highest Tag values were determined for wolf meat ranging between 1.0 and 2.2 m(2)/kg. In flora, the highest Tag values were determined for beard lichens, ranging from 1.9 m(2)/kg to 3.5 m(2)/kg. PMID:25935505

  12. Causal Discovery of Dynamic Systems

    ERIC Educational Resources Information Center

    Voortman, Mark

    2010-01-01

    Recently, several philosophical and computational approaches to causality have used an interventionist framework to clarify the concept of causality [Spirtes et al., 2000, Pearl, 2000, Woodward, 2005]. The characteristic feature of the interventionist approach is that causal models are potentially useful in predicting the effects of manipulations.…

  13. Context, causality, and appreciation.

    PubMed

    Ross, Stephanie

    2013-04-01

    I applaud and elaborate on the contextualism at the heart of Bullot & Reber's (B&R's) theory, challenge two aspects of the appreciative structure they posit (the causal reasoning that allegedly underlies the design stance and the segregation of the component stages), suggest that expert and novice appreciators operate differently, and question the degree to which B&R's final theory is open to empirical investigation. PMID:23507111

  14. Context, causality, and appreciation.

    PubMed

    Ross, Stephanie

    2013-04-01

    I applaud and elaborate on the contextualism at the heart of Bullot & Reber's (B&R's) theory, challenge two aspects of the appreciative structure they posit (the causal reasoning that allegedly underlies the design stance and the segregation of the component stages), suggest that expert and novice appreciators operate differently, and question the degree to which B&R's final theory is open to empirical investigation.

  15. Causal Responsibility and Counterfactuals

    PubMed Central

    Lagnado, David A; Gerstenberg, Tobias; Zultan, Ro'i

    2013-01-01

    How do people attribute responsibility in situations where the contributions of multiple agents combine to produce a joint outcome? The prevalence of over-determination in such cases makes this a difficult problem for counterfactual theories of causal responsibility. In this article, we explore a general framework for assigning responsibility in multiple agent contexts. We draw on the structural model account of actual causation (e.g., Halpern & Pearl, 2005) and its extension to responsibility judgments (Chockler & Halpern, 2004). We review the main theoretical and empirical issues that arise from this literature and propose a novel model of intuitive judgments of responsibility. This model is a function of both pivotality (whether an agent made a difference to the outcome) and criticality (how important the agent is perceived to be for the outcome, before any actions are taken). The model explains empirical results from previous studies and is supported by a new experiment that manipulates both pivotality and criticality. We also discuss possible extensions of this model to deal with a broader range of causal situations. Overall, our approach emphasizes the close interrelations between causality, counterfactuals, and responsibility attributions. PMID:23855451

  16. Optimization of health protection of the public following a major nuclear accident: Interaction between radiation protection and social and psychological factors

    SciTech Connect

    Allen, P.T.; Archangelskaya, G.V.; Ramsaev, P.V.

    1996-11-01

    National and international guidance on the optimization of countermeasures to reduce doses in the post-release phase of an accident rightly emphasizes the importance and relevance of psychological, social, and economic factors to this process (e.g., NRPB 1990; ICRP 1991: CEC 1993; IAEA 1994). However, whilst economic factors are, at least partially, taken into account in developing the advice, explicit guidance is not provided on how psychological and social factors should be included in the optimization. Instead it is suggested that this is a matter for those with the appropriate competence and those with responsibility for making the final decisions. This approach implicitly assumes that the optimization of psychological and social factors, and that the results of the two procedures can then be combined to arrive at an optimum course of action. We recognize that formal optimization only forms one input to the process of making decisions on countermeasures and that it is important that psychological and social factors, as well as any other factors, are not {open_quotes}double-counted.{close_quotes} i.e., accounted for within international advice and then again at the time of the decision. It is our view that the optimization of radiation protection and economic factors, and certain psychological and social factors, should not be carried out independently. Research conducted by our respective organization indicates a number of areas in which the optimization of radiation protection and economic factors requires an understanding of key psychological and social processes. These areas fall into three groups; the need to ensure that countermeasures are successfully implemented, the need to achieve a net benefit for overall health, and the need to ensure a smooth transition back to normal living. 10 refs.

  17. Radiation accidents

    SciTech Connect

    Saenger, E.L.

    1986-09-01

    It is essential that emergency physicians understand ways to manage patients contaminated by radioactive materials and/or exposed to external radiation sources. Contamination accidents require careful surveys to identify the metabolic pathway of the radionuclides to guide prognosis and treatment. The level of treatment required will depend on careful surveys and meticulous decontamination. There is no specific therapy for the acute radiation syndrome. Prophylactic antibodies are desirable. For severely exposed patients treatment is similar to the supportive care given to patients undergoing organ transplantation. For high-dose extremity injury, no methods have been developed to reverse the fibrosing endarteritis that eventually leads to tissue death so frequently found with this type of injury. Although the Three Mile Island episode of March 1979 created tremendous public concern, there were no radiation injuries. The contamination outside the reactor building and the release of radioiodine were negligible. The accidental fuel element meltdown at Chernobyl, USSR, resulted in many cases of acute radiation syndrome. More than 100,000 people were exposed to high levels of radioactive fallout. The general principles outlined here are applicable to accidents of that degree of severity.

  18. Radiation accidents.

    PubMed

    Saenger, E L

    1986-09-01

    It is essential that emergency physicians understand ways to manage patients contaminated by radioactive materials and/or exposed to external radiation sources. Contamination accidents require careful surveys to identify the metabolic pathway of the radionuclides to guide prognosis and treatment. The level of treatment required will depend on careful surveys and meticulous decontamination. There is no specific therapy for the acute radiation syndrome. Prophylactic antibodies are desirable. For severely exposed patients treatment is similar to the supportive care given to patients undergoing organ transplantation. For high-dose extremity injury, no methods have been developed to reverse the fibrosing endarteritis that eventually leads to tissue death so frequently found with this type of injury. Although the Three Mile Island episode of March 1979 created tremendous public concern, there were no radiation injuries. The contamination outside the reactor building and the release of radioiodine were negligible. The accidental fuel element meltdown at Chernobyl, USSR, resulted in many cases of acute radiation syndrome. More than 100,000 people were exposed to high levels of radioactive fallout. The general principles outlined here are applicable to accidents of that degree of severity. PMID:3526994

  19. Reducing Aviation Weather-Related Accidents Through High-Fidelity Weather Information Distribution and Presentation

    NASA Technical Reports Server (NTRS)

    Stough, H. Paul, III; Shafer, Daniel B.; Schaffner, Philip R.; Martzaklis, Konstantinos S.

    2000-01-01

    In February 1997, the US President announced a national goal to reduce the fatal accident rate for aviation by 80% within ten years. The National Aeronautics and Space Administration established the Aviation Safety Program to develop technologies needed to meet this aggressive goal. Because weather has been identified (is a causal factor in approximately 30% of all aviation accidents, a project was established for the development of technologies that will provide accurate, time and intuitive information to pilots, dispatchers, and air traffic controllers to enable the detection and avoidance of atmospheric hazards. This project addresses the weather information needs of general, corporate, regional, and transport aircraft operators. An overview and status of research and development efforts for high-fidelity weather information distribution and presentation is discussed with emphasis on weather information in the cockpit.

  20. Radiation and non-radiation factors and their impact on the natural history of coronary heart disease in Chornobyl accident clean-up workers.

    PubMed

    Bilyi, D O; Nastina, O M; Gabulavichene, Zh M; Sydorenko, G V; Bazyka, O D; Bilaya, V V; Kovalyov, O S

    2014-09-01

    The objective of the study was to evaluate the impact of a range of risk factors and ionizing radiation on the severity of clinical presentation of coronary heart disease (CHD) in Chornobyl accident clean-up workers (ACW). Materials and methods. A total of 376 ACW and 123 Kiev city residents with no exposure to radiation participated in the study. Study scope included the case history recording, clinical check-up, electrocardiography (ECG), daily ECG-monitoring, daily arterial blood pressure monitoring, exercise ECG, Doppler ultrasound (Doppler echocardiography), and serum lipid profile assay. The severity of CHD was scored as a sum of functional class (FC) of angina pectoris and stage of heart failure (HF) to estimate the combined impact of several risk factors. Participation in the clean-up work, age, gender, body mass excess, hypercholesterolemia, CHD, diabetes mellitus (DM), survived myocardial infarction (MI) and acute cerebral stroke, heart rhythm abnormalities, and a complete bundle branch block were accounted as risk factors. Both separate and combined impact of those factors was assayed. The combined effect was scored as a sum where value zero corresponded to no sign and value one corresponded to its presence, whereas values from 1 to 4 explained the expression of a sign according to severity or stage of a disease according to contemporary classifications. Results and conclusions. Despite the fact that clinical characterization, functional state of cardiovascular system, and comorbidities in ACW were almost similar to that in control group the onset of CHD in ACW was significantly earlier (55.9 vs. 59.8 years old). According to Spearman's rank-order correlation data there was a reliable link of FC grades and HF severity values sum to the sum of indices scoring the age group of patients, their gender, presence of arterial hypertension, MI in a history, DM type 2, heart rhythm abnormalities, and a complete bundle branch block. Cluster of risk factors

  1. Radiation and non-radiation factors and their impact on the natural history of coronary heart disease in Chornobyl accident clean-up workers.

    PubMed

    Bilyi, D O; Nastina, O M; Gabulavichene, Zh M; Sydorenko, G V; Bazyka, O D; Bilaya, V V; Kovalyov, O S

    2014-09-01

    The objective of the study was to evaluate the impact of a range of risk factors and ionizing radiation on the severity of clinical presentation of coronary heart disease (CHD) in Chornobyl accident clean-up workers (ACW). Materials and methods. A total of 376 ACW and 123 Kiev city residents with no exposure to radiation participated in the study. Study scope included the case history recording, clinical check-up, electrocardiography (ECG), daily ECG-monitoring, daily arterial blood pressure monitoring, exercise ECG, Doppler ultrasound (Doppler echocardiography), and serum lipid profile assay. The severity of CHD was scored as a sum of functional class (FC) of angina pectoris and stage of heart failure (HF) to estimate the combined impact of several risk factors. Participation in the clean-up work, age, gender, body mass excess, hypercholesterolemia, CHD, diabetes mellitus (DM), survived myocardial infarction (MI) and acute cerebral stroke, heart rhythm abnormalities, and a complete bundle branch block were accounted as risk factors. Both separate and combined impact of those factors was assayed. The combined effect was scored as a sum where value zero corresponded to no sign and value one corresponded to its presence, whereas values from 1 to 4 explained the expression of a sign according to severity or stage of a disease according to contemporary classifications. Results and conclusions. Despite the fact that clinical characterization, functional state of cardiovascular system, and comorbidities in ACW were almost similar to that in control group the onset of CHD in ACW was significantly earlier (55.9 vs. 59.8 years old). According to Spearman's rank-order correlation data there was a reliable link of FC grades and HF severity values sum to the sum of indices scoring the age group of patients, their gender, presence of arterial hypertension, MI in a history, DM type 2, heart rhythm abnormalities, and a complete bundle branch block. Cluster of risk factors

  2. [FROM STATISTICAL ASSOCIATIONS TO SCIENTIFIC CAUSALITY].

    PubMed

    Golan, Daniel; Linn, Shay

    2015-06-01

    The pathogenesis of most chronic diseases is complex and probably involves the interaction of multiple genetic and environmental risk factors. One way to learn about disease triggers is from statistically significant associations in epidemiological studies. However, associations do not necessarily prove causation. Associations can commonly result from bias, confounding and reverse causation. Several paradigms for causality inference have been developed. Henle-Koch postulates are mainly applied for infectious diseases. Austin Bradford Hill's criteria may serve as a practical tool to weigh the evidence regarding the probability that a single new risk factor for a given disease is indeed causal. These criteria are irrelevant for estimating the causal relationship between exposure to a risk factor and disease whenever biological causality has been previously established. Thus, it is highly probable that past exposure of an individual to definite carcinogens is related to his cancer, even without proving an association between this exposure and cancer in his group. For multifactorial diseases, Rothman's model of interacting sets of component causes can be applied.

  3. [Drowning accidents in childhood].

    PubMed

    Krandick, G; Mantel, K

    1990-09-30

    This is a report on five boys aged between 1 and 5 years who, after prolonged submersion in cold water, were treated at our department. On being taken out of the water, all the patients were clinically dead. After 1- to 3-hour successful cardiopulmonary resuscitation, with a rectal temperature of about 27 degrees C, they were rewarmed at a rate of 1 degree/hour. Two patients died within a few hours after the accident. One patient survived with an apallic syndrome, 2 children survived with no sequelae. In the event of a water-related accident associated with hypothermia, we consider suitable resuscitation to have preference over rewarming measures. The most important treatment guidelines and prognostic factors are discussed.

  4. Causal Entropic Forces

    NASA Astrophysics Data System (ADS)

    Wissner-Gross, A. D.; Freer, C. E.

    2013-04-01

    Recent advances in fields ranging from cosmology to computer science have hinted at a possible deep connection between intelligence and entropy maximization, but no formal physical relationship between them has yet been established. Here, we explicitly propose a first step toward such a relationship in the form of a causal generalization of entropic forces that we find can cause two defining behaviors of the human “cognitive niche”—tool use and social cooperation—to spontaneously emerge in simple physical systems. Our results suggest a potentially general thermodynamic model of adaptive behavior as a nonequilibrium process in open systems.

  5. Quantum information causality.

    PubMed

    Pitalúa-García, Damián

    2013-05-24

    How much information can a transmitted physical system fundamentally communicate? We introduce the principle of quantum information causality, which states the maximum amount of quantum information that a quantum system can communicate as a function of its dimension, independently of any previously shared quantum physical resources. We present a new quantum information task, whose success probability is upper bounded by the new principle, and show that an optimal strategy to perform it combines the quantum teleportation and superdense coding protocols with a task that has classical inputs. PMID:23745844

  6. Fast causal multicast

    NASA Technical Reports Server (NTRS)

    Birman, Kenneth P.; Schiper, Andre; Stephenson, Pat

    1990-01-01

    A new protocol is presented that efficiently implements a reliable, causally ordered multicast primitive and is easily extended into a totally ordered one. Intended for use in the ISIS toolkit, it offers a way to bypass the most costly aspects of ISIS while benefiting from virtual synchrony. The facility scales with bounded overhead. Measured speedups of more than an order of magnitude were obtained when the protocol was implemented within ISIS. One conclusion is that systems such as ISIS can achieve performance competitive with the best existing multicast facilities - a finding contradicting the widespread concern that fault-tolerance may be unacceptably costly.

  7. Individual differences in causal uncertainty.

    PubMed

    Weary, G; Edwards, J A

    1994-08-01

    This article presents a scale that measures chronic individual differences in people's uncertainty about their ability to understand and detect cause-and-effect relationships in the social world: the Causal Uncertainty Scale (CUS). The results of Study 1 indicated that the scale has good internal and adequate test-retest reliability. Additionally, the results of a factor analysis suggested that the scale appears to be tapping a single construct. Study 2 examined the convergent and discriminant validity of the scale, and Studies 3 and 4 examined the predictive and incremental validity of the scale. The importance of the CUS to work on depressives' social information processing and for basic research and theory on human social judgment processes is discussed.

  8. Learning a theory of causality.

    PubMed

    Goodman, Noah D; Ullman, Tomer D; Tenenbaum, Joshua B

    2011-01-01

    The very early appearance of abstract knowledge is often taken as evidence for innateness. We explore the relative learning speeds of abstract and specific knowledge within a Bayesian framework and the role for innate structure. We focus on knowledge about causality, seen as a domain-general intuitive theory, and ask whether this knowledge can be learned from co-occurrence of events. We begin by phrasing the causal Bayes nets theory of causality and a range of alternatives in a logical language for relational theories. This allows us to explore simultaneous inductive learning of an abstract theory of causality and a causal model for each of several causal systems. We find that the correct theory of causality can be learned relatively quickly, often becoming available before specific causal theories have been learned--an effect we term the blessing of abstraction. We then explore the effect of providing a variety of auxiliary evidence and find that a collection of simple perceptual input analyzers can help to bootstrap abstract knowledge. Together, these results suggest that the most efficient route to causal knowledge may be to build in not an abstract notion of causality but a powerful inductive learning mechanism and a variety of perceptual supports. While these results are purely computational, they have implications for cognitive development, which we explore in the conclusion.

  9. Photodetection and causality I

    NASA Astrophysics Data System (ADS)

    de Haan, M.

    1985-09-01

    We investigate in this paper the link between the measurement process in quantum mechanics and casuality associated to a finite velocity of field propagation. We use models of interaction of a bound state with a scalar field. We first show that in the existing approaches, time delays resulting from the finite velocity of propagation have been obtained only as a consequence of ad hoc approximations. We show that exact causality can be restored in the case of a single photodetection by a slight change of the observable associated to the measurement process. Moreover, this modification may be justified by the introduction of a simple model for the photodetector. We present qualitative arguments to show that this procedure cannot be extended to the case of multiple photodetections. The process of repeated photodetection clashes therefore with causality. This paradox is closely related to the Zeno paradox described by Misra and Sudarshan 1). Both may be traced back to the positive definite character of the hamiltonian which is the generator of motion in quantum mechanics.

  10. Experimental test of nonlocal causality

    PubMed Central

    Ringbauer, Martin; Giarmatzi, Christina; Chaves, Rafael; Costa, Fabio; White, Andrew G.; Fedrizzi, Alessandro

    2016-01-01

    Explaining observations in terms of causes and effects is central to empirical science. However, correlations between entangled quantum particles seem to defy such an explanation. This implies that some of the fundamental assumptions of causal explanations have to give way. We consider a relaxation of one of these assumptions, Bell’s local causality, by allowing outcome dependence: a direct causal influence between the outcomes of measurements of remote parties. We use interventional data from a photonic experiment to bound the strength of this causal influence in a two-party Bell scenario, and observational data from a Bell-type inequality test for the considered models. Our results demonstrate the incompatibility of quantum mechanics with a broad class of nonlocal causal models, which includes Bell-local models as a special case. Recovering a classical causal picture of quantum correlations thus requires an even more radical modification of our classical notion of cause and effect. PMID:27532045

  11. Redundant variables and Granger causality

    NASA Astrophysics Data System (ADS)

    Angelini, L.; de Tommaso, M.; Marinazzo, D.; Nitti, L.; Pellicoro, M.; Stramaglia, S.

    2010-03-01

    We discuss the use of multivariate Granger causality in presence of redundant variables: the application of the standard analysis, in this case, leads to under estimation of causalities. Using the un-normalized version of the causality index, we quantitatively develop the notions of redundancy and synergy in the frame of causality and propose two approaches to group redundant variables: (i) for a given target, the remaining variables are grouped so as to maximize the total causality and (ii) the whole set of variables is partitioned to maximize the sum of the causalities between subsets. We show the application to a real neurological experiment, aiming to a deeper understanding of the physiological basis of abnormal neuronal oscillations in the migraine brain. The outcome by our approach reveals the change in the informational pattern due to repetitive transcranial magnetic stimulations.

  12. Experimental test of nonlocal causality.

    PubMed

    Ringbauer, Martin; Giarmatzi, Christina; Chaves, Rafael; Costa, Fabio; White, Andrew G; Fedrizzi, Alessandro

    2016-08-01

    Explaining observations in terms of causes and effects is central to empirical science. However, correlations between entangled quantum particles seem to defy such an explanation. This implies that some of the fundamental assumptions of causal explanations have to give way. We consider a relaxation of one of these assumptions, Bell's local causality, by allowing outcome dependence: a direct causal influence between the outcomes of measurements of remote parties. We use interventional data from a photonic experiment to bound the strength of this causal influence in a two-party Bell scenario, and observational data from a Bell-type inequality test for the considered models. Our results demonstrate the incompatibility of quantum mechanics with a broad class of nonlocal causal models, which includes Bell-local models as a special case. Recovering a classical causal picture of quantum correlations thus requires an even more radical modification of our classical notion of cause and effect. PMID:27532045

  13. Experimental test of nonlocal causality.

    PubMed

    Ringbauer, Martin; Giarmatzi, Christina; Chaves, Rafael; Costa, Fabio; White, Andrew G; Fedrizzi, Alessandro

    2016-08-01

    Explaining observations in terms of causes and effects is central to empirical science. However, correlations between entangled quantum particles seem to defy such an explanation. This implies that some of the fundamental assumptions of causal explanations have to give way. We consider a relaxation of one of these assumptions, Bell's local causality, by allowing outcome dependence: a direct causal influence between the outcomes of measurements of remote parties. We use interventional data from a photonic experiment to bound the strength of this causal influence in a two-party Bell scenario, and observational data from a Bell-type inequality test for the considered models. Our results demonstrate the incompatibility of quantum mechanics with a broad class of nonlocal causal models, which includes Bell-local models as a special case. Recovering a classical causal picture of quantum correlations thus requires an even more radical modification of our classical notion of cause and effect.

  14. Redundant variables and Granger causality.

    PubMed

    Angelini, L; de Tommaso, M; Marinazzo, D; Nitti, L; Pellicoro, M; Stramaglia, S

    2010-03-01

    We discuss the use of multivariate Granger causality in presence of redundant variables: the application of the standard analysis, in this case, leads to under estimation of causalities. Using the un-normalized version of the causality index, we quantitatively develop the notions of redundancy and synergy in the frame of causality and propose two approaches to group redundant variables: (i) for a given target, the remaining variables are grouped so as to maximize the total causality and (ii) the whole set of variables is partitioned to maximize the sum of the causalities between subsets. We show the application to a real neurological experiment, aiming to a deeper understanding of the physiological basis of abnormal neuronal oscillations in the migraine brain. The outcome by our approach reveals the change in the informational pattern due to repetitive transcranial magnetic stimulations.

  15. Causal inference based on counterfactuals

    PubMed Central

    Höfler, M

    2005-01-01

    Background The counterfactual or potential outcome model has become increasingly standard for causal inference in epidemiological and medical studies. Discussion This paper provides an overview on the counterfactual and related approaches. A variety of conceptual as well as practical issues when estimating causal effects are reviewed. These include causal interactions, imperfect experiments, adjustment for confounding, time-varying exposures, competing risks and the probability of causation. It is argued that the counterfactual model of causal effects captures the main aspects of causality in health sciences and relates to many statistical procedures. Summary Counterfactuals are the basis of causal inference in medicine and epidemiology. Nevertheless, the estimation of counterfactual differences pose several difficulties, primarily in observational studies. These problems, however, reflect fundamental barriers only when learning from observations, and this does not invalidate the counterfactual concept. PMID:16159397

  16. Blaming Leaders for Organizational Accidents: Proxy Logic in Collective- versus Individual-Agency Cultures

    ERIC Educational Resources Information Center

    Zemba, Yuriko; Young, Maia J.; Morris, Michael W.

    2006-01-01

    The current research investigates whether observers blame leaders for organizational accidents even when these managers are known to be causally uninvolved. Past research finds that the public blames managers for organizational harm if the managers are perceived to have personally played a causal role. The present research argues that East Asian…

  17. Retrospective self-reports of childhood accidents causing unconsciousness in phallometrically diagnosed pedophiles.

    PubMed

    Blanchard, Ray; Christensen, Bruce K; Strong, Scott M; Cantor, James M; Kuban, Michael E; Klassen, Philip; Dickey, Robert; Blak, Thomas

    2002-12-01

    The present study investigated whetherhead injuries in childhood might increase the risk of pedophilia in males. The subjects were 1206 patients referred to a clinical sexology service for assessment of their erotic preferences. These were classified, on the basis of phallometric test results, as pedophilic (n = 413) or nonpedophilic (n = 793). Information regarding early head injuries, other signs of possible neurodevelopmental problems, and parental histories of psychiatric treatment were collected with self-administered questionnaires. The results showed that childhood accidents that resulted in unconsciousness were associated with pedophilia and with lower levels of intelligence and education. These associations were statistically significant for accidents that occurred before the age of 6, but not for accidents that occurred between the ages of 6 and 12. These results are compatible with the hypothesis that neurodevelopmental perturbations in early childhood may increase the risk of pedophilia. They are also, however, compatible with the alternative explanation that prior neurodevelopmental problems lead to accident-proneness and head injury, on the one hand, and to pedophilia, on the other, and that head injury has no causal influence on pedophilia. A secondary finding was that the pedophiles were more likely to report that their mothers had undergone psychiatric treatment. This finding suggests that pedophilia may be influenced by genetic factors, which are manifested in women as an increased risk of psychiatric problems, and in their sons, as an increased risk of erotic interest in children. PMID:12462478

  18. An Examination of Commercial Aviation Accidents and Incidents Related to Integrated Vehicle Health Management

    NASA Technical Reports Server (NTRS)

    Reveley, Mary S.; Briggs, Jeffrey L.; Thomas, Megan A.; Evans, Joni K.; Jones, Sharon M.

    2011-01-01

    The Integrated Vehicle Health Management (IVHM) Project is one of the four projects within the National Aeronautics and Space Administration's (NASA) Aviation Safety Program (AvSafe). The IVHM Project conducts research to develop validated tools and technologies for automated detection, diagnosis, and prognosis that enable mitigation of adverse events during flight. Adverse events include those that arise from system, subsystem, or component failure, faults, and malfunctions due to damage, degradation, or environmental hazards that occur during flight. Determining the causal factors and adverse events related to IVHM technologies will help in the formulation of research requirements and establish a list of example adverse conditions against which IVHM technologies can be evaluated. This paper documents the results of an examination of the most recent statistical/prognostic accident and incident data that is available from the Aviation Safety Information Analysis and Sharing (ASIAS) System to determine the causal factors of system/component failures and/or malfunctions in U.S. commercial aviation accidents and incidents.

  19. Preliminary Analysis of Aircraft Loss of Control Accidents: Worst Case Precursor Combinations and Temporal Sequencing

    NASA Technical Reports Server (NTRS)

    Belcastro, Christine M.; Groff, Loren; Newman, Richard L.; Foster, John V.; Crider, Dennis H.; Klyde, David H.; Huston, A. McCall

    2014-01-01

    Aircraft loss of control (LOC) is a leading cause of fatal accidents across all transport airplane and operational classes, and can result from a wide spectrum of hazards, often occurring in combination. Technologies developed for LOC prevention and recovery must therefore be effective under a wide variety of conditions and uncertainties, including multiple hazards, and their validation must provide a means of assessing system effectiveness and coverage of these hazards. This requires the definition of a comprehensive set of LOC test scenarios based on accident and incident data as well as future risks. This paper defines a comprehensive set of accidents and incidents over a recent 15 year period, and presents preliminary analysis results to identify worst-case combinations of causal and contributing factors (i.e., accident precursors) and how they sequence in time. Such analyses can provide insight in developing effective solutions for LOC, and form the basis for developing test scenarios that can be used in evaluating them. Preliminary findings based on the results of this paper indicate that system failures or malfunctions, crew actions or inactions, vehicle impairment conditions, and vehicle upsets contributed the most to accidents and fatalities, followed by inclement weather or atmospheric disturbances and poor visibility. Follow-on research will include finalizing the analysis through a team consensus process, defining future risks, and developing a comprehensive set of test scenarios with correlation to the accidents, incidents, and future risks. Since enhanced engineering simulations are required for batch and piloted evaluations under realistic LOC precursor conditions, these test scenarios can also serve as a high-level requirement for defining the engineering simulation enhancements needed for generating them.

  20. Structural Equations and Causal Explanations: Some Challenges for Causal SEM

    ERIC Educational Resources Information Center

    Markus, Keith A.

    2010-01-01

    One common application of structural equation modeling (SEM) involves expressing and empirically investigating causal explanations. Nonetheless, several aspects of causal explanation that have an impact on behavioral science methodology remain poorly understood. It remains unclear whether applications of SEM should attempt to provide complete…

  1. Causality violation and paradoxes

    NASA Astrophysics Data System (ADS)

    Krasnikov, S. V.

    1997-03-01

    Paradoxes that can supposedly occur if causality is violated are discussed. It is shown that the existence of ``trajectories of multiplicity zero'' (i.e., trajectories that describe, say, a ball hitting its younger self so that the latter cannot fall into the time machine) is not paradoxical by itself. This apparent paradox can be resolved (at least sometimes) without any harm to local physics or to the time machine. Also a simple model is adduced for which the absence of true paradoxes caused by self-interaction in an acausal world is proved. The conclusion is made that the paradoxes appear if and (within this model) only if the fact is neglected that no conditions fixed to the past of a time machine guarantee that a system remains isolated after it intersects the Cauchy horizon.

  2. Causal electromagnetic interaction equations

    SciTech Connect

    Zinoviev, Yury M.

    2011-02-15

    For the electromagnetic interaction of two particles the relativistic causal quantum mechanics equations are proposed. These equations are solved for the case when the second particle moves freely. The initial wave functions are supposed to be smooth and rapidly decreasing at the infinity. This condition is important for the convergence of the integrals similar to the integrals of quantum electrodynamics. We also consider the singular initial wave functions in the particular case when the second particle mass is equal to zero. The discrete energy spectrum of the first particle wave function is defined by the initial wave function of the free-moving second particle. Choosing the initial wave functions of the free-moving second particle it is possible to obtain a practically arbitrary discrete energy spectrum.

  3. Risk of road accident associated with the use of drugs: a systematic review and meta-analysis of evidence from epidemiological studies.

    PubMed

    Elvik, Rune

    2013-11-01

    This paper is a corrigendum to a previously published paper where errors were detected. The errors have been corrected in this paper. The paper is otherwise identical to the previously published paper. A systematic review and meta-analysis of studies that have assessed the risk of accident associated with the use of drugs when driving is presented. The meta-analysis included 66 studies containing a total of 264 estimates of the effects on accident risk of using illicit or prescribed drugs when driving. Summary estimates of the odds ratio of accident involvement are presented for amphetamines, analgesics, anti-asthmatics, anti-depressives, anti-histamines, benzodiazepines, cannabis, cocaine, opiates, penicillin and zopiclone (a sleeping pill). For most of the drugs, small or moderate increases in accident risk associated with the use of the drugs were found. Information about whether the drugs were actually used while driving and about the doses used was often imprecise. Most studies that have evaluated the presence of a dose-response relationship between the dose of drugs taken and the effects on accident risk confirm the existence of a dose-response relationship. Use of drugs while driving tends to have a larger effect on the risk of fatal and serious injury accidents than on the risk of less serious accidents (usually property-damage-only accidents). The quality of the studies that have assessed risk varied greatly. There was a tendency for the estimated effects of drug use on accident risk to be smaller in well-controlled studies than in poorly controlled studies. Evidence of publication bias was found for some drugs. The associations found cannot be interpreted as causal relationships, principally because most studies do not control very well for potentially confounding factors. PMID:22785089

  4. Risk of road accident associated with the use of drugs: a systematic review and meta-analysis of evidence from epidemiological studies.

    PubMed

    Elvik, Rune

    2013-11-01

    This paper is a corrigendum to a previously published paper where errors were detected. The errors have been corrected in this paper. The paper is otherwise identical to the previously published paper. A systematic review and meta-analysis of studies that have assessed the risk of accident associated with the use of drugs when driving is presented. The meta-analysis included 66 studies containing a total of 264 estimates of the effects on accident risk of using illicit or prescribed drugs when driving. Summary estimates of the odds ratio of accident involvement are presented for amphetamines, analgesics, anti-asthmatics, anti-depressives, anti-histamines, benzodiazepines, cannabis, cocaine, opiates, penicillin and zopiclone (a sleeping pill). For most of the drugs, small or moderate increases in accident risk associated with the use of the drugs were found. Information about whether the drugs were actually used while driving and about the doses used was often imprecise. Most studies that have evaluated the presence of a dose-response relationship between the dose of drugs taken and the effects on accident risk confirm the existence of a dose-response relationship. Use of drugs while driving tends to have a larger effect on the risk of fatal and serious injury accidents than on the risk of less serious accidents (usually property-damage-only accidents). The quality of the studies that have assessed risk varied greatly. There was a tendency for the estimated effects of drug use on accident risk to be smaller in well-controlled studies than in poorly controlled studies. Evidence of publication bias was found for some drugs. The associations found cannot be interpreted as causal relationships, principally because most studies do not control very well for potentially confounding factors.

  5. Expert Causal Reasoning and Explanation.

    ERIC Educational Resources Information Center

    Kuipers, Benjamin

    The relationship between cognitive psychologists and researchers in artificial intelligence carries substantial benefits for both. An ongoing investigation in causal reasoning in medical problem solving systems illustrates this interaction. This paper traces a dialectic of sorts in which three different types of causal resaoning for medical…

  6. Theory-Based Causal Induction

    ERIC Educational Resources Information Center

    Griffiths, Thomas L.; Tenenbaum, Joshua B.

    2009-01-01

    Inducing causal relationships from observations is a classic problem in scientific inference, statistics, and machine learning. It is also a central part of human learning, and a task that people perform remarkably well given its notorious difficulties. People can learn causal structure in various settings, from diverse forms of data: observations…

  7. Causal Inference in Retrospective Studies.

    ERIC Educational Resources Information Center

    Holland, Paul W.; Rubin, Donald B.

    1988-01-01

    The problem of drawing causal inferences from retrospective case-controlled studies is considered. A model for causal inference in prospective studies is applied to retrospective studies. Limitations of case-controlled studies are formulated concerning relevant parameters that can be estimated in such studies. A coffee-drinking/myocardial…

  8. The Development of Causal Categorization

    ERIC Educational Resources Information Center

    Hayes, Brett K.; Rehder, Bob

    2012-01-01

    Two experiments examined the impact of causal relations between features on categorization in 5- to 6-year-old children and adults. Participants learned artificial categories containing instances with causally related features and noncausal features. They then selected the most likely category member from a series of novel test pairs.…

  9. Cognition and asynchronous distribution between human and machine building accidents.

    PubMed

    Martins, Edgard; Soares, Marcelo; Augusto, Lia; Laura, Laura

    2012-01-01

    The creation of meaning in communication is a trading activity, resulting from the construction that is born of the interaction between subjects. That is, the meaning is not inherent to the relationship between words, signs and symbols that arise from negotiating a necessary and unavoidable. As the concepts of sense as discrete and static representations imply a notion of classical computing and design of a cognitive system corresponding conceptions of meaning construction as located and shared among agents implies notions of different computing and cognition. Several efforts have been developed to meet these demands. Among them are the Connectionism (also known as neural networks. Records on aspects of mental health and stress of flight professionals are present in the official reports of the organs of investigation of aviation accidents worldwide since its inception. Problems related to health physical and mental health of pilots (fatigue, stress, physiological and psychosocial problems) account for 19% of causal factors in aircraft accidents. The training seems a paradox when we know that these professionals receive regular training, have high education and technical training of high level. However, problems arise related to the implementation of learning that can be influenced to reduce their cognitive capacity, making it in practice, relatively unable to exercise its functions effectively and safely. PMID:22317220

  10. Attribution as a function of agential distance in a causal chain.

    PubMed

    Kanekar, S; Miranda, J P

    1998-08-01

    The hypothesis that causality and blame will be differently affected by agential distance within a two-step causal chain was tested. A hypothetical medical accident was presented to 360 female college students in India, who gave causality, blame, or punishment judgments about either the proximal agent or the distal agent. The study had a 2 (proximal vs. distal agent) x 2 (high vs. low extenuation) x 2 (mild vs. severe outcome) x 3 (casuality, blame, or punishment judgments) fully crossed, between-subjects factorial design, with 15 participants per cell. In support of the basic hypothesis, more blame and punishment were assigned to the distal agent than to the proximal agent, whereas agential distance did not affect causal attribution. Extenuation was effective on causality and blame judgments only when the outcome was mild, and there was no effect of extenuation on punishment judgments, irrespective of outcome severity. PMID:9679288

  11. Apparent causality affects perceived simultaneity.

    PubMed

    Kohlrausch, Armin; van Eijk, Rob; Juola, James F; Brandt, Inge; van de Par, Steven

    2013-10-01

    The present research addresses the question of how visual predictive information and implied causality affect audio-visual synchrony perception. Previous research has shown a systematic shift in the likelihood of observers to accept audio-leading stimulus pairs as being apparently simultaneous in variants of audio-visual stimulus pairs that differ in (1) the amount of visual predictive information available and (2) the apparent causal relation between the auditory and visual components. An experiment was designed to separate the predictability and causality explanations, and the results indicated that shifts in subjective simultaneity were explained completely by changes in the implied causal relations in the stimuli and that predictability had no added value. Together with earlier findings, these results further indicate that the observed shifts in subjective simultaneity due to causal relations among auditory and visual events do not reflect a mere change in response strategy, but rather result from early multimodal integration processes in event perception.

  12. High prevalence of protein C, protein S, antithrombin deficiency, and Factor V Leiden mutation as a cause of hereditary thrombophilia in patients of venous thromboembolism and cerebrovascular accident

    PubMed Central

    Ali, Nadir; Ayyub, Muhammad; Khan, Saleem Ahmed

    2014-01-01

    Objectives: To determine the frequency of Protein C, Protein S (PC & PS), antithrombin deficiency (AT III) and Factor V Leiden mutation (FVL) as a cause of thrombophilia in the patients with venous thromboembolism (VTE) and cerebrovascular accident (CVA). Methods: It was an observational study conducted at Department of Haematology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan. All patients referred for thrombophilia screening from July 2009 to June 2012 were screened. Patients with evidence of VTE or CVA were screened for PC & PS, AT III deficiency, and FVL. Results: Total 404 patients of age between 1-71 years mean 33 ± 14 with male to female ratio of 2.4:1 had evidence of thrombophilia. Two hundred eighteen (54%) patients presented with CVA, 116 (29%) with deep vein thrombosis (DVT), 42 (10.5%) with pulmonary embolism (PE), and 28 (7.5%) with portal or mesenteric vein thrombosis (PV). Protein C & S deficiency was detected in 35/404 (8.7%), ATIII in 9/404 (2%), and FVL in 25/173 patients (14.5%). The findings were suggestive of a significant association of FVL mutation for developing DVT (OR=11.0, 95% C I 4.6-26.3), CVA (OR=5.7, 95% C I 2.1-15.1), and PV (OR=5.4, 95% C I 1.3-21.9). PC & PS deficiency was a significant risk factor for developing PE (OR=3, 95% C I 0.8-11.4). Conclusion: FVL mutation and Protein C & S are the leading causes of thrombophilia with strong association of Factor V Leiden mutation as risk for developing DVT. PMID:25674132

  13. [Factors influencing the performance of medical teams in the early assessment of exposure to radiation--in accident or man-made radiological disasters].

    PubMed

    Gonen, Anat; Aharonson-Daniel, Limor

    2012-02-01

    "RadioLogical events" are the general term used to describe various scenarios that involve radiological and nuclear mishaps. These may occur in different settings such as in a nuclear plant, during transportation of isotopes, in a medical or industrial venue, as a result of an accident, natural disaster or as a means of terror or war. Radiological events carry dire medical consequences and are therefore of great concern to both the public and the authorities. The recent disaster in Japan brought the issue of the safety of nuclear pLants to the civil populations residing around them to the public eye once again. A nuclear disaster poses a professional challenge to the medical teams that need to treat victims. Studies show that the readiness and willingness to care for radiation victims is influenced by many factors, among them are knowledge and skills, the resources available and more. The ability of triage staff to identify radiation victims and to identify those prone to deteriorate, will have an effect on the staff's feeling of competitiveness and willingness to treat. Risk communication is an important contributor to the ability to handle the situation properly. Good communication can alleviate concerns in the public and mediate the response in a way that will prevent an overflow of the system by "worried well". The aim of this literature review is to describe the factors that encourage the functioning of teams in a radiological event and to identify and highlight the factors that can influence their performance (positively or negatively). PMID:22741203

  14. Normal Accident at Three Mile Island.

    ERIC Educational Resources Information Center

    Perrow, Charles

    1981-01-01

    Discusses some aspects of the accident at the Three Mile Island nuclear power plant. Explains a number of factors involved including the type of accident, warnings, design and equipment failure, operator error, and negative synergy. Presents alternatives to systems with catastrophic potential. (MK)

  15. CausalTrail: Testing hypothesis using causal Bayesian networks

    PubMed Central

    Trampert, Patrick; Lenhof, Hans-Peter

    2015-01-01

    Summary Causal Bayesian Networks are a special class of Bayesian networks in which the hierarchy directly encodes the causal relationships between the variables. This allows to compute the effect of interventions, which are external changes to the system, caused by e.g. gene knockouts or an administered drug. Whereas numerous packages for constructing causal Bayesian networks are available, hardly any program targeted at downstream analysis exists. In this paper we present CausalTrail, a tool for performing reasoning on causal Bayesian networks using the do-calculus. CausalTrail's features include multiple data import methods, a flexible query language for formulating hypotheses, as well as an intuitive graphical user interface. The program is able to account for missing data and thus can be readily applied in multi-omics settings where it is common that not all measurements are performed for all samples. Availability and Implementation CausalTrail is implemented in C++ using the Boost and Qt5 libraries. It can be obtained from https://github.com/dstoeckel/causaltrail PMID:26913195

  16. The Visual Causality Analyst: An Interactive Interface for Causal Reasoning.

    PubMed

    Wang, Jun; Mueller, Klaus

    2016-01-01

    Uncovering the causal relations that exist among variables in multivariate datasets is one of the ultimate goals in data analytics. Causation is related to correlation but correlation does not imply causation. While a number of casual discovery algorithms have been devised that eliminate spurious correlations from a network, there are no guarantees that all of the inferred causations are indeed true. Hence, bringing a domain expert into the casual reasoning loop can be of great benefit in identifying erroneous casual relationships suggested by the discovery algorithm. To address this need we present the Visual Causal Analyst-a novel visual causal reasoning framework that allows users to apply their expertise, verify and edit causal links, and collaborate with the causal discovery algorithm to identify a valid causal network. Its interface consists of both an interactive 2D graph view and a numerical presentation of salient statistical parameters, such as regression coefficients, p-values, and others. Both help users in gaining a good understanding of the landscape of causal structures particularly when the number of variables is large. Our framework is also novel in that it can handle both numerical and categorical variables within one unified model and return plausible results. We demonstrate its use via a set of case studies using multiple practical datasets.

  17. [Accident analytics for structural traumas of the cervical spine].

    PubMed

    Hartwig, E; Elbel, M; Schultheiss, M; Kettler, A; Kinzl, L; Kramer, M

    2004-12-01

    The differentiation between degenerative syndromes of the cervical spine and post-traumatic symptoms requires accident analysis. Experiments with human subjects yield data only in the low-energy range, and there are still no accident analyses of structural traumas of the cervical spine. From 1 January 2000 to 30 April 2002, 15 patients with structural injuries to the cervical spine due to car accidents were treated in the Department of Trauma Surgery of the University of Ulm. In 11 of these cases, the DEKRA Ulm completed an appraisal of the accident process.With lateral impacts, structural injuries to the cervical spine can occur even at speeds of only ca 10 km/h. Injuries to the alar ligaments are produced by frontal collisions with substantial differences in speed. Data from accident analysis of structural injuries to the cervical spine must be taken into consideration in causality examinations of distortions of the cervical spine.

  18. Multilevel Causal Analysis of Socio-Psychological and Behavioral Factors of Health Providers and Clients That Affect Health Behavioral Modification in Obesity

    PubMed Central

    Intarakamhang, Ungsinun; Intarakamhang, Patrawut

    2015-01-01

    The Comprehensive Lifestyle Intervention, which integrates behavioral therapy, is the main ideal management of the clients with obesity. Various socio-psychological factors can affect outcome of the program. The Purposes: To determine the socio-psychological factors at the client and provider groups that affect health behavior modification (HBM) in obese clients, and to investigate the cross-level interaction of factors that affect HBM. The samples included 87 health providers and 412 clients using stratified random sampling. Hierarchical Linear Model was used to analyze in a questionnaire with reliability of 0.8-0.9. Results: 1) for the clients: 1.1) Attitudes towards healthy behavior (AHB), health-related knowledge, and trust in the provider predicted self-efficacy at 49.40%; 1.2) AHB and support from the provider predicted self-regulation at 75.50%; and 1.3) AHB, trust in the provider and support from the provider predicted self-care at 26.6%. 2) for the health providers: 2.1) Health quotient (HQ), project management (PM), support from the team, and the team emotional quotient (EQ) predicted self-efficacy at 71.30%; 2.2) PM and HQ predicted self-regulation at 51.60%; and 2.3) PM, team EQ and HQ predicted self-care at 77.30%., 3) No cross-level interaction of factors between the clients and the providers was identified to affect HBM. Conclusion: The obese client’s AHB is the factor that significantly influenced self-efficacy, self-regulation and self-care (3SELF).At the health provider level, both HQ and PM significantly influenced 3SELF. Behavioral. PMID:26153178

  19. Causal Rasch models

    PubMed Central

    Stenner, A. Jackson; Fisher, William P.; Stone, Mark H.; Burdick, Donald S.

    2013-01-01

    Rasch's unidimensional models for measurement show how to connect object measures (e.g., reader abilities), measurement mechanisms (e.g., machine-generated cloze reading items), and observational outcomes (e.g., counts correct on reading instruments). Substantive theory shows what interventions or manipulations to the measurement mechanism can be traded off against a change to the object measure to hold the observed outcome constant. A Rasch model integrated with a substantive theory dictates the form and substance of permissible interventions. Rasch analysis, absent construct theory and an associated specification equation, is a black box in which understanding may be more illusory than not. Finally, the quantitative hypothesis can be tested by comparing theory-based trade-off relations with observed trade-off relations. Only quantitative variables (as measured) support such trade-offs. Note that to test the quantitative hypothesis requires more than manipulation of the algebraic equivalencies in the Rasch model or descriptively fitting data to the model. A causal Rasch model involves experimental intervention/manipulation on either reader ability or text complexity or a conjoint intervention on both simultaneously to yield a successful prediction of the resultant observed outcome (count correct). We conjecture that when this type of manipulation is introduced for individual reader text encounters and model predictions are consistent with observations, the quantitative hypothesis is sustained. PMID:23986726

  20. History, causality, and sexology.

    PubMed

    Money, John

    2003-08-01

    In 1896, Krafft-Ebing published Psychopathia Sexualis. Popularly defined as hereditary weakness or taintedness in the family pedigree, degeneracy was called upon as a causal explanation for perversions of the sexual instinct. Although Krafft-Ebing accepted Karl Ulrichs proposal that homosexuality could be innate and probably located in the brain, he paid little attention to neuropathological sexology. Alfred Binet challenged Krafft-Ebing's orthodoxy by explaining fetishism in terms of associative learning, to which Krafft-Ebing's response was that only those with a hereditary taint would be vulnerable. Thus did the venerable nature-nurture antithesis maintain its rhetoric, even to the present day. Krafft-Ebing died too soon to meet the Freudian challenge of endopsychic determinism, and too soon also to encounter the idea of a developmental multivariate outcome of what I have termed the lovemap. Like other brain maps, for example the languagemap, the lovemap requires an intact human brain in which to develop. The personalized content of the lovemap has access to the brain by way of the special senses.

  1. Investigating accident causation through information network modelling.

    PubMed

    Griffin, T G C; Young, M S; Stanton, N A

    2010-02-01

    Management of risk in complex domains such as aviation relies heavily on post-event investigations, requiring complex approaches to fully understand the integration of multi-causal, multi-agent and multi-linear accident sequences. The Event Analysis of Systemic Teamwork methodology (EAST; Stanton et al. 2008) offers such an approach based on network models. In this paper, we apply EAST to a well-known aviation accident case study, highlighting communication between agents as a central theme and investigating the potential for finding agents who were key to the accident. Ultimately, this work aims to develop a new model based on distributed situation awareness (DSA) to demonstrate that the risk inherent in a complex system is dependent on the information flowing within it. By identifying key agents and information elements, we can propose proactive design strategies to optimize the flow of information and help work towards avoiding aviation accidents. Statement of Relevance: This paper introduces a novel application of an holistic methodology for understanding aviation accidents. Furthermore, it introduces an ongoing project developing a nonlinear and prospective method that centralises distributed situation awareness and communication as themes. The relevance of findings are discussed in the context of current ergonomic and aviation issues of design, training and human-system interaction. PMID:20099174

  2. Detecting causality in complex ecosystems.

    PubMed

    Sugihara, George; May, Robert; Ye, Hao; Hsieh, Chih-hao; Deyle, Ethan; Fogarty, Michael; Munch, Stephan

    2012-10-26

    Identifying causal networks is important for effective policy and management recommendations on climate, epidemiology, financial regulation, and much else. We introduce a method, based on nonlinear state space reconstruction, that can distinguish causality from correlation. It extends to nonseparable weakly connected dynamic systems (cases not covered by the current Granger causality paradigm). The approach is illustrated both by simple models (where, in contrast to the real world, we know the underlying equations/relations and so can check the validity of our method) and by application to real ecological systems, including the controversial sardine-anchovy-temperature problem.

  3. Human causal discovery from observational data.

    PubMed Central

    Hashem, A. I.; Cooper, G. F.

    1996-01-01

    Utilizing Bayesian belief networks as a model of causality, we examined medical students' ability to discover causal relationships from observational data. Nine sets of patient cases were generated from relatively simple causal belief networks by stochastic simulation. Twenty participants examined the data sets and attempted to discover the underlying causal relationships. Performance was poor in general, except at discovering the absence of a causal relationship. This work supports the potential for combining human and computer methods for causal discovery. PMID:8947621

  4. World commercial aircraft accidents

    SciTech Connect

    Kimura, C.Y.

    1993-01-01

    This report is a compilation of all accidents world-wide involving aircraft in commercial service which resulted in the loss of the airframe or one or more fatality, or both. This information has been gathered in order to present a complete inventory of commercial aircraft accidents. Events involving military action, sabotage, terrorist bombings, hijackings, suicides, and industrial ground accidents are included within this list. Included are: accidents involving world commercial jet aircraft, world commercial turboprop aircraft, world commercial pistonprop aircraft with four or more engines and world commercial pistonprop aircraft with two or three engines from 1946 to 1992. Each accident is presented with information in the following categories: date of the accident, airline and its flight numbers, type of flight, type of aircraft, aircraft registration number, construction number/manufacturers serial number, aircraft damage, accident flight phase, accident location, number of fatalities, number of occupants, cause, remarks, or description (brief) of the accident, and finally references used. The sixth chapter presents a summary of the world commercial aircraft accidents by major aircraft class (e.g. jet, turboprop, and pistonprop) and by flight phase. The seventh chapter presents several special studies including a list of world commercial aircraft accidents for all aircraft types with 100 or more fatalities in order of decreasing number of fatalities, a list of collision accidents involving commercial aircrafts, and a list of world commercial aircraft accidents for all aircraft types involving military action, sabotage, terrorist bombings, and hijackings.

  5. Pilot-error accidents: male vs female.

    PubMed

    Vail, G J; Ekman, L G

    1986-12-01

    In this study, general aviation accident records from the files of the National Transportation Safety Board (NTSB), have been analysed by gender to observe the number and rate of pilot-error related accidents from 1972 to 1981 inclusive. If both females and males have no difference in performance, then data would have indicated similarities of accident rates and types of injuries. Males had a higher rate of accidents than females, and a higher portion of the male accidents resulted in fatalities or serious injuries than for females. Type of certificate, age, total flight time, flight time in type of aircraft, phase of operation, category of flying, degree of injury, specific cause factors, cause factor miscellaneous acts/conditions were analysed, taking the total number of United States Active Civilian General Aviation Pilots into consideration. The data did indicate a difference in all variables.

  6. "Head take you": causal attributions of mental illness in Jamaica.

    PubMed

    Arthur, Carlotta M; Whitley, Rob

    2015-02-01

    Causal attributions are a key factor in explanatory models of illness; however, little research on causal attributions of mental illness has been conducted in developing nations in the Caribbean, including Jamaica. Explanatory models of mental illness may be important in understanding illness experience and be a crucial factor in mental health service seeking and utilization. We explored causal attributions of mental illness in Jamaica by conducting 20 focus groups, including 16 community samples, 2 patient samples, and 2 samples of caregivers of patients, with a total of 159 participants. The 5 most commonly endorsed causal attributions of mental illness are discussed: (a) drug-related causes, including ganja (marijuana); (b) biological causes, such as chemical imbalance, familial transmission, and "blood"; (c) psychological causes, including stress and thinking too much; (d) social causes, such as relationship problems and job loss; and (e) spiritual or religious causes, including Obeah.

  7. [Causality in cardiology: concepts in evolution].

    PubMed

    Méndez, Gustavo F

    2005-01-01

    This paper describes several concepts about causality from Empedocles, Aristoteles and Galeno, to Koch and Hill and the evolution of these concepts related to cardiovascular diseases. Also defines cause and risk, and the philosophical theories about scientific knowledge: inductive versus refutation analysis. On these basis, the study of cardiovascular disease's causality, especially coronary heart disease, allows us the identification of several risk factors involved in its development. However, even with the presently coronary heart disease risk charts (from Framingham and European studies) the higher probability for the development of a cardiovascular ischemic event is around 40%, establishing an important degree of uncertainty. With the improvement in molecular biology techniques, genetics have attempted to analyse several genetic polymorphisms in search of the origin of coronary heart disease. Unfortunately, less than 10% of these polymorphisms have had a positive correlation with coronary heart disease being of minor risk that those obtained for having the diagnosis of type 2 diabetes mellitus or hypercholesterolemia. On these basis, the requirement of new population research projects in which clinical and genetic risk factors are to be studied for the appropriate understanding of the causality process of cardiovascular diseases must be a worldwide priority.

  8. Designing an Experimental "Accident"

    ERIC Educational Resources Information Center

    Picker, Lester

    1974-01-01

    Describes an experimental "accident" that resulted in much student learning, seeks help in the identification of nematodes, and suggests biology teachers introduce similar accidents into their teaching to stimulate student interest. (PEB)

  9. Causal learning with local computations.

    PubMed

    Fernbach, Philip M; Sloman, Steven A

    2009-05-01

    The authors proposed and tested a psychological theory of causal structure learning based on local computations. Local computations simplify complex learning problems via cues available on individual trials to update a single causal structure hypothesis. Structural inferences from local computations make minimal demands on memory, require relatively small amounts of data, and need not respect normative prescriptions as inferences that are principled locally may violate those principles when combined. Over a series of 3 experiments, the authors found (a) systematic inferences from small amounts of data; (b) systematic inference of extraneous causal links; (c) influence of data presentation order on inferences; and (d) error reduction through pretraining. Without pretraining, a model based on local computations fitted data better than a Bayesian structural inference model. The data suggest that local computations serve as a heuristic for learning causal structure.

  10. RECENT LASER ACCIDENTS AT DEPARTMENT OF ENERGY LABORATORIES

    SciTech Connect

    ODOM, CONNON R.

    2007-02-02

    Recent laser accidents and incidents at research laboratories across the Department of Energy complex are reviewed in this paper. Factors that contributed to the accidents are examined. Conclusions drawn from the accident reports are summarized and compared. Control measures that could have been implemented to prevent the accidents will be summarized and compared. Recommendations for improving laser safety programs are outlined and progress toward achieving them are summarized.

  11. Noise as an explanatory factor in work-related fatality reports

    PubMed Central

    Deshaies, Pierre; Martin, Richard; Belzile, Danny; Fortier, Pauline; Laroche, Chantal; Leroux, Tony; Nélisse, Hugues; Girard, Serge-André; Arcand, Robert; Poulin, Maurice; Picard, Michel

    2015-01-01

    Noise exposure in the workplace is a common reality in Québec, Canada as it is elsewhere. However, the extent to which noise acts as a causal or contributive factor in industrial work-related accidents has not been studied thoroughly despite its plausibility. This article aims to describe the importance or potential importance, during investigations looking into the specific causes of each work-related fatal accident, of noise as an explanatory factor. The written information contained in the accident reports pertaining to contextual and technical elements were used. The study used multiple case qualitative content analysis. This descriptive study was based on the content analysis of the 788 reports from the Commission de la santé et de la sécurité du travail du Québec [Workers’ Compensation Board (WCB)] investigating the fatal work-related accidents between 1990 and 2005. The study was descriptive (number and percentages). Noise was explicitly stated as one of the explanatory factors for the fatal outcome in 2.2% (17/788) of the fatal accidents, particularly when the work involved vehicular movement or the need to communicate between workers. Noise was not typically considered a unique cause in the accident, notably because the investigators considered that the accident would have probably occurred due to other risk factors (for example, disregard of safety rules, shortcomings in work methods, and inadequate training). Noise is an important risk factor when communication is involved in work. Since noise is ubiquitous and may also interfere with vigilance and other risk factors for accidents, it may be a much more important contributing factor to accidents than is currently recognized. PMID:26356371

  12. Noise as an explanatory factor in work-related fatality reports.

    PubMed

    Deshaies, Pierre; Martin, Richard; Belzile, Danny; Fortier, Pauline; Laroche, Chantal; Leroux, Tony; Nélisse, Hugues; Girard, Serge-André; Arcand, Robert; Poulin, Maurice; Picard, Michel

    2015-01-01

    Noise exposure in the workplace is a common reality in Québec, Canada as it is elsewhere. However, the extent to which noise acts as a causal or contributive factor in industrial work-related accidents has not been studied thoroughly despite its plausibility. This article aims to describe the importance or potential importance, during investigations looking into the specific causes of each work-related fatal accident, of noise as an explanatory factor. The written information contained in the accident reports pertaining to contextual and technical elements were used. The study used multiple case qualitative content analysis. This descriptive study was based on the content analysis of the 788 reports from the Commission de la santé et de la sécurité du travail du Québec [Workers' Compensation Board (WCB)] investigating the fatal work-related accidents between 1990 and 2005. The study was descriptive (number and percentages). Noise was explicitly stated as one of the explanatory factors for the fatal outcome in 2.2% (17/788) of the fatal accidents, particularly when the work involved vehicular movement or the need to communicate between workers. Noise was not typically considered a unique cause in the accident, notably because the investigators considered that the accident would have probably occurred due to other risk factors (for example, disregard of safety rules, shortcomings in work methods, and inadequate training). Noise is an important risk factor when communication is involved in work. Since noise is ubiquitous and may also interfere with vigilance and other risk factors for accidents, it may be a much more important contributing factor to accidents than is currently recognized.

  13. Road accidents caused by drivers falling asleep.

    PubMed

    Sagberg, F

    1999-11-01

    About 29600 Norwegian accident-involved drivers received a questionnaire about the last accident reported to their insurance company. About 9200 drivers (31%) returned the questionnaire. The questionnaire contained questions about sleep or fatigue as contributing factors to the accident. In addition, the drivers reported whether or not they had fallen asleep some time whilst driving. and what the consequences had been. Sleep or drowsiness was a contributing factor in 3.9% of all accidents, as reported by drivers who were at fault for the accident. This factor was strongly over-represented in night-time accidents (18.6%), in running-off-the-road accidents (8.3%), accidents after driving more than 150 km on one trip (8.1%), and personal injury accidents (7.3%). A logistic regression analysis showed that the following additional factors made significant and independent contributions to increasing the odds of sleep involvement in an accident: dry road, high speed limit, driving one's own car, not driving the car daily, high education, and few years of driving experience. More male than female drivers were involved in sleep-related accidents, but this seems largely to be explained by males driving relatively more than females on roads with high speed limits. A total of 10% of male drivers and 4% of females reported to have fallen asleep while driving during the last 12 months. A total of 4% of these events resulted in an accident. The most frequent consequence of falling asleep--amounting to more than 40% of the reported incidents--was crossing of the right edge-line before awaking, whereas crossing of the centreline was reported by 16%. Drivers' lack of awareness of important precursors of falling asleep--like highway hypnosis, driving without awareness, and similar phenomena--as well as a reluctance to discontinue driving despite feeling tired are pointed out as likely contributors to sleep-related accidents. More knowledge about the drivers' experiences immediately

  14. Causal Inference in Public Health

    PubMed Central

    Glass, Thomas A.; Goodman, Steven N.; Hernán, Miguel A.; Samet, Jonathan M.

    2014-01-01

    Causal inference has a central role in public health; the determination that an association is causal indicates the possibility for intervention. We review and comment on the long-used guidelines for interpreting evidence as supporting a causal association and contrast them with the potential outcomes framework that encourages thinking in terms of causes that are interventions. We argue that in public health this framework is more suitable, providing an estimate of an action’s consequences rather than the less precise notion of a risk factor’s causal effect. A variety of modern statistical methods adopt this approach. When an intervention cannot be specified, causal relations can still exist, but how to intervene to change the outcome will be unclear. In application, the often-complex structure of causal processes needs to be acknowledged and appropriate data collected to study them. These newer approaches need to be brought to bear on the increasingly complex public health challenges of our globalized world. PMID:23297653

  15. [Snake bite accidents in children in Costa Rica: epidemiology and determination of risk factors in the development of abscess and necrosis].

    PubMed

    Saborío, P; González, M; Cambronero, M

    1998-02-01

    A retrospective epidemiological analysis is presented of 80 snakebites in children admitted to the Pediatrics Service of Tony Facio Hospital in Limón, Costa Rica, between 1985 and 1995. An overall incidence rate of 20 snakebite accidents per 100,000 inhabitants per year was calculated for the region in that period. However, a higher incidence was described in some counties (36 and 30 cases per 100,000 inhabitants in Talamanca and Siquirres, respectively). Most of the cases occurred in February and November, between 16:00 and 19:00 hr. The mean age of the affected children was 8.67 +/- 2.66 years. No significant difference was found between genders. Thirty-three children affected (41.2%) were members of the local indigenous groups and 31 (38.8%) were residents of Talamanca County. The species of snake responsible were identified in 58.4% of cases, with Bothrops asper being the most important. The lower extremities were the most important primary site affected (86.3%). The most common clinical complications described in the study group were abscess formation (11.25%), necrosis (10%), renal failure (3.75%), compartmental syndrome (2.5%) and anaphylactic shock (1.25%). The overall mortality was 2.5%. Statistical analysis of the risk factors relating to the two most common complications showed that the condition of coming from Talamanca County (P = 0.02), damage in the proximal extremities (P = 0.02), a prothrombin time < 2% (P = 0.01) and serum fibrinogen levels < 100 g/dl (P = 0.01) were risk factors for the development of abscesses. The grade of severity of the snakebite (P = 0.018) and serum fibrinogen levels < 100 g/dl were associated with development of necrosis. All of the patients with necrosis and abscesses also experienced two or more of the risk factors that correlated with a sensitivity of 100% and a specificity of 67% for the development of abscess, and 87% sensitivity and 88% specificity for necrotic complications. According to these data, snakebite

  16. Potassium iodide for thyroid blockade in a reactor accident: administrative policies that govern its use.

    PubMed

    Becker, D V; Zanzonico, P

    1997-04-01

    A marked increase in thyroid cancer among young children who were in the vicinity of the Chernobyl nuclear power plant at the time of the 1986 accident strongly suggests a possible causal relationship to the large amounts of radioactive iodine isotopes in the resulting fallout. Although remaining indoors, restricting consumption of locally produced milk and foodstuffs, and evacuation are important strategies in a major breach-of-containment accident, stable potassium iodide (KI) prophylaxis given shortly before or immediately after exposure can reduce greatly the thyroidal accumulation of radioiodines and the resulting radiation dose. Concerns about possible side effects of large-scale, medically unsupervised KI consumption largely have been allayed in light of the favorable experience in Poland following the Chernobyl accident; 16 million persons received single administrations of KI with only rare occurrence of side effects and with a probable 40% reduction in projected thyroid radiation dose. Despite the universal acceptance of KI as an effective thyroid protective agent, supplies of KI in the US are not available for public distribution in the event of a reactor accident largely because government agencies have argued that stockpiling and distribution of KI to other than emergency workers cannot be recommended in light of difficult distribution logistics, problematic administrative issue, and a calculated low cost-effectiveness. However, KI in tablet form is expensive and has a long shelf life, and many countries have largely stockpiles and distribution programs. The World Health Organization recognizes the benefits of stable KI and urges its general availability. At present there are 110 operating nuclear power plants in the US and more than 300 in the rest of the world. These reactors product 17% of the world's electricity and in some countries up to 60-70% of the total electrical energy. Almost all US nuclear power plants have multistage containment

  17. Potassium iodide for thyroid blockade in a reactor accident: administrative policies that govern its use.

    PubMed

    Becker, D V; Zanzonico, P

    1997-04-01

    A marked increase in thyroid cancer among young children who were in the vicinity of the Chernobyl nuclear power plant at the time of the 1986 accident strongly suggests a possible causal relationship to the large amounts of radioactive iodine isotopes in the resulting fallout. Although remaining indoors, restricting consumption of locally produced milk and foodstuffs, and evacuation are important strategies in a major breach-of-containment accident, stable potassium iodide (KI) prophylaxis given shortly before or immediately after exposure can reduce greatly the thyroidal accumulation of radioiodines and the resulting radiation dose. Concerns about possible side effects of large-scale, medically unsupervised KI consumption largely have been allayed in light of the favorable experience in Poland following the Chernobyl accident; 16 million persons received single administrations of KI with only rare occurrence of side effects and with a probable 40% reduction in projected thyroid radiation dose. Despite the universal acceptance of KI as an effective thyroid protective agent, supplies of KI in the US are not available for public distribution in the event of a reactor accident largely because government agencies have argued that stockpiling and distribution of KI to other than emergency workers cannot be recommended in light of difficult distribution logistics, problematic administrative issue, and a calculated low cost-effectiveness. However, KI in tablet form is expensive and has a long shelf life, and many countries have largely stockpiles and distribution programs. The World Health Organization recognizes the benefits of stable KI and urges its general availability. At present there are 110 operating nuclear power plants in the US and more than 300 in the rest of the world. These reactors product 17% of the world's electricity and in some countries up to 60-70% of the total electrical energy. Almost all US nuclear power plants have multistage containment

  18. Regional differences in mercury levels in aquatic ecosystems: A discussion of possible causal factors with implications for the Tennessee river system and the Northern Hemisphere

    NASA Astrophysics Data System (ADS)

    Joslin, J. Devereux

    1994-07-01

    Concern about mercury pollution from atmospheric deposition has risen markedly in the last decade because of high levels of mercury in freshwater fish from relatively pristine waters. Whereas high concentrations have been found principally in Canada, the northern United States, and Scandinavia, they have also recently been observed throughout much of Florida. Recent surveys of the Tennessee River system, however, have found no locations where fish levels exceed EPA guidelines for fish consumption. This paper evaluates a number of factors that may cause certain regions in the northern hemisphere to experience unacceptable fish mercury levels while other regions do not. Relevant regional differences include: (1) Waters of the Tennessee River system are generally nonacidic (pH>6) and well buffered, whereas 16%, 22%, and 40% of the lakes in upper Midwest, Northeast, and Florida, respectively, have acid-neutralizing capacities below 50 µeq/liter. Acidity correlates highly with fish mercury levels in a number of lake surveys, and experimental manipulations of acidity have significantly raised fish mercury levels. (2) The ratio of land area to water surface area in the Tennessee Valley averages about 30, whereas it is 15 in the upper Midwest and 6 in Florida. Low ratios allow mercury in precipitation to be directly deposited to aquatic bodies, without an opportunity for the mercury to be sequestered by terrestrial ecosystems. (3) Stream organic matter concentrations in Florida, the upper Midwest, and Sweden are 2 10 times those in the Tennessee Valley. Mercury binds strongly to organic matter, and organic matter transport in runoff is a major pathway by which mercury enters aquatic ecosystems.

  19. Risk factors for bovine respiratory disease in Australian feedlot cattle: use of a causal diagram-informed approach to estimate effects of animal mixing and movements before feedlot entry.

    PubMed

    Hay, K E; Barnes, T S; Morton, J M; Clements, A C A; Mahony, T J

    2014-11-01

    A nationwide longitudinal study was conducted to investigate risk factors for bovine respiratory disease (BRD) in cattle in Australian feedlots. After induction (processing), cattle were placed in feedlot pens (cohorts) and monitored for occurrence of BRD over the first 50 days on feed. Data from a national cattle movement database were used to derive variables describing mixing of animals with cattle from other farms, numbers of animals in groups before arrival at the feedlot, exposure of animals to saleyards before arrival at the feedlot, and the timing and duration of the animal's move to the vicinity of the feedlot. Total and direct effects for each risk factor were estimated using a causal diagram-informed process to determine covariates to include in four-level Bayesian logistic regression models. Mixing, group size and timing of the animal's move to the feedlot were important predictors of BRD. Animals not mixed with cattle from other farms prior to 12 days before induction and then exposed to a high level of mixing (≥4 groups of animals mixed) had the highest risk of developing BRD (OR 3.7) compared to animals mixed at least 4 weeks before induction with less than 4 groups forming the cohort. Animals in groups formed at least 13 days before induction comprising 100 or more (OR 0.5) or 50-99 (OR 0.8) were at reduced risk compared to those in groups of less than 50 cattle. Animals moved to the vicinity of the feedlot at least 27 days before induction were at reduced risk (OR 0.4) compared to cattle undergoing short-haul transportation (<6h) to the feedlot within a day of induction, while those experiencing longer transportation durations (6h or more) within a day of induction were at slightly increased risk (OR 1.2). Knowledge of these risk factors could potentially be used to inform management decisions to reduce the risk of BRD in feedlot cattle.

  20. An Evaluation of Active Learning Causal Discovery Methods for Reverse-Engineering Local Causal Pathways of Gene Regulation.

    PubMed

    Ma, Sisi; Kemmeren, Patrick; Aliferis, Constantin F; Statnikov, Alexander

    2016-01-01

    Reverse-engineering of causal pathways that implicate diseases and vital cellular functions is a fundamental problem in biomedicine. Discovery of the local causal pathway of a target variable (that consists of its direct causes and direct effects) is essential for effective intervention and can facilitate accurate diagnosis and prognosis. Recent research has provided several active learning methods that can leverage passively observed high-throughput data to draft causal pathways and then refine the inferred relations with a limited number of experiments. The current study provides a comprehensive evaluation of the performance of active learning methods for local causal pathway discovery in real biological data. Specifically, 54 active learning methods/variants from 3 families of algorithms were applied for local causal pathways reconstruction of gene regulation for 5 transcription factors in S. cerevisiae. Four aspects of the methods' performance were assessed, including adjacency discovery quality, edge orientation accuracy, complete pathway discovery quality, and experimental cost. The results of this study show that some methods provide significant performance benefits over others and therefore should be routinely used for local causal pathway discovery tasks. This study also demonstrates the feasibility of local causal pathway reconstruction in real biological systems with significant quality and low experimental cost.

  1. An Evaluation of Active Learning Causal Discovery Methods for Reverse-Engineering Local Causal Pathways of Gene Regulation

    PubMed Central

    Ma, Sisi; Kemmeren, Patrick; Aliferis, Constantin F.; Statnikov, Alexander

    2016-01-01

    Reverse-engineering of causal pathways that implicate diseases and vital cellular functions is a fundamental problem in biomedicine. Discovery of the local causal pathway of a target variable (that consists of its direct causes and direct effects) is essential for effective intervention and can facilitate accurate diagnosis and prognosis. Recent research has provided several active learning methods that can leverage passively observed high-throughput data to draft causal pathways and then refine the inferred relations with a limited number of experiments. The current study provides a comprehensive evaluation of the performance of active learning methods for local causal pathway discovery in real biological data. Specifically, 54 active learning methods/variants from 3 families of algorithms were applied for local causal pathways reconstruction of gene regulation for 5 transcription factors in S. cerevisiae. Four aspects of the methods’ performance were assessed, including adjacency discovery quality, edge orientation accuracy, complete pathway discovery quality, and experimental cost. The results of this study show that some methods provide significant performance benefits over others and therefore should be routinely used for local causal pathway discovery tasks. This study also demonstrates the feasibility of local causal pathway reconstruction in real biological systems with significant quality and low experimental cost. PMID:26939894

  2. A Complex Systems Approach to Causal Discovery in Psychiatry

    PubMed Central

    Saxe, Glenn N.; Statnikov, Alexander; Fenyo, David; Ren, Jiwen; Li, Zhiguo; Prasad, Meera; Wall, Dennis; Bergman, Nora; Briggs, Ernestine C.; Aliferis, Constantin

    2016-01-01

    Conventional research methodologies and data analytic approaches in psychiatric research are unable to reliably infer causal relations without experimental designs, or to make inferences about the functional properties of the complex systems in which psychiatric disorders are embedded. This article describes a series of studies to validate a novel hybrid computational approach–the Complex Systems-Causal Network (CS-CN) method–designed to integrate causal discovery within a complex systems framework for psychiatric research. The CS-CN method was first applied to an existing dataset on psychopathology in 163 children hospitalized with injuries (validation study). Next, it was applied to a much larger dataset of traumatized children (replication study). Finally, the CS-CN method was applied in a controlled experiment using a ‘gold standard’ dataset for causal discovery and compared with other methods for accurately detecting causal variables (resimulation controlled experiment). The CS-CN method successfully detected a causal network of 111 variables and 167 bivariate relations in the initial validation study. This causal network had well-defined adaptive properties and a set of variables was found that disproportionally contributed to these properties. Modeling the removal of these variables resulted in significant loss of adaptive properties. The CS-CN method was successfully applied in the replication study and performed better than traditional statistical methods, and similarly to state-of-the-art causal discovery algorithms in the causal detection experiment. The CS-CN method was validated, replicated, and yielded both novel and previously validated findings related to risk factors and potential treatments of psychiatric disorders. The novel approach yields both fine-grain (micro) and high-level (macro) insights and thus represents a promising approach for complex systems-oriented research in psychiatry. PMID:27028297

  3. Important factors governing exposure of the population and countermeasure application in rural settlements of the Russian Federation in the long-term after the Chernobyl accident.

    PubMed

    Fesenko, S; Jacob, P; Alexakhin, R; Sanzharova, N I; Panov, A; Fesenko, G; Cecille, L

    2001-01-01

    Rural settlements located in areas of the Russian Federation contaminated after the Chernobyl accident and exceeding an annual dose of 1 mSv a-1 have been classified according to 137Cs contamination density, internal dose and the neighbourhood of forests. It has been shown that, with the exception of the most contaminated areas, the internal doses decreased in accordance with a decline in 137Cs availability for plant root uptake. An inverse tendency was observed in areas with 137Cs contamination above 555 kBq m-2 which can be explained by a reduction or even termination of countermeasure application and by an increasing consumption of forest products in areas where restrictive countermeasures are still implemented. Twenty-seven settlements have been studied to estimate the effectiveness of countermeasures applied previously and to identify the most important factors governing the radiation exposure to the population and its change with time. It has been shown that the effectiveness of countermeasures which resulted in a decrease of up to 40% of doses has a tendency to decline in the long term. The need for continuation of remediation in rural settlements was evaluated both for selected settlements and extrapolated to the whole contaminated area and it has been shown that the application of countermeasures will be of importance at least up to the year 2045. Rather high effectiveness in terms of internal dose reduction (factor of 2-2.5) of radical improvement (disking, ploughing and reseeding) and administration of Cs binders to animals (Ferrocyn) was demonstrated for the selected settlements. It could be demonstrated that for forest-remote settlements there is a linear dependence between internal dose normalised to the density of contamination and the proportion of peat soils around settlements. For near-forest settlements, this dependence was less pronounced which can be explained by the high contribution of forest food products to the internal dose. Milk is still

  4. Causality in physiological signals.

    PubMed

    Müller, Andreas; Kraemer, Jan F; Penzel, Thomas; Bonnemeier, Hendrik; Kurths, Jürgen; Wessel, Niels

    2016-05-01

    Health is one of the most important non-material assets and thus also has an enormous influence on material values, since treating and preventing diseases is expensive. The number one cause of death worldwide today originates in cardiovascular diseases. For these reasons the aim of understanding the functions and the interactions of the cardiovascular system is and has been a major research topic throughout various disciplines for more than a hundred years. The purpose of most of today's research is to get as much information as possible with the lowest possible effort and the least discomfort for the subject or patient, e.g. via non-invasive measurements. A family of tools whose importance has been growing during the last years is known under the headline of coupling measures. The rationale for this kind of analysis is to identify the structure of interactions in a system of multiple components. Important information lies for example in the coupling direction, the coupling strength, and occurring time lags. In this work, we will, after a brief general introduction covering the development of cardiovascular time series analysis, introduce, explain and review some of the most important coupling measures and classify them according to their origin and capabilities in the light of physiological analyses. We will begin with classical correlation measures, go via Granger-causality-based tools, entropy-based techniques (e.g. momentary information transfer), nonlinear prediction measures (e.g. mutual prediction) to symbolic dynamics (e.g. symbolic coupling traces). All these methods have contributed important insights into physiological interactions like cardiorespiratory coupling, neuro-cardio-coupling and many more. Furthermore, we will cover tools to detect and analyze synchronization and coordination (e.g. synchrogram and coordigram). As a last point we will address time dependent couplings as identified using a recent approach employing ensembles of time series. The

  5. Different Kinds of Causality in Event Cognition

    ERIC Educational Resources Information Center

    Radvansky, Gabriel A.; Tamplin, Andrea K.; Armendarez, Joseph; Thompson, Alexis N.

    2014-01-01

    Narrative memory is better for information that is more causally connected and occurs at event boundaries, such as a causal break. However, it is unclear whether there are common or distinct influences of causality. For the event boundaries that arise as a result of causal breaks, the events that follow may subsequently become more causally…

  6. Road accidents and business cycles in Spain.

    PubMed

    Rodríguez-López, Jesús; Marrero, Gustavo A; González, Rosa Marina; Leal-Linares, Teresa

    2016-11-01

    This paper explores the causes behind the downturn in road accidents in Spain across the last decade. Possible causes are grouped into three categories: Institutional factors (a Penalty Point System, PPS, dating from 2006), technological factors (active safety and passive safety of vehicles), and macroeconomic factors (the Great recession starting in 2008, and an increase in fuel prices during the spring of 2008). The PPS has been blessed by incumbent authorities as responsible for the decline of road fatalities in Spain. Using cointegration techniques, the GDP growth rate, the fuel price, the PPS, and technological items embedded in motor vehicles appear to be statistically significantly related with accidents. Importantly, PPS is found to be significant in reducing fatal accidents. However, PPS is not significant for non-fatal accidents. In view of these results, we conclude that road accidents in Spain are very sensitive to the business cycle, and that the PPS influenced the severity (fatality) rather than the quantity of accidents in Spain. Importantly, technological items help explain a sizable fraction in accidents downturn, their effects dating back from the end of the nineties.

  7. Remote control continuous mining machine crushing accident data study

    SciTech Connect

    2006-05-11

    A committee was formed to identify norms and trends in remote control continuous miner crushing accidents as part of US MSHA's efforts to reduce and eliminate these types of accidents. The committee was tasked with collecting, reviewing, and evaluating remote control accident data to identify significant factors that could possibly contribute to remote control accidents. The report identifies that these types of accidents commonly happen to experienced miners during routine mining activities, with the majority occurring while moving the miner from one face to another (place changing). Another common aspect of the accidents is that many of the victims are newly employed at the mine where the accident occurred. Training all employees to stay outside the turning radius of an energized remote control continuous miner, establishing this as a safe operating procedure, and consistently enforcing this practice among miners will reduce these types of accidents. 10 figs., 5 tabs., 7 apps.

  8. Temporal predictability enhances judgements of causality in elemental causal induction from both observation and intervention.

    PubMed

    Greville, W James; Buehner, Marc J

    2016-01-01

    When the temporal interval or delay separating cause and effect is consistent over repeated instances, it becomes possible to predict when the effect will follow from the cause, hence temporal predictability serves as an appropriate term for describing consistent cause-effect delays. It has been demonstrated that in instrumental action-outcome learning tasks, enhancing temporal predictability by holding the cause-effect interval constant elicits higher judgements of causality compared to conditions involving variable temporal intervals. Here, we examine whether temporal predictability exerts a similar influence when causal learning takes place through observation rather than intervention through instrumental action. Four experiments demonstrated that judgements of causality were higher when the temporal interval was constant than when it was variable, and that judgements declined with increasing variability. We further found that this beneficial effect of predictability was stronger in situations where the effect base-rate was zero (Experiments 1 and 3). The results therefore clearly indicate that temporal predictability enhances impressions of causality, and that this effect is robust and general. Factors that could mediate this effect are discussed.

  9. Visualization of Traffic Accidents

    NASA Technical Reports Server (NTRS)

    Wang, Jie; Shen, Yuzhong; Khattak, Asad

    2010-01-01

    Traffic accidents have tremendous impact on society. Annually approximately 6.4 million vehicle accidents are reported by police in the US and nearly half of them result in catastrophic injuries. Visualizations of traffic accidents using geographic information systems (GIS) greatly facilitate handling and analysis of traffic accidents in many aspects. Environmental Systems Research Institute (ESRI), Inc. is the world leader in GIS research and development. ArcGIS, a software package developed by ESRI, has the capabilities to display events associated with a road network, such as accident locations, and pavement quality. But when event locations related to a road network are processed, the existing algorithm used by ArcGIS does not utilize all the information related to the routes of the road network and produces erroneous visualization results of event locations. This software bug causes serious problems for applications in which accurate location information is critical for emergency responses, such as traffic accidents. This paper aims to address this problem and proposes an improved method that utilizes all relevant information of traffic accidents, namely, route number, direction, and mile post, and extracts correct event locations for accurate traffic accident visualization and analysis. The proposed method generates a new shape file for traffic accidents and displays them on top of the existing road network in ArcGIS. Visualization of traffic accidents along Hampton Roads Bridge Tunnel is included to demonstrate the effectiveness of the proposed method.

  10. Causal factors for seismicity near Azle, Texas

    PubMed Central

    Hornbach, Matthew J.; DeShon, Heather R.; Ellsworth, William L.; Stump, Brian W.; Hayward, Chris; Frohlich, Cliff; Oldham, Harrison R.; Olson, Jon E.; Magnani, M. Beatrice; Brokaw, Casey; Luetgert, James H.

    2015-01-01

    In November 2013, a series of earthquakes began along a mapped ancient fault system near Azle, Texas. Here we assess whether it is plausible that human activity caused these earthquakes. Analysis of both lake and groundwater variations near Azle shows that no significant stress changes were associated with the shallow water table before or during the earthquake sequence. In contrast, pore-pressure models demonstrate that a combination of brine production and wastewater injection near the fault generated subsurface pressures sufficient to induce earthquakes on near-critically stressed faults. On the basis of modelling results and the absence of historical earthquakes near Azle, brine production combined with wastewater disposal represent the most likely cause of recent seismicity near Azle. For assessing the earthquake cause, our research underscores the necessity of monitoring subsurface wastewater formation pressures and monitoring earthquakes having magnitudes of ∼M2 and greater. Currently, monitoring at these levels is not standard across Texas or the United States. PMID:25898170

  11. Causal reasoning with mental models

    PubMed Central

    Khemlani, Sangeet S.; Barbey, Aron K.; Johnson-Laird, Philip N.

    2014-01-01

    This paper outlines the model-based theory of causal reasoning. It postulates that the core meanings of causal assertions are deterministic and refer to temporally-ordered sets of possibilities: A causes B to occur means that given A, B occurs, whereas A enables B to occur means that given A, it is possible for B to occur. The paper shows how mental models represent such assertions, and how these models underlie deductive, inductive, and abductive reasoning yielding explanations. It reviews evidence both to corroborate the theory and to account for phenomena sometimes taken to be incompatible with it. Finally, it reviews neuroscience evidence indicating that mental models for causal inference are implemented within lateral prefrontal cortex. PMID:25389398

  12. Causal inference from observational data.

    PubMed

    Listl, Stefan; Jürges, Hendrik; Watt, Richard G

    2016-10-01

    Randomized controlled trials have long been considered the 'gold standard' for causal inference in clinical research. In the absence of randomized experiments, identification of reliable intervention points to improve oral health is often perceived as a challenge. But other fields of science, such as social science, have always been challenged by ethical constraints to conducting randomized controlled trials. Methods have been established to make causal inference using observational data, and these methods are becoming increasingly relevant in clinical medicine, health policy and public health research. This study provides an overview of state-of-the-art methods specifically designed for causal inference in observational data, including difference-in-differences (DiD) analyses, instrumental variables (IV), regression discontinuity designs (RDD) and fixed-effects panel data analysis. The described methods may be particularly useful in dental research, not least because of the increasing availability of routinely collected administrative data and electronic health records ('big data'). PMID:27111146

  13. Fluctuations in relativistic causal hydrodynamics

    NASA Astrophysics Data System (ADS)

    Kumar, Avdhesh; Bhatt, Jitesh R.; Mishra, Ananta P.

    2014-05-01

    Formalism to calculate the hydrodynamic fluctuations by applying the Onsager theory to the relativistic Navier-Stokes equation is already known. In this work, we calculate hydrodynamic fluctuations within the framework of the second order hydrodynamics of Müller, Israel and Stewart and its generalization to the third order. We have also calculated the fluctuations for several other causal hydrodynamical equations. We show that the form for the Onsager-coefficients and form of the correlation functions remain the same as those obtained by the relativistic Navier-Stokes equation and do not depend on any specific model of hydrodynamics. Further we numerically investigate evolution of the correlation function using the one dimensional boost-invariant (Bjorken) flow. We compare the correlation functions obtained using the causal hydrodynamics with the correlation function for the relativistic Navier-Stokes equation. We find that the qualitative behavior of the correlation functions remains the same for all the models of the causal hydrodynamics.

  14. Appropriate radiation accident medical management: necessity of extensive preparatory planning.

    PubMed

    Dörr, H D; Meineke, V

    2006-11-01

    Despite the rareness of radiation accidents, their potential consequences can be very serious, and appropriate medical management requires sufficient preparatory planning. To identify necessary factors for sufficient preparatory planning, three different radiation accidents were analyzed, i.e. the accidents in Goiânia, Brazil, 1987; Lilo, Georgia, 1997; and Tokai-mura, Japan, 1999. These radiation accidents have been chosen specifically because they provide a wide spectrum of potential radiation accident scenarios. After a brief description of the accidents and the following medical management, the measures taken are analyzed in terms of diagnosing radiation-induced health damage, determining the cause, dealing with contamination/incorporation, pathophysiological and therapeutic principles, preparatory planning, national and international cooperation and training. Several important factors are identified that should be considered in preparatory planning, i.e. preventing delayed diagnosis and training of medical personnel. Due to limited national resources, an intensified international cooperation to manage medical radiation accidents is of great importance.

  15. Reasoning about Causal Relationships: Inferences on Causal Networks

    PubMed Central

    Rottman, Benjamin Margolin; Hastie, Reid

    2013-01-01

    Over the last decade, a normative framework for making causal inferences, Bayesian Probabilistic Causal Networks, has come to dominate psychological studies of inference based on causal relationships. The following causal networks—[X→Y→Z, X←Y→Z, X→Y←Z]—supply answers for questions like, “Suppose both X and Y occur, what is the probability Z occurs?” or “Suppose you intervene and make Y occur, what is the probability Z occurs?” In this review, we provide a tutorial for how normatively to calculate these inferences. Then, we systematically detail the results of behavioral studies comparing human qualitative and quantitative judgments to the normative calculations for many network structures and for several types of inferences on those networks. Overall, when the normative calculations imply that an inference should increase, judgments usually go up; when calculations imply a decrease, judgments usually go down. However, two systematic deviations appear. First, people’s inferences violate the Markov assumption. For example, when inferring Z from the structure X→Y→Z, people think that X is relevant even when Y completely mediates the relationship between X and Z. Second, even when people’s inferences are directionally consistent with the normative calculations, they are often not as sensitive to the parameters and the structure of the network as they should be. We conclude with a discussion of productive directions for future research. PMID:23544658

  16. Analysis of surface powered haulage accidents, January 1990--July 1996

    SciTech Connect

    Fesak, G.M.; Breland, R.M.; Spadaro, J.

    1996-12-31

    This report addresses surface haulage accidents that occurred between January 1990 and July 1996 involving haulage trucks (including over-the-road trucks), front-end-loaders, scrapers, utility trucks, water trucks, and other mobile haulage equipment. The study includes quarries, open pits and surface coal mines utilizing self-propelled mobile equipment to transport personnel, supplies, rock, overburden material, ore, mine waste, or coal for processing. A total of 4,397 accidents were considered. This report summarizes the major factors that led to the accidents and recommends accident prevention methods to reduce the frequency of these accidents.

  17. Laser accidents: Being Prepared

    SciTech Connect

    Barat, K

    2003-01-24

    The goal of the Laser Safety Officer and any laser safety program is to prevent a laser accident from occurring, in particular an injury to a person's eyes. Most laser safety courses talk about laser accidents, causes, and types of injury. The purpose of this presentation is to present a plan for safety offices and users to follow in case of accident or injury from laser radiation.

  18. [Cerebral vascular accidents in French Polynesia].

    PubMed

    Gras, C; Papouin, G; Prigent, D; Beaugendre, E; Lionet, P; Brodin, S; Legall, R; Marjou, F; Spiegel, A; Gendron, Y

    1992-01-01

    The authors report on the results of a survey on cardiovascular accidents hospitalized between 01 April 1990 and 31 January 1991 carried out in the Services of Medicine and Cardiology in the Territorial Hospital Center of Papeete. This survey was: 56 cardiovascular accidents: 1/4 (hemorrhagic and 3/4 (42) ischemic. Mean age 59 (extremes 23-86). 36 males (64%); 20 females (36%). 50 Polynesians; 6 Chinese people. Among the risk factors recorded, 38 (68%) were hypertensed patients; 17 (30%) were due to tabagism and 15 (25%) to diabetes; 3 (5%) are known to be carriers of a hypercholesterolemia. 59% of the patients had no case history; 25% the cardiovascular accidents have been observed in patients with cardiopathy; 12.5% are recurrent cardiovascular accidents. Clinically, 5 transient ischemic accidents (12%) out of 42 cardiovascular ischemic accidents. High arterial tension was recognized in 12/14 (86%) of hemorrhagic cardiovascular accidents and in 26/42 (62%) of ischemic cardiovascular accidents. In 42 ischemic cardiovascular accidents, 31 patients suffered from cardiopathy (74%) of which 15 (36%) presented an embolic cardiopathy. Interest of echography and electrocardiogram are discussed. Ultrasonic exam of carotid vessels was found abnormal in almost half of the cases when utilized (12/26). Finally, etiological diagnosis was certain in 17 cases, of presumption in 16 cases, and in 9 cases, it was not possible to precise any cardiovascular etiology. Tomodensitometric tests are discussed. 86% of the ischemic cardiovascular accident were treated with anticoagulants/thrombocyte antiagglutination. 24% of the patients died, 50% recovered incompletely and 26% completely. PMID:1602953

  19. The role of activity in visual impressions of causality.

    PubMed

    White, Peter A

    2006-01-01

    Phenomenal causality is an illusion built on an incomplete perception. It is an illusion because we can have visual impressions of causality when no interaction between objects is actually taking place. It is an illusion built on an incomplete perception because causality as we understand it neglects some factors involved in objective descriptions of interactions between objects in terms of the laws of mechanics. So, why don't we perceive object interactions in accordance with the laws of mechanics? I first consider what kinds of things can and cannot be causes perceptually, arguing that active objects can be causes and non-moving objects cannot be. Then, I argue that causal understanding originates with what we have the most direct experience of, our own actions on objects, and extends out from this point of origin to other domains of causality by a form of schema matching the interpretation of stimulus input by matching to abstracted stored representations of experiences. Schema matching raises the possibility of many more kinds of phenomenal causality than have hitherto been considered, and I conclude by suggesting some possibilities.

  20. Hindsight bias and causal reasoning: a minimalist approach.

    PubMed

    Yopchick, Jennelle E; Kim, Nancy S

    2012-02-01

    What factors contribute to hindsight bias, the phenomenon whereby the known outcome of an event appears obvious only after the fact? The Causal Model Theory (CMT) of hindsight bias (Nestler et al. in Soc Psychol 39:182-188, 2008a; in J Expl Psychol: Learn Mem Cog 34:1043-1054, 2008b; Pezzo in Mem 11:421-441, 2003; Wasserman et al. in Pers Soc Psychol Bull 17:30-35, 1991) posits that hindsight bias can occur when people have the opportunity to identify potential causal antecedents and evaluate whether they could have led to the outcome. Two experiments incorporating highly controlled minimalist scenarios supported the CMT. As predicted by the CMT, hindsight bias occurred when the causal factor explained the actual outcome better than the alternative outcome, and reverse hindsight bias occurred when the causal factor explained the alternative outcome better than the actual outcome. Moreover, we found new evidence that outcome knowledge alone was insufficient to elicit hindsight bias in the absence of a potential causal antecedent. Implications for future directions in hindsight bias research are discussed.

  1. Learning a Theory of Causality

    ERIC Educational Resources Information Center

    Goodman, Noah D.; Ullman, Tomer D.; Tenenbaum, Joshua B.

    2011-01-01

    The very early appearance of abstract knowledge is often taken as evidence for innateness. We explore the relative learning speeds of abstract and specific knowledge within a Bayesian framework and the role for innate structure. We focus on knowledge about causality, seen as a domain-general intuitive theory, and ask whether this knowledge can be…

  2. Nonlinear connectivity by Granger causality.

    PubMed

    Marinazzo, Daniele; Liao, Wei; Chen, Huafu; Stramaglia, Sebastiano

    2011-09-15

    The communication among neuronal populations, reflected by transient synchronous activity, is the mechanism underlying the information processing in the brain. Although it is widely assumed that the interactions among those populations (i.e. functional connectivity) are highly nonlinear, the amount of nonlinear information transmission and its functional roles are not clear. The state of the art to understand the communication between brain systems are dynamic causal modeling (DCM) and Granger causality. While DCM models nonlinear couplings, Granger causality, which constitutes a major tool to reveal effective connectivity, and is widely used to analyze EEG/MEG data as well as fMRI signals, is usually applied in its linear version. In order to capture nonlinear interactions between even short and noisy time series, a few approaches have been proposed. We review them and focus on a recently proposed flexible approach has been recently proposed, consisting in the kernel version of Granger causality. We show the application of the proposed approach on EEG signals and fMRI data.

  3. Identity, causality, and pronoun ambiguity.

    PubMed

    Sagi, Eyal; Rips, Lance J

    2014-10-01

    This article looks at the way people determine the antecedent of a pronoun in sentence pairs, such as: Albert invited Ron to dinner. He spent hours cleaning the house. The experiment reported here is motivated by the idea that such judgments depend on reasoning about identity (e.g., the identity of the he who cleaned the house). Because the identity of an individual over time depends on the causal-historical path connecting the stages of the individual, the correct antecedent will also depend on causal connections. The experiment varied how likely it is that the event of the first sentence (e.g., the invitation) would cause the event of the second (the house cleaning) for each of the two individuals (the likelihood that if Albert invited Ron to dinner, this would cause Albert to clean the house, versus cause Ron to clean the house). Decisions about the antecedent followed causal likelihood. A mathematical model of causal identity accounted for most of the key aspects of the data from the individual sentence pairs.

  4. Causal Inference for a Population of Causally Connected Units

    PubMed Central

    van der Laan, Mark J.

    2015-01-01

    Suppose that we observe a population of causally connected units. On each unit at each time-point on a grid we observe a set of other units the unit is potentially connected with, and a unit-specific longitudinal data structure consisting of baseline and time-dependent covariates, a time-dependent treatment, and a final outcome of interest. The target quantity of interest is defined as the mean outcome for this group of units if the exposures of the units would be probabilistically assigned according to a known specified mechanism, where the latter is called a stochastic intervention. Causal effects of interest are defined as contrasts of the mean of the unit-specific outcomes under different stochastic interventions one wishes to evaluate. This covers a large range of estimation problems from independent units, independent clusters of units, and a single cluster of units in which each unit has a limited number of connections to other units. The allowed dependence includes treatment allocation in response to data on multiple units and so called causal interference as special cases. We present a few motivating classes of examples, propose a structural causal model, define the desired causal quantities, address the identification of these quantities from the observed data, and define maximum likelihood based estimators based on cross-validation. In particular, we present maximum likelihood based super-learning for this network data. Nonetheless, such smoothed/regularized maximum likelihood estimators are not targeted and will thereby be overly bias w.r.t. the target parameter, and, as a consequence, generally not result in asymptotically normally distributed estimators of the statistical target parameter. To formally develop estimation theory, we focus on the simpler case in which the longitudinal data structure is a point-treatment data structure. We formulate a novel targeted maximum likelihood estimator of this estimand and show that the double robustness of the

  5. Entanglement, holography and causal diamonds

    NASA Astrophysics Data System (ADS)

    de Boer, Jan; Haehl, Felix M.; Heller, Michal P.; Myers, Robert C.

    2016-08-01

    We argue that the degrees of freedom in a d-dimensional CFT can be reorganized in an insightful way by studying observables on the moduli space of causal diamonds (or equivalently, the space of pairs of timelike separated points). This 2 d-dimensional space naturally captures some of the fundamental nonlocality and causal structure inherent in the entanglement of CFT states. For any primary CFT operator, we construct an observable on this space, which is defined by smearing the associated one-point function over causal diamonds. Known examples of such quantities are the entanglement entropy of vacuum excitations and its higher spin generalizations. We show that in holographic CFTs, these observables are given by suitably defined integrals of dual bulk fields over the corresponding Ryu-Takayanagi minimal surfaces. Furthermore, we explain connections to the operator product expansion and the first law of entanglemententropy from this unifying point of view. We demonstrate that for small perturbations of the vacuum, our observables obey linear two-derivative equations of motion on the space of causal diamonds. In two dimensions, the latter is given by a product of two copies of a two-dimensional de Sitter space. For a class of universal states, we show that the entanglement entropy and its spin-three generalization obey nonlinear equations of motion with local interactions on this moduli space, which can be identified with Liouville and Toda equations, respectively. This suggests the possibility of extending the definition of our new observables beyond the linear level more generally and in such a way that they give rise to new dynamically interacting theories on the moduli space of causal diamonds. Various challenges one has to face in order to implement this idea are discussed.

  6. Childhood accidents: epidemiology, trends, and prevention.

    PubMed Central

    Kemp, A; Sibert, J

    1997-01-01

    Accidents are the most common cause of death in children over one year of age. Prevention remains a high priority. We have reviewed the current epidemiology of childhood accidents and their prevention, and made recommendations for the future. In 1992, 559 children died in United Kingdom as a result of an accidents--240 from road traffic accidents and 100 from burns and scalds. Every year 50 children drown. Accidents cause significant disability to children. Many children, up to one in four of the population in urban areas, attend accident and emergency departments, and 5-10% of these are admitted to hospital. Accident risk factors include low social class, psychosocial stress, an unsafe environment, and child developmental disorders. Research has shown that prevention is best achieved by making the child's environment safer, often through legislation. Insufficient resources have been put into both research into childhood injuries and preventive work in communities. Collaboration between health authorities, NHS trusts, local authorities and community networks is vital if success is to be achieved. A national safety agenda for children would focus the attention that this problem deserves. PMID:9315935

  7. Civil aircraft accident investigation.

    PubMed

    Haines, Daniel

    2013-01-01

    This talk reviews some historic aircraft accidents and some more recent. It reflects on the division of accident causes, considering mechanical failures and aircrew failures, and on aircrew training. Investigation results may lead to improved aircraft design, and to appropriate crew training. PMID:24057309

  8. Farm accidents in children.

    PubMed Central

    Cameron, D.; Bishop, C.; Sibert, J. R.

    1992-01-01

    OBJECTIVE--To examine the problem of accidental injury to children on farms. DESIGN--Prospective county based study of children presenting to accident and emergency departments over 12 months with injuries sustained in a farm setting and nationwide review of fatal childhood farm accidents over the four years April 1986 to March 1990. SETTING--Accident and emergency departments in Aberystwyth, Carmarthen, Haverfordwest, and Llanelli and fatal accidents in England, Scotland, and Wales notified to the Health and Safety Executive register. SUBJECTS--Children aged under 16. MAIN OUTCOME MEASURE--Death or injury after farm related accidents. RESULTS--65 accidents were recorded, including 18 fractures. Nine accidents necessitated admission to hospital for a mean of two (range one to four) days. 13 incidents were related to tractors and other machinery; 24 were due to falls. None of these incidents were reported under the statutory notification scheme. 33 deaths were notified, eight related to tractors and allied machinery and 10 related to falling objects. CONCLUSIONS--Although safety is improving, the farm remains a dangerous environment for children. Enforcement of existing safety legislation with significant penalties and targeting of safety education will help reduce accident rates further. PMID:1638192

  9. Effect of measurement noise on Granger causality.

    PubMed

    Nalatore, Hariharan; Sasikumar, N; Rangarajan, Govindan

    2014-12-01

    Most of the signals recorded in experiments are inevitably contaminated by measurement noise. Hence, it is important to understand the effect of such noise on estimating causal relations between such signals. A primary tool for estimating causality is Granger causality. Granger causality can be computed by modeling the signal using a bivariate autoregressive (AR) process. In this paper, we greatly extend the previous analysis of the effect of noise by considering a bivariate AR process of general order p. From this analysis, we analytically obtain the dependence of Granger causality on various noise-dependent system parameters. In particular, we show that measurement noise can lead to spurious Granger causality and can suppress true Granger causality. These results are verified numerically. Finally, we show how true causality can be recovered numerically using the Kalman expectation maximization algorithm.

  10. Critical factors and paths influencing construction workers' safety risk tolerances.

    PubMed

    Wang, Jiayuan; Zou, Patrick X W; Li, Penny P

    2016-08-01

    While workers' safety risk tolerances have been regarded as a main reason for their unsafe behaviors, little is known about why different people have different risk tolerances even when confronting the same situation. The aim of this research is to identify the critical factors and paths that influence workers' safety risk tolerance and to explore how they contribute to accident causal model from a system thinking perceptive. A number of methods were carried out to analyze the data collected through interviews and questionnaire surveys. In the first and second steps of the research, factor identification, factor ranking and factor analysis were carried out, and the results show that workers' safety risk tolerance can be influenced by four groups of factors, namely: (1) personal subjective perception; (2) work knowledge and experiences; (3) work characteristics; and (4) safety management. In the third step of the research, hypothetical influencing path model was developed and tested by using structural equation modeling (SEM). It is found that the effects of external factors (safety management and work characteristics) on risk tolerance are larger than that of internal factors (personal subjective perception and work knowledge & experiences). Specifically, safety management contributes the most to workers' safety risk tolerance through its direct effect and indirect effect; while personal subjective perception comes the second and can act as an intermedia for work characteristics. This research provides an in-depth insight of workers' unsafe behaviors by depicting the contributing factors as shown in the accident causal model developed in this research. PMID:26775077

  11. Critical factors and paths influencing construction workers' safety risk tolerances.

    PubMed

    Wang, Jiayuan; Zou, Patrick X W; Li, Penny P

    2016-08-01

    While workers' safety risk tolerances have been regarded as a main reason for their unsafe behaviors, little is known about why different people have different risk tolerances even when confronting the same situation. The aim of this research is to identify the critical factors and paths that influence workers' safety risk tolerance and to explore how they contribute to accident causal model from a system thinking perceptive. A number of methods were carried out to analyze the data collected through interviews and questionnaire surveys. In the first and second steps of the research, factor identification, factor ranking and factor analysis were carried out, and the results show that workers' safety risk tolerance can be influenced by four groups of factors, namely: (1) personal subjective perception; (2) work knowledge and experiences; (3) work characteristics; and (4) safety management. In the third step of the research, hypothetical influencing path model was developed and tested by using structural equation modeling (SEM). It is found that the effects of external factors (safety management and work characteristics) on risk tolerance are larger than that of internal factors (personal subjective perception and work knowledge & experiences). Specifically, safety management contributes the most to workers' safety risk tolerance through its direct effect and indirect effect; while personal subjective perception comes the second and can act as an intermedia for work characteristics. This research provides an in-depth insight of workers' unsafe behaviors by depicting the contributing factors as shown in the accident causal model developed in this research.

  12. Constraints on Children's Judgments of Magical Causality

    ERIC Educational Resources Information Center

    Woolley, Jacqueline D.; Browne, Cheryl A.; Boerger, Elizabeth A.

    2006-01-01

    In 3 studies we addressed the operation of constraints on children's causal judgments. Our primary focus was whether children's beliefs about magical causality, specifically wishing, are constrained by features that govern the attribution of ordinary causality. In Experiment 1, children witnessed situations in which a confederate's wish appeared…

  13. Expectations and interpretations during causal learning.

    PubMed

    Luhmann, Christian C; Ahn, Woo-Kyoung

    2011-05-01

    In existing models of causal induction, 4 types of covariation information (i.e., presence/absence of an event followed by presence/absence of another event) always exert identical influences on causal strength judgments (e.g., joint presence of events always suggests a generative causal relationship). In contrast, we suggest that, due to expectations developed during causal learning, learners give varied interpretations to covariation information as it is encountered and that these interpretations influence the resulting causal beliefs. In Experiments 1A-1C, participants' interpretations of observations during a causal learning task were dynamic, expectation based, and, furthermore, strongly tied to subsequent causal judgments. Experiment 2 demonstrated that adding trials of joint absence or joint presence of events, whose roles have been traditionally interpreted as increasing causal strengths, could result in decreased overall causal judgments and that adding trials where one event occurs in the absence of another, whose roles have been traditionally interpreted as decreasing causal strengths, could result in increased overall causal judgments. We discuss implications for traditional models of causal learning and how a more top-down approach (e.g., Bayesian) would be more compatible with the current findings.

  14. Expectations and Interpretations during Causal Learning

    ERIC Educational Resources Information Center

    Luhmann, Christian C.; Ahn, Woo-kyoung

    2011-01-01

    In existing models of causal induction, 4 types of covariation information (i.e., presence/absence of an event followed by presence/absence of another event) always exert identical influences on causal strength judgments (e.g., joint presence of events always suggests a generative causal relationship). In contrast, we suggest that, due to…

  15. Expectations and Interpretations During Causal Learning

    PubMed Central

    Luhmann, Christian C.; Ahn, Woo-kyoung

    2012-01-01

    In existing models of causal induction, 4 types of covariation information (i.e., presence/absence of an event followed by presence/absence of another event) always exert identical influences on causal strength judgments (e.g., joint presence of events always suggests a generative causal relationship). In contrast, we suggest that, due to expectations developed during causal learning, learners give varied interpretations to covariation information as it is encountered and that these interpretations influence the resulting causal beliefs. In Experiments 1A–1C, participants’ interpretations of observations during a causal learning task were dynamic, expectation based, and, furthermore, strongly tied to subsequent causal judgments. Experiment 2 demonstrated that adding trials of joint absence or joint presence of events, whose roles have been traditionally interpreted as increasing causal strengths, could result in decreased overall causal judgments and that adding trials where one event occurs in the absence of another, whose roles have been traditionally interpreted as decreasing causal strengths, could result in increased overall causal judgments. We discuss implications for traditional models of causal learning and how a more top-down approach (e.g., Bayesian) would be more compatible with the current findings. PMID:21534705

  16. Designing Effective Supports for Causal Reasoning

    ERIC Educational Resources Information Center

    Jonassen, David H.; Ionas, Ioan Gelu

    2008-01-01

    Causal reasoning represents one of the most basic and important cognitive processes that underpin all higher-order activities, such as conceptual understanding and problem solving. Hume called causality the "cement of the universe" [Hume (1739/2000). Causal reasoning is required for making predictions, drawing implications and inferences, and…

  17. Exploring Individual Differences in Preschoolers' Causal Stance

    ERIC Educational Resources Information Center

    Alvarez, Aubry; Booth, Amy E.

    2016-01-01

    Preschoolers, as a group, are highly attuned to causality, and this attunement is known to facilitate memory, learning, and problem solving. However, recent work reveals substantial individual variability in the strength of children's "causal stance," as demonstrated by their curiosity about and preference for new causal information. In…

  18. Representing Personal Determinants in Causal Structures.

    ERIC Educational Resources Information Center

    Bandura, Albert

    1984-01-01

    Responds to Staddon's critique of the author's earlier article and addresses issues raised by Staddon's (1984) alternative models of causality. The author argues that it is not the formalizability of causal processes that is the issue but whether cognitive determinants of behavior are reducible to past stimulus inputs in causal structures.…

  19. Causal inference in economics and marketing.

    PubMed

    Varian, Hal R

    2016-07-01

    This is an elementary introduction to causal inference in economics written for readers familiar with machine learning methods. The critical step in any causal analysis is estimating the counterfactual-a prediction of what would have happened in the absence of the treatment. The powerful techniques used in machine learning may be useful for developing better estimates of the counterfactual, potentially improving causal inference.

  20. Safety analysis of surface haulage accidents

    SciTech Connect

    Randolph, R.F.; Boldt, C.M.K.

    1996-12-31

    Research on improving haulage truck safety, started by the U.S. Bureau of Mines, is being continued by its successors. This paper reports the orientation of the renewed research efforts, beginning with an update on accident data analysis, the role of multiple causes in these accidents, and the search for practical methods for addressing the most important causes. Fatal haulage accidents most often involve loss of control or collisions caused by a variety of factors. Lost-time injuries most often involve sprains or strains to the back or multiple body areas, which can often be attributed to rough roads and the shocks of loading and unloading. Research to reduce these accidents includes improved warning systems, shock isolation for drivers, encouraging seatbelt usage, and general improvements to system and task design.

  1. Modeling of causality with metamaterials

    NASA Astrophysics Data System (ADS)

    Smolyaninov, Igor I.

    2013-02-01

    Hyperbolic metamaterials may be used to model a 2 + 1-dimensional Minkowski space-time in which the role of time is played by one of the spatial coordinates. When a metamaterial is built and illuminated with a coherent extraordinary laser beam, the stationary pattern of light propagation inside the metamaterial may be treated as a collection of particle world lines, which represents a complete ‘history’ of this 2 + 1-dimensional space-time. While this model may be used to build interesting space-time analogs, such as metamaterial ‘black holes’ and a metamaterial ‘big bang’, it lacks causality: since light inside the metamaterial may propagate back and forth along the ‘timelike’ spatial coordinate, events in the ‘future’ may affect events in the ‘past’. Here we demonstrate that a more sophisticated metamaterial model may fix this deficiency via breaking the mirror and temporal (PT) symmetries of the original model and producing one-way propagation along the ‘timelike’ spatial coordinate. The resulting 2 + 1-dimensional Minkowski space-time appears to be causal. This scenario may be considered as a metamaterial model of the Wheeler-Feynman absorber theory of causality.

  2. Velocity Requirements for Causality Violation

    NASA Astrophysics Data System (ADS)

    Modanese, Giovanni

    We re-examine the "Regge-Tolman paradox" with reference to some recent experimental results. It is straightforward to find a formula for the velocity v of the moving system required to produce causality violation. This formula typically yields a velocity very close to the speed of light (for instance, v/c > 0.97 for X-shaped microwaves), which raises some doubts about the real physical observability of the violations. We then compute the velocity requirement introducing a delay between the reception of the primary signal and the emission of the secondary. It turns out that in principle for any delay it is possible to find moving observers able to produce active causal violation. This is mathematically due to the singularity of the Lorentz transformations for β →1. For a realistic delay due to the propagation of a luminal precursor, we find that causality violations in the reported experiments are still more unlikely (v/c > 0.989), and even in the hypothesis that the superluminal propagation velocity goes to infinity, the velocity requirement is bounded by v/c > 0.62. We also prove that if two oscopic bodies exchange energy and momentum through superluminal signals, then the swap of signal source and target is incompatible with the Lorentz transformations; therefore it is not possible to distinguish between source and target, even with reference to a definite reference frame.

  3. [The application of causal diagrams to conceptualize mechanisms in occupational epidemiology].

    PubMed

    Sánchez-Niubò, Albert; Forero, Carlos G; Benavides, Fernando G

    2016-01-01

    Although a goal of epidemiological research is to identify causal relationships between a risk factor and a health problem, the methodology employed often sacrifices internal validity to gain capacity to detect associations. There are new graphical and statistical methods that can help unravel the possible causal mechanisms and better understand this "black box". This paper presents causal diagrams, one of the most useful tools for mapping out, prior to analysis, whether a possible association is causal or just due to bias. To demonstrate its usefulness, we use occupational health examples, showing how associations may arise through non-causal pathways as a result of bias. In conclusion, we recommend the routine practice of using causal diagrams in epidemiological research.

  4. Persistence of airline accidents.

    PubMed

    Barros, Carlos Pestana; Faria, Joao Ricardo; Gil-Alana, Luis Alberiko

    2010-10-01

    This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non-stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long-run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation.

  5. Development and Coherence of Beliefs Regarding Disease Causality and Prevention

    ERIC Educational Resources Information Center

    Sigelman, Carol K.

    2014-01-01

    Guided by a naïve theories perspective on the development of thinking about disease, this study of 188 children aged 6 to 18 examined knowledge of HIV/AIDS causality and prevention using parallel measures derived from open-ended and structured interviews. Knowledge of both risk factors and prevention rules, as well as conceptual understanding of…

  6. Mendelian randomisation: a tool for assessing causality in observational epidemiology.

    PubMed

    Sheehan, Nuala A; Meng, Sha; Didelez, Vanessa

    2011-01-01

    Detection and assessment of the effect of a modifiable risk factor on a disease with view to informing public health intervention policies are of fundamental concern in aetiological epidemiology. In order to have solid evidence that such a public health intervention has the desired effect, it is necessary to ascertain that an observed association or correlation between a risk factor and a disease means that the risk factor is causal for the disease. Inferring causality from observational data is difficult, typically due to confounding by social, behavioural, or physiological factors which are difficult to control for and particularly difficult to measure accurately. A possible approach to inferring causality when confounding is believed to be present but unobservable, as it may not even be fully understood, is based on the method of instrumental variables and is known under the name of Mendelian randomisation if the instrument is a genetic variant. While testing for the presence of a causal effect using this method is generally straightforward, point estimates of such an effect are only obtainable under additional parametric assumptions. This chapter introduces the concept and illustrates the method and its assumptions with simple real-life examples. It concludes with a brief discussion on pitfalls and limitations.

  7. Causal Attributions and Recovery from Rape: Implications for Counseling.

    ERIC Educational Resources Information Center

    Frazier, Patricia A.; Schauben, Laura J.

    One factor related to postrape trauma is the survivor's belief about the cause of the rape. Most research to date on the relation between causal attributions and postrape recovery has been guided by a theoretical model which proposes that certain types of self-blame can be adaptive for survivors. Specifically, behavioral self-blame is thought to…

  8. Targeted Maximum Likelihood Based Causal Inference: Part I

    PubMed Central

    van der Laan, Mark J.

    2010-01-01

    Given causal graph assumptions, intervention-specific counterfactual distributions of the data can be defined by the so called G-computation formula, which is obtained by carrying out these interventions on the likelihood of the data factorized according to the causal graph. The obtained G-computation formula represents the counterfactual distribution the data would have had if this intervention would have been enforced on the system generating the data. A causal effect of interest can now be defined as some difference between these counterfactual distributions indexed by different interventions. For example, the interventions can represent static treatment regimens or individualized treatment rules that assign treatment in response to time-dependent covariates, and the causal effects could be defined in terms of features of the mean of the treatment-regimen specific counterfactual outcome of interest as a function of the corresponding treatment regimens. Such features could be defined nonparametrically in terms of so called (nonparametric) marginal structural models for static or individualized treatment rules, whose parameters can be thought of as (smooth) summary measures of differences between the treatment regimen specific counterfactual distributions. In this article, we develop a particular targeted maximum likelihood estimator of causal effects of multiple time point interventions. This involves the use of loss-based super-learning to obtain an initial estimate of the unknown factors of the G-computation formula, and subsequently, applying a target-parameter specific optimal fluctuation function (least favorable parametric submodel) to each estimated factor, estimating the fluctuation parameter(s) with maximum likelihood estimation, and iterating this updating step of the initial factor till convergence. This iterative targeted maximum likelihood updating step makes the resulting estimator of the causal effect double robust in the sense that it is

  9. Comparative performance evaluation of data-driven causality measures applied to brain networks.

    PubMed

    Fasoula, Angie; Attal, Yohan; Schwartz, Denis

    2013-05-15

    In this article, several well-known data-driven causality methods are revisited and comparatively evaluated. These are the Granger-Geweke Causality (GGC), the Partial Directed Coherence (PDC), the Directed Transfer Function (DTF) and the Direct Directed Transfer Function (dDTF). The robustness of the four causality measures against two degradation factors is quantitatively evaluated. These are: the presence of realistic biological/electronic noise at various SNR levels, as recorded on a MagnetoEncephalography (MEG) machine, and the presence of a weak node in the brain network where the causality analysis is applied. The causality measures are evaluated in terms of the relative estimation error and the compromise between true and fictitious causal density in the brain network. Both parametric and non-parametric causality analysis is performed. It is illustrated that the non-parametric method is a promising alternative to the more commonly applied MVAR-model based causality analysis. It is also demonstrated that, in the presence of both tested degradation factors, the DTF method is the most robust in terms of low estimation error, while the PDC in terms of low fictitious causal density. The dDTF provides lower fictitious causal density and higher spectral selectivity as compared to DTF, at high enough SNR. The GGC exhibits the worst compromise of performance. An application of the causality measures to a set of MEG resting-state experimental data is accordingly presented. It is demonstrated that significant contrast between the Eyes-Closed and Eyes-Open rest condition in the alpha frequency band allows to detect significant causality between the occipital cortex and the thalamus.

  10. Causal Inference and Observational Research: The Utility of Twins

    PubMed Central

    McGue, Matt; Osler, Merete; Christensen, Kaare

    2011-01-01

    Valid causal inference is central to progress in theoretical and applied psychology. Although the randomized experiment is widely considered the gold standard for determining whether a given exposure increases the likelihood of some specified outcome, experiments are not always feasible and in some cases can result in biased estimates of causal effects. Alternatively, standard observational approaches are limited by the possibility of confounding, reverse causation, and the nonrandom distribution of exposure (i.e., selection). We describe the counterfactual model of causation and apply it to the challenges of causal inference in observational research, with a particular focus on aging. We argue that the study of twin pairs discordant on exposure, and in particular discordant monozygotic twins, provides a useful analog to the idealized counterfactual design. A review of discordant-twin studies in aging reveals that they are consistent with, but do not unambiguously establish, a causal effect of lifestyle factors on important late-life outcomes. Nonetheless, the existing studies are few in number and have clear limitations that have not always been considered in interpreting their results. It is concluded that twin researchers could make greater use of the discordant-twin design as one approach to strengthen causal inferences in observational research. PMID:21593989

  11. Improving causality induction with category learning.

    PubMed

    Guo, Yi; Wang, Zhihong; Shao, Zhiqing

    2014-01-01

    Causal relations are of fundamental importance for human perception and reasoning. According to the nature of causality, causality has explicit and implicit forms. In the case of explicit form, causal-effect relations exist at either clausal or discourse levels. The implicit causal-effect relations heavily rely on empirical analysis and evidence accumulation. This paper proposes a comprehensive causality extraction system (CL-CIS) integrated with the means of category-learning. CL-CIS considers cause-effect relations in both explicit and implicit forms and especially practices the relation between category and causality in computation. In elaborately designed experiments, CL-CIS is evaluated together with general causality analysis system (GCAS) and general causality analysis system with learning (GCAS-L), and it testified to its own capability and performance in construction of cause-effect relations. This paper confirms the expectation that the precision and coverage of causality induction can be remarkably improved by means of causal and category learning.

  12. Improving Causality Induction with Category Learning

    PubMed Central

    Wang, Zhihong; Shao, Zhiqing

    2014-01-01

    Causal relations are of fundamental importance for human perception and reasoning. According to the nature of causality, causality has explicit and implicit forms. In the case of explicit form, causal-effect relations exist at either clausal or discourse levels. The implicit causal-effect relations heavily rely on empirical analysis and evidence accumulation. This paper proposes a comprehensive causality extraction system (CL-CIS) integrated with the means of category-learning. CL-CIS considers cause-effect relations in both explicit and implicit forms and especially practices the relation between category and causality in computation. In elaborately designed experiments, CL-CIS is evaluated together with general causality analysis system (GCAS) and general causality analysis system with learning (GCAS-L), and it testified to its own capability and performance in construction of cause-effect relations. This paper confirms the expectation that the precision and coverage of causality induction can be remarkably improved by means of causal and category learning. PMID:24883419

  13. A review of causal inference for biomedical informatics

    PubMed Central

    Kleinberg, Samantha; Hripcsak, George

    2011-01-01

    Causality is an important concept throughout the health sciences and is particularly vital for informatics work such as finding adverse drug events or risk factors for disease using electronic health records. While philosophers and scientists working for centuries on formalizing what makes something a cause have not reached a consensus, new methods for inference show that we can make progress in this area in many practical cases. This article reviews core concepts in understanding and identifying causality and then reviews current computational methods for inference and explanation, focusing on inference from large-scale observational data. While the problem is not fully solved, we show that graphical models and Granger causality provide useful frameworks for inference and that a more recent approach based on temporal logic addresses some of the limitations of these methods. PMID:21782035

  14. Voluntary action and causality in temporal binding.

    PubMed

    Cravo, Andre M; Claessens, Peter M E; Baldo, Marcus V C

    2009-10-01

    Previous studies have documented temporal attraction in perceived times of actions and their effects. While some authors argue that voluntary action is a necessary condition for this phenomenon, others claim that the causal relationship between action and effect is the crucial ingredient. In the present study, we investigate voluntary action and causality as the necessary and sufficient conditions for temporal binding. We used a variation of the launching effect proposed by Michotte, in which participants controlled the launch stimulus in some blocks. Volunteers reported causality ratings and estimated the interval between the two events. Our results show dissociations between causality ratings and temporal estimation. While causality ratings are not affected by voluntary action, temporal bindings were only found in the presence of both voluntary action and high causality. Our results indicate that voluntary action and causality are both necessary for the emergence of temporal binding.

  15. Longitudinal relationship between economic development and occupational accidents in China.

    PubMed

    Song, Li; He, Xueqiu; Li, Chengwu

    2011-01-01

    The relativity between economic development and occupational accidents is a debated topic. Compared with the development courses of both economic development and occupational accidents in China during 1953-2008, this paper used statistic methods such as Granger causality test, cointegration test and impulse response function based on the vector autoregression model to investigate the relativity between economic development and occupational accidents in China from 1953 to 2008. Owing to fluctuation and growth scale characteristics of economic development, two dimensions including economic cycle and economic scale were divided. Results showed that there was no relationship between occupational accidents and economic scale during 1953-1978. Fatality rate per 10(5) workers was a conductive variable to gross domestic product per capita during 1979-2008. And economic cycle was an indicator to occupational accidents during 1979-2008. Variation of economic speed had important influence on occupational accidents in short term. Thus it is necessary to adjust Chinese occupational safety policy according to tempo variation of economic growth.

  16. Accident resistant transport container

    DOEpatents

    Anderson, J.A.; Cole, K.K.

    The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

  17. Accident resistant transport container

    DOEpatents

    Andersen, John A.; Cole, James K.

    1980-01-01

    The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

  18. Safety Is No Accident.

    ERIC Educational Resources Information Center

    Christiansen, Monty L.

    1985-01-01

    Liability suits involving accidents in park and recreation areas are expensive and intangible costs are incalculable. Risk management practices related to park planning, personnel, and administrative practices are discussed. (MT)

  19. Saliva alcohol concentrations in accident and emergency attendances

    PubMed Central

    Simpson, T; Murphy, N; Peck, D

    2001-01-01

    Objectives—Although alcohol is known to play a key part in accidents, no UK study has assessed alcohol concentrations in a comprehensive sample of accident and emergency (A&E) attenders. This study set out to do this, and examine the relation between alcohol concentrations and the severity, type and circumstances of presentation, and the sociodemographic characteristics of patients. Methods—A survey was conducted of all new A&E attenders (aged 10 years or over). Two 24 hour periods for each day of the week were covered in 6, 7 or 11 hour sessions over a two month period. Alcohol concentrations were assessed from saliva samples using a disposable device. Data were collected from 638 attenders, of whom 544 provided saliva samples; the remainder refused or were unable to participate. Results—Positive saliva alcohol readings were obtained in 22% of attenders (95%CI 19% to 26%); this increased to 25% if others were included (for example, those who refused to participate but were judged to be intoxicated). Alcohol was associated with 94% of incidents of self harm, 54% of non-specific/multiple complaints, 47% of collapses, 50% of assaults, and 50% of patients admitted to hospital. Higher concentrations of alcohol were found from Friday to Sunday, between midnight and 0900, and in patients aged 41 to 60. Among people with positive alcohol results, those attending with a companion had higher concentrations than those attending alone. There were no significant differences between men and women in alcohol concentrations. Discussion—These findings show that alcohol use is an important factor in A&E attendance, but it should not be assumed that there is a causal relation between alcohol use and injury. Several accident related and sociodemographic variables were predictive of alcohol use before attending. The overall level of prediction was too weak to permit accurate identification of drinkers for screening purposes, but routine alcohol concentration assessments may be

  20. Conditional Granger causality and partitioned Granger causality: differences and similarities.

    PubMed

    Malekpour, Sheida; Sethares, William A

    2015-12-01

    Neural information modeling and analysis often requires a measurement of the mutual influence among many signals. A common technique is the conditional Granger causality (cGC) which measures the influence of one time series on another time series in the presence of a third. Geweke has translated this condition into the frequency domain and has explored the mathematical relationships between the time and frequency domain expressions. Chen has observed that in practice, the expressions may return (meaningless) negative numbers, and has proposed an alternative which is based on a partitioned matrix scheme, which we call partitioned Granger causality (pGC). There has been some confusion in the literature about the relationship between cGC and pGC; some authors treat them as essentially identical measures, while others have noted that some properties (such as the relationship between the time and frequency domain expressions) do not hold for the pGC. This paper presents a series of matrix equalities that simplify the calculation of the pGC. In this simplified expression, the essential differences and similarities between the cGC and the pGC become clear; in essence, the pGC is dependent on only a subset of the parameters in the model estimation, and the noise residuals (which are uncorrelated in the cGC) need not be uncorrelated in the pGC. The mathematical results are illustrated with a simulation, and the measures are applied to an EEG dataset.

  1. Accident management information needs

    SciTech Connect

    Hanson, D.J.; Ward, L.W.; Nelson, W.R.; Meyer, O.R. )

    1990-04-01

    In support of the US Nuclear Regulatory Commission (NRC) Accident Management Research Program, a methodology has been developed for identifying the plant information needs necessary for personnel involved in the management of an accident to diagnose that an accident is in progress, select and implement strategies to prevent or mitigate the accident, and monitor the effectiveness of these strategies. This report describes the methodology and presents an application of this methodology to a Pressurized Water Reactor (PWR) with a large dry containment. A risk-important severe accident sequence for a PWR is used to examine the capability of the existing measurements to supply the necessary information. The method includes an assessment of the effects of the sequence on the measurement availability including the effects of environmental conditions. The information needs and capabilities identified using this approach are also intended to form the basis for more comprehensive information needs assessment performed during the analyses and development of specific strategies for use in accident management prevention and mitigation. 3 refs., 16 figs., 7 tabs.

  2. Scalar Fields via Causal Tapestries

    NASA Astrophysics Data System (ADS)

    Sulis, William

    2012-02-01

    Causal tapestries provide a framework for implementing an explicit Process Theory approach to quantum foundations which models information flow within a physical system. We consider event-transition tapestry pairs. An event tapestry O is a 4-tuple (L, K, M, Ip ) where K is an index set of cardinality κ, M = M x F(M) x D x P(M') a mathematical structure with M a causal space, F(M) a function space, D a descriptor space, P(M') either a Lie algebra or tangent space on a manifold M', Ip an event tapestry. L consists of elements of the form [n]<α>G, n in K, α in M and G an acyclic directed graph whose vertex set is a subset of Lp Likewise, a transition tapestry π is a 4-tuple (L', K', M', I'p ) where M' = M' x F(M') x D' x P'(M). The dynamic generates a consistent succession of O-π pairs by means of a game based on the technique of forcing used in logic to generate models. This dynamic has previously been shown to be compatible with Lorentz invariance. An application of this approach to model scalar fields is presented in which each informon is associated with a function of the form f(πk1 /σ1 ,,πkN /σN )sin ( σ1 t1 --πk1 )/ ( σ1 t1 --πk1 ) .sin ( σN tN --πkN )/ ( σN tN --πkN ) and the WSK interpolation theorem is used to generate the resulting scalar field on the causal manifold.

  3. Seasonal variability of iodine and selenium in surface and groundwater as a factor that may contribute to iodine isotope balance in the thyroid gland and its irradiation in case of radioiodine contamination during accidents at the NPP

    NASA Astrophysics Data System (ADS)

    Korobova, Elena; Kolmykova, Lyudmila; Ryzhenko, Boris; Berezkin, Viktor; Saraeva, Anastasia

    2016-04-01

    Radioiodine release to the environment during the accident at the Chernobyl NPP led to the increased risk of the thyroid cancer cases within the contaminated areas, the effect being aggravated in conditions of stable iodine and selenium deficiency in local food chains. Although the drinking water iodine is usually believed to contribute not more than 10% to local diet, our estimations accounting of water content in other products and several regional studies (e.g. India and Australia) proved its portion to be at least twice as much. As radioiodine isotopes are short-lived, their absorption depends greatly on stable iodine and selenium sufficiency in thyroid gland in the first few days of contamination and seasonal variation of stable iodine and selenium in local sources of drinking water may be significant as modifying the resulting thyroid irradiation in different seasons of the year. The main goal of the study was to evaluate seasonal variation of levels of iodine and selenium in natural waters of the Bryansk region as a possible factor affecting the radioiodine intake by thyroid gland of animals and humans in case of radioiodine contamination during the accident. Seasonal I and Se concentration was measured in the years of 2014 and 2015 at 14 test points characterizing surface (river and lake) and drinking groundwater. Obtained data proved considerable seasonal variation of I and Se concentration in natural waters (3,7-8,1 μg/l and 0,04-0,4 μg/l respectively) related to physico-chemical water parameters, such as pH, Eh and fluctuations in concentration of dissolved organic matter. The widest I and Se seasonal variability was observed in surface and well waters, maximum I level being found in autumn at the end of vegetation period characterized by active I leaching from the decomposed organic residues by long lasting precipitations. The content of selenium in the surface waters during summer-autumn (0,06-0,3 μg/l) was higher than in spring (0,04-0,05

  4. Space and time in perceptual causality.

    PubMed

    Straube, Benjamin; Chatterjee, Anjan

    2010-01-01

    Inferring causality is a fundamental feature of human cognition that allows us to theorize about and predict future states of the world. Michotte suggested that humans automatically perceive causality based on certain perceptual features of events. However, individual differences in judgments of perceptual causality cast doubt on Michotte's view. To gain insights in the neural basis of individual difference in the perception of causality, our participants judged causal relationships in animations of a blue ball colliding with a red ball (a launching event) while fMRI-data were acquired. Spatial continuity and temporal contiguity were varied parametrically in these stimuli. We did not find consistent brain activation differences between trials judged as caused and those judged as non-caused, making it unlikely that humans have universal instantiation of perceptual causality in the brain. However, participants were slower to respond to and showed greater neural activity for violations of causality, suggesting that humans are biased to expect causal relationships when moving objects appear to interact. Our participants demonstrated considerable individual differences in their sensitivity to spatial and temporal characteristics in perceiving causality. These qualitative differences in sensitivity to time or space in perceiving causality were instantiated in individual differences in activation of the left basal ganglia or right parietal lobe, respectively. Thus, the perception that the movement of one object causes the movement of another is triggered by elemental spatial and temporal sensitivities, which themselves are instantiated in specific distinct neural networks. PMID:20463866

  5. Environmental aftermath of the radiation accident at Tomsk-7

    SciTech Connect

    Porfiriev, B.N. |

    1996-01-01

    An analysis is presented of the environmental effects of the most serious radiation accident recorded after Chernobyl, which occurred in the formerly secret town of Tomsk-7 in Siberia, Russia, on 6, April 1993. Fortunately, it appears not to have become a major industrial crisis or disaster. The causes of the accident are described. It is argued that a mixture of both objective and subjective prerequisites, including specific human, organizational, and technological factors, were responsible for the explosion or directly facilitated it. The Tomsk-7 accident`s ecological, medical, social, and psychological consequences are discussed. 33 refs., 1 figs., 1 tab.

  6. Helicopter sling load accident/incident survey: 1968 - 1974

    NASA Technical Reports Server (NTRS)

    Shaughnessy, J. D.; Pardue, M. D.

    1977-01-01

    During the period considered a mean of eleven accidents per year occurred and a mean of eleven persons were killed or seriously injured per year. Forty-one percent of the accidents occurred during hover, and 63 percent of the accidents had pilot error listed as a cause/factor. Many accidents involved pilots losing control of the helicopter or allowing a collision with obstructions to occur. There was a mean of 58 incidents each year and 51 percent of these occurred during cruise.

  7. A novel approach for identifying causal models of complex diseases from family data.

    PubMed

    Park, Leeyoung; Kim, Ju H

    2015-04-01

    Causal models including genetic factors are important for understanding the presentation mechanisms of complex diseases. Familial aggregation and segregation analyses based on polygenic threshold models have been the primary approach to fitting genetic models to the family data of complex diseases. In the current study, an advanced approach to obtaining appropriate causal models for complex diseases based on the sufficient component cause (SCC) model involving combinations of traditional genetics principles was proposed. The probabilities for the entire population, i.e., normal-normal, normal-disease, and disease-disease, were considered for each model for the appropriate handling of common complex diseases. The causal model in the current study included the genetic effects from single genes involving epistasis, complementary gene interactions, gene-environment interactions, and environmental effects. Bayesian inference using a Markov chain Monte Carlo algorithm (MCMC) was used to assess of the proportions of each component for a given population lifetime incidence. This approach is flexible, allowing both common and rare variants within a gene and across multiple genes. An application to schizophrenia data confirmed the complexity of the causal factors. An analysis of diabetes data demonstrated that environmental factors and gene-environment interactions are the main causal factors for type II diabetes. The proposed method is effective and useful for identifying causal models, which can accelerate the development of efficient strategies for identifying causal factors of complex diseases. PMID:25701286

  8. Causal diagrams in systems epidemiology

    PubMed Central

    2012-01-01

    Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s). Transmitted causes ("causes of causes") tend not to be systematically analysed. The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties. The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets. Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback. PMID:22429606

  9. Quality function deployment applied to local traffic accident reduction.

    PubMed

    Sohn, S Y

    1999-11-01

    One of the major tasks of police stations is the management of local road traffic accidents. Proper prevention policy which reflects the local accident characteristics could immensely help individual police stations in decreasing various severity levels of road traffic accidents. In order to relate accident variation to local driving environmental characteristics, we use both cluster analysis and Poisson regression. The fitted result at the level of each cluster for each type of accident severity is utilized as an input to quality function deployment. Quality function deployment (QFD) has been applied to customer satisfaction in various industrial quality improvement settings, where several types of customer requirements are related to various control factors. We show how QFD enables one to set priorities on various road accident control policies to which each police station has to pay particular attention.

  10. Quality function deployment applied to local traffic accident reduction.

    PubMed

    Sohn, S Y

    1999-11-01

    One of the major tasks of police stations is the management of local road traffic accidents. Proper prevention policy which reflects the local accident characteristics could immensely help individual police stations in decreasing various severity levels of road traffic accidents. In order to relate accident variation to local driving environmental characteristics, we use both cluster analysis and Poisson regression. The fitted result at the level of each cluster for each type of accident severity is utilized as an input to quality function deployment. Quality function deployment (QFD) has been applied to customer satisfaction in various industrial quality improvement settings, where several types of customer requirements are related to various control factors. We show how QFD enables one to set priorities on various road accident control policies to which each police station has to pay particular attention. PMID:10487350

  11. Car accidents as a method of suicide: a comprehensive overview.

    PubMed

    Pompili, Maurizio; Serafini, Gianluca; Innamorati, Marco; Montebovi, Franco; Palermo, Mario; Campi, Sandra; Stefani, Henry; Giordano, Gloria; Telesforo, Ludovica; Amore, Mario; Girardi, Paolo

    2012-11-30

    The research literature provides evidence on the possible link between single-car accident drivers and suicidal intent, and some scholars have stressed the role of unconscious suicidal motivations in some single-car accidents. This paper review relevant literature on the topic and sheds light on neglected factors that may play a central role in reducing the number of deaths due to car accidents. We performed careful PubMed, and PsycInfo searches to identify all papers and book chapters in English during the period 1955-2011. Our overview of the literature indicates that above 2% of the traffic accidents are suicide behaviors. However, the phenomenon may be underreported, considering that suicides by car accidents may be reported as accidental in the national statistics. On the other hand, the association between accident-pronesses and unconscious self-destructive impulses is an issue that is difficult to solve.

  12. Drink driving and traffic accidents in young people.

    PubMed

    Horwood, L J; Fergusson, D M

    2000-11-01

    The relationship between drink driving behaviours and rates of traffic accidents was analysed in a birth cohort of 907 New Zealand young people studied to the age of 21. Drink driving was significantly (P < 0.0001) related to active traffic accidents in which the driver's behaviour contributed to the accident but was not related to passive accidents in which driver behaviours did not contribute to the accident (P > 0.15). Those engaging in high rates of drink driving had rates of active traffic accidents that were 2.6 times higher than those who did not drink and drive. Further analysis suggested that much of this association was explained by confounding factors (and notably driver behaviour) that were associated with both drink driving and accident rates. After adjustment for confounding factors, those engaging in high rates of drink driving had rates of active accidents that were 1.5 (P < 0.01) times higher than those who did not drink and drive. It is concluded that although the study findings support the view that the regulation of drink driving behaviour amongst young people is likely to contribute to a reduction in traffic accidents, to be fully effective attempts at regulation of drink driving also need to be accompanied by a similar level of investment in regulating other aspects of risky or illegal driving behaviour amongst young people. PMID:10994608

  13. 49 CFR 655.44 - Post-accident testing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Safety Administration rule 49 CFR 389.303(a)(1) or (b)(1). (ii) The employer shall also drug and alcohol... completely discounted as a contributing factor to the accident. The employer shall also drug and alcohol test... require the delay of necessary medical attention for the injured following an accident or to prohibit...

  14. 49 CFR 655.44 - Post-accident testing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Safety Administration rule 49 CFR 389.303(a)(1) or (b)(1). (ii) The employer shall also drug and alcohol... completely discounted as a contributing factor to the accident. The employer shall also drug and alcohol test... require the delay of necessary medical attention for the injured following an accident or to prohibit...

  15. 49 CFR 655.44 - Post-accident testing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Safety Administration rule 49 CFR 389.303(a)(1) or (b)(1). (ii) The employer shall also drug and alcohol... completely discounted as a contributing factor to the accident. The employer shall also drug and alcohol test... require the delay of necessary medical attention for the injured following an accident or to prohibit...

  16. Self-esteem and causal attributions.

    PubMed

    Chandler, T A; Lee, M S; Pengilly, J W

    1997-11-01

    The relationship between self-esteem and causal attributions of success and failure in achievement-related behavior was examined among undergraduate students. An integration of a self-consistency model of causal attribution and self-enhancement theory was attempted. Self-esteem and performance outcome conditions of success and failure served as independent variables. Success and failure conditions were created via feedback regarding the participants' performance on an anagram task. The participants' attributions of six causal elements (ability, effort, immediate effort, task difficulty, luck, and mood) were categorized and combined with three causal dimensions (internal-external locus, stability, and controllability), which served as dependent variables. Participants' expectations regarding performance also served as a dependent variable. The relationship between self-esteem, expectancies of success and failure, performance, and stable causality were reported. In terms of causal dimensions, internal, stable, and controllable dimensions were explained by self-enhancement.

  17. There aren't plenty more fish in the sea: a causal network approach.

    PubMed

    Nikolic, Milena; Lagnado, David A

    2015-11-01

    The current research investigated how lay representations of the causes of an environmental problem may underlie individuals' reasoning about the issue. Naïve participants completed an experiment that involved two main tasks. The causal diagram task required participants to depict the causal relations between a set of factors related to overfishing and to estimate the strength of these relations. The counterfactual task required participants to judge the effect of counterfactual suppositions based on the diagrammed factors. We explored two major questions: (1) what is the relation between individual causal models and counterfactual judgments? Consistent with previous findings (e.g., Green et al., 1998, Br. J. Soc. Psychology, 37, 415), these judgments were best explained by a combination of the strength of both direct and indirect causal paths. (2) To what extent do people use two-way causal thinking when reasoning about an environmental problem? In contrast to previous research (e.g., White, 2008, Appl. Cogn. Psychology, 22, 559), analyses based on individual causal networks revealed the presence of numerous feedback loops. The studies support the value of analysing individual causal models in contrast to consensual representations. Theoretical and practical implications are discussed in relation to causal reasoning as well as environmental psychology.

  18. There aren't plenty more fish in the sea: a causal network approach.

    PubMed

    Nikolic, Milena; Lagnado, David A

    2015-11-01

    The current research investigated how lay representations of the causes of an environmental problem may underlie individuals' reasoning about the issue. Naïve participants completed an experiment that involved two main tasks. The causal diagram task required participants to depict the causal relations between a set of factors related to overfishing and to estimate the strength of these relations. The counterfactual task required participants to judge the effect of counterfactual suppositions based on the diagrammed factors. We explored two major questions: (1) what is the relation between individual causal models and counterfactual judgments? Consistent with previous findings (e.g., Green et al., 1998, Br. J. Soc. Psychology, 37, 415), these judgments were best explained by a combination of the strength of both direct and indirect causal paths. (2) To what extent do people use two-way causal thinking when reasoning about an environmental problem? In contrast to previous research (e.g., White, 2008, Appl. Cogn. Psychology, 22, 559), analyses based on individual causal networks revealed the presence of numerous feedback loops. The studies support the value of analysing individual causal models in contrast to consensual representations. Theoretical and practical implications are discussed in relation to causal reasoning as well as environmental psychology. PMID:25597224

  19. Multiple Causality: Consequences for Medical Practice

    PubMed Central

    Nydegger, Corinne N.

    1983-01-01

    When a scientifically trained health professional is called upon to deal with patients holding differing causal views of illness, the resulting lack of communication is frustrating to both. This discussion traces some implications for medical practice of significant cultural differences in two aspects of causal paradigms of illness: (1) terms accepted and (2) dimension or level of causality typically sought. The second is the more pervasive and intractable problem, having distinctive consequences for the role of curer, symptomatology, diagnosis and treatment. PMID:6858133

  20. Nonparametric causal inference for bivariate time series.

    PubMed

    McCracken, James M; Weigel, Robert S

    2016-02-01

    We introduce new quantities for exploratory causal inference between bivariate time series. The quantities, called penchants and leanings, are computationally straightforward to apply, follow directly from assumptions of probabilistic causality, do not depend on any assumed models for the time series generating process, and do not rely on any embedding procedures; these features may provide a clearer interpretation of the results than those from existing time series causality tools. The penchant and leaning are computed based on a structured method for computing probabilities.

  1. Physical integration: a causal account for consciousness.

    PubMed

    Manzotti, Riccardo; Chella, Antonio

    2014-06-01

    The issue of integration in neural networks is intimately connected with that of consciousness. In this paper, integration as an effective level of physical organization is contrasted with a methodological integrative approach. Understanding how consciousness arises out of neural processes requires a model of integration in just causal physical terms. Based on a set of feasible criteria (physical grounding, causal efficacy, no circularity and scaling), a causal account of physical integration for consciousness centered on joint causation is outlined.

  2. Causal inference in economics and marketing

    PubMed Central

    Varian, Hal R.

    2016-01-01

    This is an elementary introduction to causal inference in economics written for readers familiar with machine learning methods. The critical step in any causal analysis is estimating the counterfactual—a prediction of what would have happened in the absence of the treatment. The powerful techniques used in machine learning may be useful for developing better estimates of the counterfactual, potentially improving causal inference. PMID:27382144

  3. Causal inference in economics and marketing.

    PubMed

    Varian, Hal R

    2016-07-01

    This is an elementary introduction to causal inference in economics written for readers familiar with machine learning methods. The critical step in any causal analysis is estimating the counterfactual-a prediction of what would have happened in the absence of the treatment. The powerful techniques used in machine learning may be useful for developing better estimates of the counterfactual, potentially improving causal inference. PMID:27382144

  4. Nonparametric causal inference for bivariate time series

    NASA Astrophysics Data System (ADS)

    McCracken, James M.; Weigel, Robert S.

    2016-02-01

    We introduce new quantities for exploratory causal inference between bivariate time series. The quantities, called penchants and leanings, are computationally straightforward to apply, follow directly from assumptions of probabilistic causality, do not depend on any assumed models for the time series generating process, and do not rely on any embedding procedures; these features may provide a clearer interpretation of the results than those from existing time series causality tools. The penchant and leaning are computed based on a structured method for computing probabilities.

  5. Alterations in White Matter Microstructure as Vulnerability Factors and Acquired Signs of Traffic Accident-Induced PTSD

    PubMed Central

    Ding, Weina; Wan, Jieqing; Zhuang, Zhiguo; Zhang, Yong; Liu, Yijun

    2013-01-01

    It remains unclear whether white matter (WM) changes found in post-traumatic stress disorder (PTSD) patients are stress-induced or precursors for vulnerability. The current study aimed to identify susceptibility factors relating to the development of PTSD and to examine the ability of these factors to predict the course of longitudinal PTSD. Sixty two victims who had experienced traffic accidents underwent diffusion tensor imaging using a 3.0T MRI system within 2 days after their accidents. Of these, 21 were diagnosed with PTSD at 1 or 6 months using the Clinician-Administered Ptsd Scale (CAPS). Then, 11 trauma-exposed victims with PTSD underwent the second MRI scan. Compared with the victims without PTSD, the victims with PTSD showed decreased fractional anisotropy (FA) in WM of the anterior cingulate cortex, ventromedial prefrontal cortex (vmPFC), temporal lobes and midbrain, and increased mean diffusivity (MD) in the vmPFC within 2 days after the traumatic event. Importantly, decreased FA of the vmPFC in the acute phase predicted greater future CAPS scores. In addition, we found decreased FA in the insula in the follow-up scan in the victims with PTSD, which correlated with the decreased FA of the vmPFC in their baseline scan. These results suggested that the WM might have changed within 2 days after the traumatic event in the individuals who would later develop PTSD. Furthermore, decreased FA of the vmPFC could be a possible vulnerability marker predicting future development of PTSD and may provide an outcome prediction of the acquired signs. PMID:24349515

  6. Injuries are not accidents

    PubMed Central

    Gutiérrez, María Isabel

    2014-01-01

    Injuries are the result of an acute exposure to exhort of energy or a consequence of a deficiency in a vital element that exceeds physiological thresholds resulting threatens life. They are classified as intentional or unintentional. Injuries are considered a global health issue because they cause more than 5 million deaths per year worldwide and they are an important contributor to the burden of disease, especially affecting people of low socioeconomic status in low- and middle-income countries. A common misconception exists where injuries are thought to be the same as accidents; however, accidents are largely used as chance events, without taken in consideration that all these are preventable. This review discusses injuries and accidents in the context of road traffic and emphasizes injuries as preventable events. An understanding of the essence of injuries enables the standardization of terminology in public use and facilitates the development of a culture of prevention among all of us. PMID:25386040

  7. Accident prevention manual

    SciTech Connect

    Not Available

    1998-05-01

    Among the many common needs and goals are the safety and well-being of families, ourselves, fellow employees, and the continuing success of this organization. To these ends--minimizing human suffering and economic waste--the Bonneville Power Administration (BPA) Accident Prevention Program and this Accident Prevention Manual (APM) are dedicated. The BPA Accident Prevention Program is revised as necessary to ensure compliance with relevant Federal safety and health standards. The mandatory rules herein express minimum requirements for dealing with the principal hazards inherent in daily work activities. These and other written requirements, which neither can nor should provide complete coverage of all work situations, must be continually reinforced through the sound and mature safety judgments of all workers on each assigned task. In the event of conflicting judgments, the more conservative interpretation shall prevail pending review and resolution by management.

  8. Causal compensated perturbations in cosmology

    NASA Technical Reports Server (NTRS)

    Veeraraghavan, Shoba; Stebbins, Albert

    1990-01-01

    A theoretical framework is developed to calculate linear perturbations in the gravitational and matter fields which arise causally in response to the presence of stiff matter sources in a FRW cosmology. It is shown that, in order to satisfy energy and momentum conservation, the gravitational fields of the source must be compensated by perturbations in the matter and gravitational fields, and the role of such compensation in containing the initial inhomogeneities in their subsequent evolution is discussed. A complete formal solution is derived in terms of Green functions for the perturbations produced by an arbitrary source in a flat universe containing cold dark matter. Approximate Green function solutions are derived for the late-time density perturbations and late-time gravitational waves in a universe containing a radiation fluid. A cosmological energy-momentum pseudotensor is defined to clarify the nature of energy and momentum conservation in the expanding universe.

  9. Childhood accidents. Three epidemiological studies on the etiology.

    PubMed

    Gustafsson, L H

    1977-01-01

    Three studies on childhood accidents are presented. The aim was to study the importance of different factors regarding the accidents in question. The following factors have then been taken into consideration: the enviromental hazard, the accident proneness, the supervision and the education. Methodologically the investigations were carried out with an epidemiological technique. One is of a descriptive nature and the other two more analytically oriented. The studies are based on two different 1-year-materials consisting of accidents among children recorded in the emergency departments of Ostersund Hospital and the University Hospital in Uppsala. The results indicate that risk factors in the children's physical milieu played an important role in the occurrence of the accidents: clearly identifiable risk factors in the environment could be connected with 52% of the accidents, whereas some deficiency in supervision was noted in 20%. The investigators could identify a number of specific risk factors. Attempts were made to examine how frequency and type of childhood accidents vary with the population structure and social structure in well-defined housing areas, but the results were hard to evaluate because of methodological problems. The results are presented against the background of a detailed discussion on central methodological problems in epidemiological accident research. It is pointed out in particular that epidemiological methods have clear limitations in attempts at studying the low-frequency events that each individual type of accident in fact comprises. It is of great importance that in future research, side by side with the traditional epidemiological methods, other techniques are tested with the aim of obtaining maximal usable information from a detailed study of individual accidents and their backgrounds. PMID:857307

  10. Error-Based Accidents and Security Incidents in Nuclear Materials Management

    SciTech Connect

    Pond, Daniel J.; Greitzer, Frank L.

    2005-07-29

    Hazard and risk assessments, along with human error analysis and mitigation techniques, have long been mainstays of effective safety programs. These tools have revealed that worker errors contributing to or resulting in accidents are often the consequence of ineffective system conditions, process features, or individual employee characteristics. At Los Alamos National Laboratory (LANL), security, safety, human error, and organizational analysts determined that the system-induced human errors that make accidents more likely also are contributing to security incidents. A similar set of system conditions has been found to underlie deliberate, non-malevolent deviations from proper security practices—termed breaches—that also can result in a security incident. In fiscal-year (FY) 2002, LANL's Security Division therefore established the ESTHER (Enhanced Security Through Human Error Reduction) program to identify and reduce the influence of the factors that underlie employee errors and breaches and, in turn, security incidents. Recognizing the potential benefits of this program and approach, in FY2004 the Department of Energy (DOE) Office of Security Policy (DOE-SO) funded an expansion of ESTHER implementation to the causal assessment and reporting of security incidents at other DOE sites. This presentation will focus on three applications of error/breach assessment and mitigation techniques. One use is proactive, accomplished through the elimination of contributors to error, whereas two are reactive, implemented in response to accidents or security incidents as well as to near misses, to prevent recurrence. The human performance and safety bases of these techniques will be detailed. Associated tools—including computer-based assessment training and web-based incident reporting modules developed by Pacific Northwest National Laboratory—will be discussed.

  11. Perception of risk and the attribution of responsibility for accidents.

    PubMed

    Rickard, Laura N

    2014-03-01

    Accidents, one often hears, "happen"; we accept, and even expect, that they will be part of daily life. But in situations in which injury or death result, judgments of responsibility become critical. How might our perceptions of risk influence the ways in which we allocate responsibility for an accident? Drawing from attribution and risk perception theory, this study investigates how perceived controllability and desirability of risk, in addition to perceived danger and recreational risk-taking, relate to attributions of responsibility for the cause of unintentional injury in a unique setting: U.S. national parks. Three parks, Mount Rainier, Olympic, and Delaware Water Gap, provide the setting for this survey-based study, which considers how park visitors (N = 447) attribute responsibility for the cause of a hypothetical visitor accident. Results suggest that respondents tended to make more internal (i.e., related to characteristics of the victim), rather than external (i.e., related to characteristics of the park, or park management) attributions. As respondents viewed park-related risk as controllable, they were more likely to attribute the cause of the accident to the victim. Moreover, among other significant variables, having experienced a similar accident predicted lower internal causal attribution. Opportunities for future research linking risk perception and attribution variables, as well as practical implications for the management of public outdoor settings, are presented.

  12. Simulation Modeling Requirements for Loss-of-Control Accident Prevention of Turboprop Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Crider, Dennis; Foster, John V.

    2012-01-01

    In-flight loss of control remains the leading contributor to aviation accident fatalities, with stall upsets being the leading causal factor. The February 12, 2009. Colgan Air, Inc., Continental Express flight 3407 accident outside Buffalo, New York, brought this issue to the forefront of public consciousness and resulted in recommendations from the National Transportation Safety Board to conduct training that incorporates stalls that are fully developed and develop simulator standards to support such training. In 2010, Congress responded to this accident with Public Law 11-216 (Section 208), which mandates full stall training for Part 121 flight operations. Efforts are currently in progress to develop recommendations on implementation of stall training for airline pilots. The International Committee on Aviation Training in Extended Envelopes (ICATEE) is currently defining simulator fidelity standards that will be necessary for effective stall training. These recommendations will apply to all civil transport aircraft including straight-wing turboprop aircraft. Government-funded research over the previous decade provides a strong foundation for stall/post-stall simulation for swept-wing, conventional tail jets to respond to this mandate, but turboprops present additional and unique modeling challenges. First among these challenges is the effect of power, which can provide enhanced flow attachment behind the propellers. Furthermore, turboprops tend to operate for longer periods in an environment more susceptible to ice. As a result, there have been a significant number of turboprop accidents as a result of the early (lower angle of attack) stalls in icing. The vulnerability of turboprop configurations to icing has led to studies on ice accumulation and the resulting effects on flight behavior. Piloted simulations of these effects have highlighted the important training needs for recognition and mitigation of icing effects, including the reduction of stall margins

  13. Causal Systems Categories: Differences in Novice and Expert Categorization of Causal Phenomena

    ERIC Educational Resources Information Center

    Rottman, Benjamin M.; Gentner, Dedre; Goldwater, Micah B.

    2012-01-01

    We investigated the understanding of causal systems categories--categories defined by common causal structure rather than by common domain content--among college students. We asked students who were either novices or experts in the physical sciences to sort descriptions of real-world phenomena that varied in their causal structure (e.g., negative…

  14. The Power of Causal Beliefs and Conflicting Evidence on Causal Judgments and Decision Making

    ERIC Educational Resources Information Center

    Garcia-Retamero, Rocio; Muller, Stephanie M.; Catena, Andres; Maldonado, Antonio

    2009-01-01

    In two experiments, we investigated the relative impact of causal beliefs and empirical evidence on both decision making and causal judgments, and whether this relative impact could be altered by previous experience. 2. Selected groups of participants in both experiments received pre-training with either causal or neutral cues, or no pre-training…

  15. Causality and persistence in ecological systems: a nonparametric spectral granger causality approach.

    PubMed

    Detto, Matteo; Molini, Annalisa; Katul, Gabriel; Stoy, Paul; Palmroth, Sari; Baldocchi, Dennis

    2012-04-01

    Abstract Directionality in coupling, defined as the linkage relating causes to their effects at a later time, can be used to explain the core dynamics of ecological systems by untangling direct and feedback relationships between the different components of the systems. Inferring causality from measured ecological variables sampled through time remains a formidable challenge further made difficult by the action of periodic drivers overlapping the natural dynamics of the system. Periodicity in the drivers can often mask the self-sustained oscillations originating from the autonomous dynamics. While linear and direct causal relationships are commonly addressed in the time domain, using the well-established machinery of Granger causality (G-causality), the presence of periodic forcing requires frequency-based statistics (e.g., the Fourier transform), able to distinguish coupling induced by oscillations in external drivers from genuine endogenous interactions. Recent nonparametric spectral extensions of G-causality to the frequency domain pave the way for the scale-by-scale decomposition of causality, which can improve our ability to link oscillatory behaviors of ecological networks to causal mechanisms. The performance of both spectral G-causality and its conditional extension for multivariate systems is explored in quantifying causal interactions within ecological networks. Through two case studies involving synthetic and actual time series, it is demonstrated that conditional G-causality outperforms standard G-causality in identifying causal links and their concomitant timescales.

  16. Development of Database for Accident Analysis in Indian Mines

    NASA Astrophysics Data System (ADS)

    Tripathy, Debi Prasad; Guru Raghavendra Reddy, K.

    2015-08-01

    Mining is a hazardous industry and high accident rates associated with underground mining is a cause of deep concern. Technological developments notwithstanding, rate of fatal accidents and reportable incidents have not shown corresponding levels of decline. This paper argues that adoption of appropriate safety standards by both mine management and the government may result in appreciable reduction in accident frequency. This can be achieved by using the technology in improving the working conditions, sensitising workers and managers about causes and prevention of accidents. Inputs required for a detailed analysis of an accident include information on location, time, type, cost of accident, victim, nature of injury, personal and environmental factors etc. Such information can be generated from data available in the standard coded accident report form. This paper presents a web based application for accident analysis in Indian mines during 2001-2013. An accident database (SafeStat) prototype based on Intranet of the TCP/IP agreement, as developed by the authors, is also discussed.

  17. [Psychosocial aspects and accidents in land transport].

    PubMed

    Morales-Soto, Nelson; Alfaro-Basso, Daniel; Gálvez-Rivero, Wilfredo

    2010-06-01

    Road traffic accidents are a public health problem in Peru, having caused 35 596 deaths in Peru between 1998 and 2008. Lima is the most affected region, presenting 61.7% of the accidents, the annual cost reached one thousand million dollars, equivalent to a third part of the investment in health. Available studies give emphasis to the protagonists--the drivers, the pedestrians--or to equipment and roads; the laws have been modified and containment plans for accidents have been implemented, but the incidence remains the same. We raise the possibility of exploring behavioral and social factors that could be relevant in the genesis of the problem, revising those related to current disorder in transport, the behaviors of drivers and pedestrians and the permissiveness of society in general particularly of the authority. We propose research and a multidisciplinary and intersectoral intervention. PMID:21072481

  18. Single pilot IFR accident data analysis

    NASA Technical Reports Server (NTRS)

    Harris, D. F.; Morrisete, J. A.

    1982-01-01

    The aircraft accident data recorded and maintained by the National Transportation Safety Board for 1964 to 1979 were analyzed to determine what problems exist in the general aviation single pilot instrument flight rules environment. A previous study conducted in 1978 for the years 1964 to 1975 provided a basis for comparison. The purpose was to determine what changes, if any, have occurred in trends and cause-effect relationships reported in the earlier study. The increasing numbers have been tied to measures of activity to produce accident rates which in turn were analyzed in terms of change. Where anomalies or unusually high accident rates were encountered, further analysis was conducted to isolate pertinent patterns of cause factors and/or experience levels of involved pilots. The bulk of the effort addresses accidents in the landing phase of operations. A detailed analysis was performed on controlled/uncontrolled collisions and their unique attributes delineated. Estimates of day vs. night general aviation activity and accident rates were obtained.

  19. Inference and Action in Early Causal Reasoning.

    ERIC Educational Resources Information Center

    Frye, Douglas; And Others

    1996-01-01

    Two marble-and-ramp experiments investigated whether a simple-to-embedded-rules account can explain changes in children's causal reasoning. Results indicated that the same difference between three- and four-year olds in the prediction experiment appeared in the action experiment, suggesting that the same rules may underlie causal action as well as…

  20. Spin foam models as energetic causal sets

    NASA Astrophysics Data System (ADS)

    Cortês, Marina; Smolin, Lee

    2016-04-01

    Energetic causal sets are causal sets endowed by a flow of energy-momentum between causally related events. These incorporate a novel mechanism for the emergence of space-time from causal relations [M. Cortês and L. Smolin, Phys. Rev. D 90, 084007 (2014); Phys. Rev. D 90, 044035 (2014)]. Here we construct a spin foam model which is also an energetic causal set model. This model is closely related to the model introduced in parallel by Wolfgang Wieland in [Classical Quantum Gravity 32, 015016 (2015)]. What makes a spin foam model also an energetic causal set is Wieland's identification of new degrees of freedom analogous to momenta, conserved at events (or four-simplices), whose norms are not mass, but the volume of tetrahedra. This realizes the torsion constraints, which are missing in previous spin foam models, and are needed to relate the connection dynamics to those of the metric, as in general relativity. This identification makes it possible to apply the new mechanism for the emergence of space-time to a spin foam model. Our formulation also makes use of Markopoulou's causal formulation of spin foams [arXiv:gr-qc/9704013]. These are generated by evolving spin networks with dual Pachner moves. This endows the spin foam history with causal structure given by a partial ordering of the events which are dual to four-simplices.

  1. Updating during Reading Comprehension: Why Causality Matters

    ERIC Educational Resources Information Center

    Kendeou, Panayiota; Smith, Emily R.; O'Brien, Edward J.

    2013-01-01

    The present set of 7 experiments systematically examined the effectiveness of adding causal explanations to simple refutations in reducing or eliminating the impact of outdated information on subsequent comprehension. The addition of a single causal-explanation sentence to a refutation was sufficient to eliminate any measurable disruption in…

  2. Causal Inferences in the Campbellian Validity System

    ERIC Educational Resources Information Center

    Lund, Thorleif

    2010-01-01

    The purpose of the present paper is to critically examine causal inferences and internal validity as defined by Campbell and co-workers. Several arguments are given against their counterfactual effect definition, and this effect definition should be considered inadequate for causal research in general. Moreover, their defined independence between…

  3. Campbell's and Rubin's Perspectives on Causal Inference

    ERIC Educational Resources Information Center

    West, Stephen G.; Thoemmes, Felix

    2010-01-01

    Donald Campbell's approach to causal inference (D. T. Campbell, 1957; W. R. Shadish, T. D. Cook, & D. T. Campbell, 2002) is widely used in psychology and education, whereas Donald Rubin's causal model (P. W. Holland, 1986; D. B. Rubin, 1974, 2005) is widely used in economics, statistics, medicine, and public health. Campbell's approach focuses on…

  4. Granger causality for state-space models

    NASA Astrophysics Data System (ADS)

    Barnett, Lionel; Seth, Anil K.

    2015-04-01

    Granger causality has long been a prominent method for inferring causal interactions between stochastic variables for a broad range of complex physical systems. However, it has been recognized that a moving average (MA) component in the data presents a serious confound to Granger causal analysis, as routinely performed via autoregressive (AR) modeling. We solve this problem by demonstrating that Granger causality may be calculated simply and efficiently from the parameters of a state-space (SS) model. Since SS models are equivalent to autoregressive moving average models, Granger causality estimated in this fashion is not degraded by the presence of a MA component. This is of particular significance when the data has been filtered, downsampled, observed with noise, or is a subprocess of a higher dimensional process, since all of these operations—commonplace in application domains as diverse as climate science, econometrics, and the neurosciences—induce a MA component. We show how Granger causality, conditional and unconditional, in both time and frequency domains, may be calculated directly from SS model parameters via solution of a discrete algebraic Riccati equation. Numerical simulations demonstrate that Granger causality estimators thus derived have greater statistical power and smaller bias than AR estimators. We also discuss how the SS approach facilitates relaxation of the assumptions of linearity, stationarity, and homoscedasticity underlying current AR methods, thus opening up potentially significant new areas of research in Granger causal analysis.

  5. Quasi-Experimental Designs for Causal Inference

    ERIC Educational Resources Information Center

    Kim, Yongnam; Steiner, Peter

    2016-01-01

    When randomized experiments are infeasible, quasi-experimental designs can be exploited to evaluate causal treatment effects. The strongest quasi-experimental designs for causal inference are regression discontinuity designs, instrumental variable designs, matching and propensity score designs, and comparative interrupted time series designs. This…

  6. Causal Indicator Models: Identification, Estimation, and Testing

    ERIC Educational Resources Information Center

    Bollen, Kenneth A.; Davis, Walter R.

    2009-01-01

    We discuss the identification, estimation, and testing of structural equation models that have causal indicators. We first provide 2 rules of identification that are particularly helpful in models with causal indicators--the 2C emitted paths rule and the exogenous X rule. We demonstrate how these rules can help us distinguish identified from…

  7. Compact Representations of Extended Causal Models

    ERIC Educational Resources Information Center

    Halpern, Joseph Y.; Hitchcock, Christopher

    2013-01-01

    Judea Pearl (2000) was the first to propose a definition of actual causation using causal models. A number of authors have suggested that an adequate account of actual causation must appeal not only to causal structure but also to considerations of "normality." In Halpern and Hitchcock (2011), we offer a definition of actual causation…

  8. A Causal Model of Faculty Research Productivity.

    ERIC Educational Resources Information Center

    Bean, John P.

    A causal model of faculty research productivity was developed through a survey of the literature. Models of organizational behavior, organizational effectiveness, and motivation were synthesized into a causal model of productivity. Two general types of variables were assumed to affect individual research productivity: institutional variables and…

  9. Causal Moderation Analysis Using Propensity Score Methods

    ERIC Educational Resources Information Center

    Dong, Nianbo

    2012-01-01

    This paper is based on previous studies in applying propensity score methods to study multiple treatment variables to examine the causal moderator effect. The propensity score methods will be demonstrated in a case study to examine the causal moderator effect, where the moderators are categorical and continuous variables. Moderation analysis is an…

  10. A copula approach to assessing Granger causality.

    PubMed

    Hu, Meng; Liang, Hualou

    2014-10-15

    In neuroscience, as in many other fields of science and engineering, it is crucial to assess the causal interactions among multivariate time series. Granger causality has been increasingly used to identify causal influence between time series based on multivariate autoregressive models. Such an approach is based on linear regression framework with implicit Gaussian assumption of model noise residuals having constant variance. As a consequence, this measure cannot detect the cause-effect relationship in high-order moments and nonlinear causality. Here, we propose an effective model-free, copula-based Granger causality measure that can be used to reveal nonlinear and high-order moment causality. We first formulate Granger causality as the log-likelihood ratio in terms of conditional distribution, and then derive an efficient estimation procedure using conditional copula. We use resampling techniques to build a baseline null-hypothesis distribution from which statistical significance can be derived. We perform a series of simulations to investigate the performance of our copula-based Granger causality, and compare its performance against other state-of-the-art techniques. Our method is finally applied to neural field potential time series recorded from visual cortex of a monkey while performing a visual illusion task.

  11. Controlling for causally relevant third variables.

    PubMed

    Goodie, Adam S; Williams, Cristina C; Crooks, C L

    2003-10-01

    In 3 experiments, the authors tested the conditions under which 3rd variables are controlled for in making causal judgments. The authors hypothesized that 3rd variables are controlled for when the 3rd variables are themselves perceived as causal. In Experiment 1, the participants predicted test performance after seeing information about wearing a lucky garment, taking a test-preparation course, and staying up late. The course (perceived as more causally relevant) was controlled for more than was the garment (perceived as less causally relevant) in assessing the effectiveness of staying up late. In Experiments 2 and 3, to obviate the many alternative accounts that arise from the realistic cover story of Experiment 1, participants predicted flowers' blooming after the presentation or nonpresentation of liquids. When one liquid was trained as causal, it was controlled for more in judging another liquid than when it was trained as neutral. Overall, stimuli perceived as causal were controlled for more when judging other stimuli. The authors concluded that the effect of perceived causal relevance on causal conditionalizing is real and normatively reasonable. PMID:14672103

  12. On the spectral formulation of Granger causality.

    PubMed

    Chicharro, D

    2011-12-01

    Spectral measures of causality are used to explore the role of different rhythms in the causal connectivity between brain regions. We study several spectral measures related to Granger causality, comprising the bivariate and conditional Geweke measures, the directed transfer function, and the partial directed coherence. We derive the formulation of dependence and causality in the spectral domain from the more general formulation in the information-theory framework. We argue that the transfer entropy, the most general measure derived from the concept of Granger causality, lacks a spectral representation in terms of only the processes associated with the recorded signals. For all the spectral measures we show how they are related to mutual information rates when explicitly considering the parametric autoregressive representation of the processes. In this way we express the conditional Geweke spectral measure in terms of a multiple coherence involving innovation variables inherent to the autoregressive representation. We also link partial directed coherence with Sims' criterion of causality. Given our results, we discuss the causal interpretation of the spectral measures related to Granger causality and stress the necessity to explicitly consider their specific formulation based on modeling the signals as linear Gaussian stationary autoregressive processes.

  13. Causal Mediation Analysis: Warning! Assumptions Ahead

    ERIC Educational Resources Information Center

    Keele, Luke

    2015-01-01

    In policy evaluations, interest may focus on why a particular treatment works. One tool for understanding why treatments work is causal mediation analysis. In this essay, I focus on the assumptions needed to estimate mediation effects. I show that there is no "gold standard" method for the identification of causal mediation effects. In…

  14. Essays on Causal Inference for Public Policy

    ERIC Educational Resources Information Center

    Zajonc, Tristan

    2012-01-01

    Effective policymaking requires understanding the causal effects of competing proposals. Relevant causal quantities include proposals' expected effect on different groups of recipients, the impact of policies over time, the potential trade-offs between competing objectives, and, ultimately, the optimal policy. This dissertation studies causal…

  15. Road Traffic Accident Analysis of Ajmer City Using Remote Sensing and GIS Technology

    NASA Astrophysics Data System (ADS)

    Bhalla, P.; Tripathi, S.; Palria, S.

    2014-12-01

    With advancement in technology, new and sophisticated models of vehicle are available and their numbers are increasing day by day. A traffic accident has multi-facet characteristics associated with it. In India 93% of crashes occur due to Human induced factor (wholly or partly). For proper traffic accident analysis use of GIS technology has become an inevitable tool. The traditional accident database is a summary spreadsheet format using codes and mileposts to denote location, type and severity of accidents. Geo-referenced accident database is location-referenced. It incorporates a GIS graphical interface with the accident information to allow for query searches on various accident attributes. Ajmer city, headquarter of Ajmer district, Rajasthan has been selected as the study area. According to Police records, 1531 accidents occur during 2009-2013. Maximum accident occurs in 2009 and the maximum death in 2013. Cars, jeeps, auto, pickup and tempo are mostly responsible for accidents and that the occurrence of accidents is mostly concentrated between 4PM to 10PM. GIS has proved to be a good tool for analyzing multifaceted nature of accidents. While road safety is a critical issue, yet it is handled in an adhoc manner. This Study is a demonstration of application of GIS for developing an efficient database on road accidents taking Ajmer City as a study. If such type of database is developed for other cities, a proper analysis of accidents can be undertaken and suitable management strategies for traffic regulation can be successfully proposed.

  16. Causality methods in cosmetovigilance: comparison of Colipa and PLM versus global introspection.

    PubMed

    Zweers, P G M A; Gilmour, N J; Hepburn, P A; Gerritsen, R F; van Puijenbroek, E P

    2012-08-01

    The European Cosmetics Regulation requires a post-marketing system for detection of undesirable effects on human health of cosmetic products. Colipa, the European Cosmetic, toiletry and perfumery association, provided guidelines for causality assessment of these effects. In addition another causality method originally designed for causality rating in Post Launch Monitoring (PLM) of novel foods has been employed to assess causality of cosmetic products. In this study these two causality schemes for consumer cosmetic products were validated against clinical assessment, using the method of global introspection (GI) in 100 reported cases. Causality assessments were performed by three experienced assessors in pharmacovigilance. In the event of discordance between the assessors, an adapted Delphi method was used. The overall Spearman correlation coefficient was 0.74 for comparison of Colipa versus GI, whereas this was 0.50 for PLM versus GI. According to current guidelines, the sensitivity was 0.95 for both the Colipa and PLM method, specificity was 0.84 for Colipa and 0.40 for PLM. From these results it can be concluded the performance of the Colipa causality method yielded better correlation to GI than PLM causality method. The factor identified from comparison of these two schemes as having greatest impact was the course of the reaction.

  17. A comparison of the hazard perception ability of accident-involved and accident-free motorcycle riders.

    PubMed

    Cheng, Andy S K; Ng, Terry C K; Lee, Hoe C

    2011-07-01

    conceptualizing the influence of different driving behaviors so as to enrich our understanding of the role of human factors in road accidents and consequently develop effective countermeasures to prevent traffic accidents involving motorcycles.

  18. Canonical Granger causality between regions of interest.

    PubMed

    Ashrafulla, Syed; Haldar, Justin P; Joshi, Anand A; Leahy, Richard M

    2013-12-01

    Estimating and modeling functional connectivity in the brain is a challenging problem with potential applications in the understanding of brain organization and various neurological and neuropsychological conditions. An important objective in connectivity analysis is to determine the connections between regions of interest in the brain. However, traditional functional connectivity analyses have frequently focused on modeling interactions between time series recordings at individual sensors, voxels, or vertices despite the fact that a single region of interest will often include multiple such recordings. In this paper, we present a novel measure of interaction between regions of interest rather than individual signals. The proposed measure, termed canonical Granger causality, combines ideas from canonical correlation and Granger causality analysis to yield a measure that reflects directed causality between two regions of interest. In particular, canonical Granger causality uses optimized linear combinations of signals from each region of interest to enable accurate causality measurements from substantially less data compared to alternative multivariate methods that have previously been proposed for this scenario. The optimized linear combinations are obtained using a variation of a technique developed for optimization on the Stiefel manifold. We demonstrate the advantages of canonical Granger causality in comparison to alternative causality measures for a range of different simulated datasets. We also apply the proposed measure to local field potential data recorded in a macaque brain during a visuomotor task. Results demonstrate that canonical Granger causality can be used to identify causal relationships between striate and prestriate cortexes in cases where standard Granger causality is unable to identify statistically significant interactions.

  19. Causal systems categories: differences in novice and expert categorization of causal phenomena.

    PubMed

    Rottman, Benjamin M; Gentner, Dedre; Goldwater, Micah B

    2012-07-01

    We investigated the understanding of causal systems categories--categories defined by common causal structure rather than by common domain content--among college students. We asked students who were either novices or experts in the physical sciences to sort descriptions of real-world phenomena that varied in their causal structure (e.g., negative feedback vs. causal chain) and in their content domain (e.g., economics vs. biology). Our hypothesis was that there would be a shift from domain-based sorting to causal sorting with increasing expertise in the relevant domains. This prediction was borne out: the novice groups sorted primarily by domain and the expert group sorted by causal category. These results suggest that science training facilitates insight about causal structures.

  20. Analysis of Occupational Accident Fatalities and Injuries Among Male Group in Iran Between 2008 and 2012

    PubMed Central

    Alizadeh, Seyed Shamseddin; Mortazavi, Seyed Bagher; Sepehri, Mohammad Mehdi

    2015-01-01

    Background: Because of occupational accidents, permanent disabilities and deaths occur and economic and workday losses emerge. Objectives: The purpose of the present study was to investigate the factors responsible for occupational accidents occurred in Iran. Patients and Methods: The current study analyzed 1464 occupational accidents recorded by the Ministry of Labor and Social Affairs’ offices in Iran during 2008 - 2012. At first, general understanding of accidents was obtained using descriptive statistics. Afterwards, the chi-square test and Cramer’s V statistic (Vc) were used to determine the association between factors influencing the type of injury as occupational accident outcomes. Results: There was no significant association between marital status and time of day with the type of injury. However, activity sector, cause of accident, victim’s education, age of victim and victim’s experience were significantly associated with the type of injury. Conclusions: Successful accident prevention relies largely on knowledge about the causes of accidents. In any accident control activity, particularly in occupational accidents, correctly identifying high-risk groups and factors influencing accidents is the key to successful interventions. Results of this study can cause to increase accident awareness and enable workplace’s management to select and prioritize problem areas and safety system weakness in workplaces. PMID:26568848

  1. Spread of entanglement and causality

    NASA Astrophysics Data System (ADS)

    Casini, Horacio; Liu, Hong; Mezei, Márk

    2016-07-01

    We investigate causality constraints on the time evolution of entanglement entropy after a global quench in relativistic theories. We first provide a general proof that the so-called tsunami velocity is bounded by the speed of light. We then generalize the free particle streaming model of [1] to general dimensions and to an arbitrary entanglement pattern of the initial state. In more than two spacetime dimensions the spread of entanglement in these models is highly sensitive to the initial entanglement pattern, but we are able to prove an upper bound on the normalized rate of growth of entanglement entropy, and hence the tsunami velocity. The bound is smaller than what one gets for quenches in holographic theories, which highlights the importance of interactions in the spread of entanglement in many-body systems. We propose an interacting model which we believe provides an upper bound on the spread of entanglement for interacting relativistic theories. In two spacetime dimensions with multiple intervals, this model and its variations are able to reproduce intricate results exhibited by holographic theories for a significant part of the parameter space. For higher dimensions, the model bounds the tsunami velocity at the speed of light. Finally, we construct a geometric model for entanglement propagation based on a tensor network construction for global quenches.

  2. When Work is Related to Disease, What Establishes Evidence for a Causal Relation?

    PubMed Central

    2012-01-01

    Establishing a causal relationship between factors at work and disease is difficult for occupational physicians and researchers. This paper seeks to provide arguments for the judgement of evidence of causality in observational studies that relate work factors to disease. I derived criteria for the judgement of evidence of causality from the following sources: the criteria list of Hill, the approach by Rothman, the methods used by International Agency for Research on Cancer (IARC), and methods used by epidemiologists. The criteria are applied to two cases of putative occupational diseases; breast cancer caused by shift work and aerotoxic syndrome. Only three of the Hill criteria can be applied to an actual study. Rothman stresses the importance of confounding and alternative explanations than the putative cause. IARC closely follows Hill, but they also incorporate other than epidemiological evidence. Applied to shift work and breast cancer, these results have found moderate evidence for a causal relationship, but applied to the aerotoxic syndrome, there is an absence of evidence of causality. There are no ready to use algorithms for judgement of evidence of causality. Criteria from different sources lead to similar results and can make a conclusion of causality more or less likely. PMID:22993715

  3. Attitudes toward Others Depend upon Self and Other Causal Uncertainty

    PubMed Central

    Tobin, Stephanie J.; Osika, Matylda M.; McLanders, Mia

    2014-01-01

    People who are high in causal uncertainty doubt their own ability to understand the causes of social events. In three studies, we examined the effects of target and perceiver causal uncertainty on attitudes toward the target. Target causal uncertainty was manipulated via responses on a causal uncertainty scale in Studies 1 and 2, and with a scenario in Study 3. In Studies 1 and 2, we found that participants liked the low causal uncertainty target more than the high causal uncertainty target. This preference was stronger for low relative to high causal uncertainty participants because high causal uncertainty participants held more uncertain ideals. In Study 3, we examined the value individuals place upon causal understanding (causal importance) as an additional moderator. We found that regardless of their own causal uncertainty level, participants who were high in causal importance liked the low causal uncertainty target more than the high causal uncertainty target. However, when participants were low in causal importance, low causal uncertainty perceivers showed no preference and high causal uncertainty perceivers preferred the high causal uncertainty target. These findings reveal that goal importance and ideals can influence how perceivers respond to causal uncertainty in others. PMID:24504048

  4. Attitudes toward others depend upon self and other causal uncertainty.

    PubMed

    Tobin, Stephanie J; Osika, Matylda M; McLanders, Mia

    2014-01-01

    People who are high in causal uncertainty doubt their own ability to understand the causes of social events. In three studies, we examined the effects of target and perceiver causal uncertainty on attitudes toward the target. Target causal uncertainty was manipulated via responses on a causal uncertainty scale in Studies 1 and 2, and with a scenario in Study 3. In Studies 1 and 2, we found that participants liked the low causal uncertainty target more than the high causal uncertainty target. This preference was stronger for low relative to high causal uncertainty participants because high causal uncertainty participants held more uncertain ideals. In Study 3, we examined the value individuals place upon causal understanding (causal importance) as an additional moderator. We found that regardless of their own causal uncertainty level, participants who were high in causal importance liked the low causal uncertainty target more than the high causal uncertainty target. However, when participants were low in causal importance, low causal uncertainty perceivers showed no preference and high causal uncertainty perceivers preferred the high causal uncertainty target. These findings reveal that goal importance and ideals can influence how perceivers respond to causal uncertainty in others.

  5. Applying STAMP in Accident Analysis

    NASA Technical Reports Server (NTRS)

    Leveson, Nancy; Daouk, Mirna; Dulac, Nicolas; Marais, Karen

    2003-01-01

    Accident models play a critical role in accident investigation and analysis. Most traditional models are based on an underlying chain of events. These models, however, have serious limitations when used for complex, socio-technical systems. Previously, Leveson proposed a new accident model (STAMP) based on system theory. In STAMP, the basic concept is not an event but a constraint. This paper shows how STAMP can be applied to accident analysis using three different views or models of the accident process and proposes a notation for describing this process.

  6. Causal localizations in relativistic quantum mechanics

    SciTech Connect

    Castrigiano, Domenico P. L. Leiseifer, Andreas D.

    2015-07-15

    Causal localizations describe the position of quantum systems moving not faster than light. They are constructed for the systems with finite spinor dimension. At the center of interest are the massive relativistic systems. For every positive mass, there is the sequence of Dirac tensor-localizations, which provides a complete set of inequivalent irreducible causal localizations. They obey the principle of special relativity and are fully Poincaré covariant. The boosters are determined by the causal position operator and the other Poincaré generators. The localization with minimal spinor dimension is the Dirac localization. Thus, the Dirac equation is derived here as a mere consequence of the principle of causality. Moreover, the higher tensor-localizations, not known so far, follow from Dirac’s localization by a simple construction. The probability of localization for positive energy states results to be described by causal positive operator valued (PO-) localizations, which are the traces of the causal localizations on the subspaces of positive energy. These causal Poincaré covariant PO-localizations for every irreducible massive relativistic system were, all the more, not known before. They are shown to be separated. Hence, the positive energy systems can be localized within every open region by a suitable preparation as accurately as desired. Finally, the attempt is made to provide an interpretation of the PO-localization operators within the frame of conventional quantum mechanics attributing an important role to the negative energy states.

  7. Quantum correlations with no causal order

    PubMed Central

    Oreshkov, Ognyan; Costa, Fabio; Brukner, Časlav

    2012-01-01

    The idea that events obey a definite causal order is deeply rooted in our understanding of the world and at the basis of the very notion of time. But where does causal order come from, and is it a necessary property of nature? Here, we address these questions from the standpoint of quantum mechanics in a new framework for multipartite correlations that does not assume a pre-defined global causal structure but only the validity of quantum mechanics locally. All known situations that respect causal order, including space-like and time-like separated experiments, are captured by this framework in a unified way. Surprisingly, we find correlations that cannot be understood in terms of definite causal order. These correlations violate a 'causal inequality' that is satisfied by all space-like and time-like correlations. We further show that in a classical limit causal order always arises, which suggests that space-time may emerge from a more fundamental structure in a quantum-to-classical transition. PMID:23033068

  8. Tractor accidents in Swedish traffic.

    PubMed

    Pinzke, Stefan; Nilsson, Kerstin; Lundqvist, Peter

    2012-01-01

    The objective of this study is to reach a better understanding of accidents on Swedish roads involving tractors and to suggest ways of preventing them. In an earlier study we analyzed police-reported fatal accidents and accidents that led to physical injuries from 1992 to 2005. During each year of this period, tractors were involved in 128 traffic accidents on average, an average of 7 people were killed, 44 sustained serious injuries, and 143 sustained slight injuries. The number of fatalities in these tractor accidents was about 1.3% of all deaths in traffic accidents in Sweden. Cars were most often involved in the tractor accidents (58%) and 15% were single vehicle accidents. The mean age of the tractor driver involved was 39.8 years and young drivers (15-24 years) were overrepresented (30%). We are now increasing the data collected with the years 2006-2010 in order to study the changes in the number of accidents. Special attention will be given to the younger drivers and to single vehicle accidents. Based on the results we aim to develop suggestions for reducing road accidents, e.g. including measures for making farm vehicles more visible and improvement of the training provided at driving schools. PMID:22317543

  9. Perception of causality in schizophrenia spectrum disorder.

    PubMed

    Tschacher, Wolfgang; Kupper, Zeno

    2006-10-01

    Patients with schizophrenia spectrum disorders often maintain deviating views on cause-effect relationships, especially when positive and disorganization symptoms are manifest. Altered perceived causality is prominent in delusional ideation, in ideas of reference, and in the mentalizing ability (theory of mind [ToM]) of patients. Perceiving causal relationships may be understood either as higher order cognitive reasoning or as low-level information processing. In the present study, perception of causality was investigated as a low-level, preattentional capability similar to gestalt-like perceptual organization. Thirty-one patients (24 men and 7 women with mean age 27.7 years) and the same number of healthy control subjects matched to patients with respect to age and sex were tested. A visual paradigm was used in which 2 identical discs move, from opposite sides of a monitor, steadily toward and then past one another. Their coincidence generates an ambiguous, bistable percept (discs either "stream through" or "bounce off" one another). The bouncing perception, ie, perceived causality, is enhanced when auditory stimuli are presented at the time of coincidence. Psychopathology was measured using the Positive and Negative Syndrome Scale. It was found that positive symptoms were strongly associated with increased perceived causality and disorganization with attenuated perceived causality. Patients in general were not significantly different from controls, but symptom subgroups showed specifically altered perceived causality. Perceived causality as a basic preattentional process may contribute to higher order cognitive alterations and ToM deficiencies. It is suggested that cognitive remediation therapy should address both increased and reduced perception of causality. PMID:16896057

  10. A catastrophe-theory model for simulating behavioral accidents

    SciTech Connect

    Souder, W.E.

    1988-01-01

    Behavioral accidents are a particular type of accident. They are caused by inappropriate individual behaviors and faulty reactions. Catastrophe theory is a means for mathematically modeling the dynamic processes that underlie behavioral accidents. Based on a comprehensive data base of mining accidents, a computerized catastrophe model has been developed by the Bureau of Mines. This model systematically links individual psychological, group behavioral, and mine environmental variables with other accident causing factors. It answers several longstanding questions about why some normally safe behaving persons may spontaneously engage in unsafe acts that have high risks of serious injury. Field tests with the model indicate that it has three imnportant uses: it can be used as a effective training aid for increasing employee safety consciousness; it can be used as a management laboratory for testing decision alternatives and policies; and it can be used to help design the most effective work teams.

  11. [Skateboard and rollerskate accidents].

    PubMed

    Lohmann, M; Petersen, A O; Pedersen, O D

    1990-05-28

    The increasing popularity of skateboards and rollerskates has resulted in an increased number of contacts with the casualty department in Denmark after accidents. As part of the Danish share in the EHLASS project (European Home and Leisure Surveillance System), 120,000 consecutive contacts with the casualty departments were reviewed. Out of these 516 were due to accidents with skateboards and rollerskates (181/335). A total of 194 of these injuries (38%) were fractures and 80% of these were in the upper limbs. Twenty fractures required reposition under general anaesthesia and two required osteosynthesis. Nine patients were admitted for observation for concussion. One patient had sustained rupture of the spleen and splenectomy was necessary. A total of 44 patients were admitted. None of the 516 patients had employed protective equipment on the injured region. Considerable reduction in the number of injuries could probably be produced by employment of suitable protective equipment.

  12. Farm accidents in children.

    PubMed

    Cogbill, T H; Busch, H M; Stiers, G R

    1985-10-01

    During a 6 1/2 year period, 105 children were admitted to the hospital as the result of trauma that occurred on farms. The mechanism of injury was animal related in 42 (40%), tractor or wagon accident in 28 (26%), farm machinery in 21 (20%), fall from farm building in six (6%), and miscellaneous in eight (8%). Injury Severity Score was calculated for each patient. An Injury Severity Score of greater than or equal to 25 was determined for 11 children (11%). Life-threatening injuries, therefore, are frequently the result of childhood activities that take place in agricultural environments. The most common injuries were orthopedic, neurologic, thoracoabdominal, and maxillofacial. There was one death in the series, and only one survivor sustained major long-term disability. Such injuries are managed with optimal outcome in a regional trauma center. Educational programs with an emphasis on prevention and safety measures may reduce the incidence of farm accidents. PMID:4047799

  13. On the origin of Hill's causal criteria.

    PubMed

    Morabia, A

    1991-09-01

    The rules to assess causation formulated by the eighteenth century Scottish philosopher David Hume are compared to Sir Austin Bradford Hill's causal criteria. The strength of the analogy between Hume's rules and Hill's causal criteria suggests that, irrespective of whether Hume's work was known to Hill or Hill's predecessors, Hume's thinking expresses a point of view still widely shared by contemporary epidemiologists. The lack of systematic experimental proof to causal inferences in epidemiology may explain the analogy of Hume's and Hill's, as opposed to Popper's, logic.

  14. Causality and methodology. Notes on thanatochronological estimations.

    PubMed

    Boniolo, Giovanni; Libero, Mirella; Aprile, Anna

    2005-01-01

    The authors propose some methodological considerations on thanatochronological estimations. They first consider the problem of the definition of death, and then they deal with the issue of the estimations of death time, that is, with the Post-Mortem Interval (PMI). As regards the first question, they note that it does not concern only the definition of death, but also the choice of a particular kind of definition of 'definition'. With reference to the second question, the authors suggest a causal model showing that the presence of many causal chains must be taken into consideration. Finally they discuss what 'most convenient and reliable causal chain' means for a thanatochronologist.

  15. A significant causal association between C-reactive protein levels and schizophrenia

    PubMed Central

    Inoshita, Masatoshi; Numata, Shusuke; Tajima, Atsushi; Kinoshita, Makoto; Umehara, Hidehiro; Nakataki, Masahito; Ikeda, Masashi; Maruyama, Souichiro; Yamamori, Hidenaga; Kanazawa, Tetsufumi; Shimodera, Shinji; Hashimoto, Ryota; Imoto, Issei; Yoneda, Hiroshi; Iwata, Nakao; Ohmori, Tetsuro

    2016-01-01

    Many observational studies have shown elevated blood CRP levels in schizophrenia compared with controls, and one population-based prospective study has reported that elevated plasma CRP levels were associated with late- and very-late-onset schizophrenia. Furthermore, several clinical studies have reported the efficacy of anti-inflammatory drugs on the symptoms in patients with schizophrenia. However, whether elevated CRP levels are causally related to schizophrenia is not still established because of confounding factors and reverse causality. In the present study, we demonstrated that serum CRP levels were significantly higher in patients with schizophrenia than in the controls by conducting a case-control study and a meta-analysis of case-control studies between schizophrenia and serum CRP levels. Furthermore, we provided evidence for a causal association between elevated CRP levels and increased schizophrenia risk by conducting a Mendelian randomization analysis. Our findings suggest that elevated CRP itself may be a causal risk factor for schizophrenia. PMID:27193331

  16. Accident Flying Squad

    PubMed Central

    Snook, Roger

    1972-01-01

    This paper describes the organization, evaluation, and costing of an independently financed and operated accident flying squad. 132 accidents involving 302 casualties were attended, six deaths were prevented, medical treatment contributed to the survival of a further four, and the condition or comfort of many other casualties was improved. The calls in which survival was influenced were evenly distributed throughout the three-and-a-half-year survey and seven of the 10 so aided were over 16 and under 30 years of age, all 10 being in the working age group. The time taken to provide the service was not excessive and the expense when compared with the overall saving was very small. The scheme was seen to be equally suitable for basing on hospital or general practice or both, and working as an integrated team with the ambulance service. The use of specialized transport was found to be unnecessary. Other benefits of the scheme included use of the experience of attending accidents to ensure relevant and realistic training for emergency service personnel, and an appreciation of the effect of ambulance design on the patient. ImagesFIG. 1FIG. 4 PMID:5069642

  17. Evaluation of severe accident risks: Quantification of major input parameters: MAACS (MELCOR Accident Consequence Code System) input

    SciTech Connect

    Sprung, J.L.; Jow, H-N ); Rollstin, J.A. ); Helton, J.C. )

    1990-12-01

    Estimation of offsite accident consequences is the customary final step in a probabilistic assessment of the risks of severe nuclear reactor accidents. Recently, the Nuclear Regulatory Commission reassessed the risks of severe accidents at five US power reactors (NUREG-1150). Offsite accident consequences for NUREG-1150 source terms were estimated using the MELCOR Accident Consequence Code System (MACCS). Before these calculations were performed, most MACCS input parameters were reviewed, and for each parameter reviewed, a best-estimate value was recommended. This report presents the results of these reviews. Specifically, recommended values and the basis for their selection are presented for MACCS atmospheric and biospheric transport, emergency response, food pathway, and economic input parameters. Dose conversion factors and health effect parameters are not reviewed in this report. 134 refs., 15 figs., 110 tabs.

  18. Fatal aviation accidents in Lower Saxony from 1979 to 1996.

    PubMed

    Ast, F W; Kernbach-Wighton, G; Kampmann, H; Koops, E; Püschel, K; Tröger, H D; Kleemann, W J

    2001-06-01

    So far no national or regional studies have been published in Germany regarding the number of fatal aviation accidents and results of autopsy findings. Therefore, we evaluated all fatal aviation accidents occurring in Lower Saxony from 1979 to 1996. A total of 96 aviation accidents occurred in this period involving 73 aeroplanes. The crashes resulted in the death of 154 people ranging in age from 19 to 68 years. The greatest number of victims in a single crash of an aircraft was (n=7). Other types of fatal accidents were crashes of aircraft and helicopter while on the ground (n=5), hot-air balloons (n=2), parachutes (n=10), hang glider accidents (n=5) and the striking of a bystander by a model airplane. Autopsies were performed on 68 of the 154 victims (44.2%), including 39 of the 73 pilots (53.4%). Some of the autopsies yielded findings relevant to the cause of the accident: gunshot wounds, the presence of alcohol or drugs in blood and preexisting diseases. Our findings emphasize the need for autopsy on all aviation accident victims, especially pilots, as this is the only reliable method to uncover all factors contributing to an accident.

  19. Fatal aviation accidents in Lower Saxony from 1979 to 1996.

    PubMed

    Ast, F W; Kernbach-Wighton, G; Kampmann, H; Koops, E; Püschel, K; Tröger, H D; Kleemann, W J

    2001-06-01

    So far no national or regional studies have been published in Germany regarding the number of fatal aviation accidents and results of autopsy findings. Therefore, we evaluated all fatal aviation accidents occurring in Lower Saxony from 1979 to 1996. A total of 96 aviation accidents occurred in this period involving 73 aeroplanes. The crashes resulted in the death of 154 people ranging in age from 19 to 68 years. The greatest number of victims in a single crash of an aircraft was (n=7). Other types of fatal accidents were crashes of aircraft and helicopter while on the ground (n=5), hot-air balloons (n=2), parachutes (n=10), hang glider accidents (n=5) and the striking of a bystander by a model airplane. Autopsies were performed on 68 of the 154 victims (44.2%), including 39 of the 73 pilots (53.4%). Some of the autopsies yielded findings relevant to the cause of the accident: gunshot wounds, the presence of alcohol or drugs in blood and preexisting diseases. Our findings emphasize the need for autopsy on all aviation accident victims, especially pilots, as this is the only reliable method to uncover all factors contributing to an accident. PMID:11348795

  20. Dark matter perturbations and viscosity: A causal approach

    NASA Astrophysics Data System (ADS)

    Acquaviva, Giovanni; John, Anslyn; Pénin, Aurélie

    2016-08-01

    The inclusion of dissipative effects in cosmic fluids modifies their clustering properties and could have observable effects on the formation of large-scale structures. We analyze the evolution of density perturbations of cold dark matter endowed with causal bulk viscosity. The perturbative analysis is carried out in the Newtonian approximation and the bulk viscosity is described by the causal Israel-Stewart (IS) theory. In contrast to the noncausal Eckart theory, we obtain a third-order evolution equation for the density contrast that depends on three free parameters. For certain parameter values, the density contrast and growth factor in IS mimic their behavior in Λ CDM when z ≥1 . Interestingly, and contrary to intuition, certain sets of parameters lead to an increase of the clustering.

  1. Willingness to use safety belt and levels of injury in car accidents.

    PubMed

    de Lapparent, Matthieu

    2008-05-01

    In this article, we develop a bivariate ordered Probit model to analyze the decision to fasten the safety belt in a car and the resulting severity of accidents if it happens. The approach takes into account the fact that the decision to fasten the safety belt has a direct causal effect on the category of injury if an accident happens. Our application to a sample drawn from the database of French accident reports in 2003 for three populations of car users (drivers, front passengers, rear passengers) shows that fastening the safety belt is significantly related to a decrease in severe injuries but it shows also that these car users compensate partly for this safety benefit. Furthermore, it is observed that demographic characteristics of car users, as well as transport facilities, play important roles in decisions to fasten safety belts and in the eventual resulting accident injuries.

  2. The gravity dual of boundary causality

    NASA Astrophysics Data System (ADS)

    Engelhardt, Netta; Fischetti, Sebastian

    2016-09-01

    In gauge/gravity duality, points which are not causally related on the boundary cannot be causally related through the bulk; this is the statement of boundary causality. By the Gao-Wald theorem, the averaged null energy condition in the bulk is sufficient to ensure this property. Here we proceed in the converse direction: we derive a necessary as well as sufficient condition for the preservation of boundary causality under perturbative (quantum or stringy) corrections to the bulk. The condition that we find is a (background-dependent) constraint on the amount by which light cones can ‘open’ over all null bulk geodesics. We show that this constraint is weaker than the averaged null energy condition.

  3. Risk and causality in newspaper reporting.

    PubMed

    Boholm, Max

    2009-11-01

    The study addresses the textual representation of risk and causality in news media reporting. The analytical framework combines two theoretical perspectives: media frame analysis and the philosophy of causality. Empirical data derive from selected newspaper articles on risks in the Göta älv river valley in southwest Sweden from 1994 to 2007. News media content was coded and analyzed with respect to causal explanations of risk issues. At the level of individual articles, this study finds that the media provide simple causal explanations of risks such as water pollution, landslides, and flooding. Furthermore, these explanations are constructed, or framed, in various ways, the same risk being attributed to different causes in different articles. However, the study demonstrates that a fairly complex picture of risks in the media emerges when extensive material is analyzed systematically.

  4. Rate-Agnostic (Causal) Structure Learning

    PubMed Central

    Plis, Sergey; Danks, David; Freeman, Cynthia; Calhoun, Vince

    2016-01-01

    Causal structure learning from time series data is a major scientific challenge. Extant algorithms assume that measurements occur sufficiently quickly; more precisely, they assume approximately equal system and measurement timescales. In many domains, however, measurements occur at a significantly slower rate than the underlying system changes, but the size of the timescale mismatch is often unknown. This paper develops three causal structure learning algorithms, each of which discovers all dynamic causal graphs that explain the observed measurement data, perhaps given undersampling. That is, these algorithms all learn causal structure in a “rate-agnostic” manner: they do not assume any particular relation between the measurement and system timescales. We apply these algorithms to data from simulations to gain insight into the challenge of undersampling. PMID:27182188

  5. Synergy, redundancy and unnormalized Granger causality.

    PubMed

    Stramaglia, S; Angelini, L; Cortes, J M; Marinazzo, D

    2015-08-01

    We analyze by means of Granger causality the effect of synergy and redundancy in the inference (from time series data) of the information flow between subsystems of a complex network. Whilst fully conditioned Granger causality is not affected by synergy, the pairwise analysis fails to put in evidence synergetic effects. We show that maximization of the total Granger causality to a given target, over all the possible partitions of the set of driving variables, puts in evidence redundant multiplets of variables influencing the target, provided that an unnormalized definition of Granger causality is adopted. Along the same lines we also introduce a pairwise index of synergy (w.r.t. to information flow to a third variable) which is zero when two independent sources additively influence a common target; thus, this definition differs from previous definitions of synergy.

  6. Granger-causality maps of diffusion processes.

    PubMed

    Wahl, Benjamin; Feudel, Ulrike; Hlinka, Jaroslav; Wächter, Matthias; Peinke, Joachim; Freund, Jan A

    2016-02-01

    Granger causality is a statistical concept devised to reconstruct and quantify predictive information flow between stochastic processes. Although the general concept can be formulated model-free it is often considered in the framework of linear stochastic processes. Here we show how local linear model descriptions can be employed to extend Granger causality into the realm of nonlinear systems. This novel treatment results in maps that resolve Granger causality in regions of state space. Through examples we provide a proof of concept and illustrate the utility of these maps. Moreover, by integration we convert the local Granger causality into a global measure that yields a consistent picture for a global Ornstein-Uhlenbeck process. Finally, we recover invariance transformations known from the theory of autoregressive processes. PMID:26986337

  7. Quantum probability assignment limited by relativistic causality

    PubMed Central

    Han, Yeong Deok; Choi, Taeseung

    2016-01-01

    Quantum theory has nonlocal correlations, which bothered Einstein, but found to satisfy relativistic causality. Correlation for a shared quantum state manifests itself, in the standard quantum framework, by joint probability distributions that can be obtained by applying state reduction and probability assignment that is called Born rule. Quantum correlations, which show nonlocality when the shared state has an entanglement, can be changed if we apply different probability assignment rule. As a result, the amount of nonlocality in quantum correlation will be changed. The issue is whether the change of the rule of quantum probability assignment breaks relativistic causality. We have shown that Born rule on quantum measurement is derived by requiring relativistic causality condition. This shows how the relativistic causality limits the upper bound of quantum nonlocality through quantum probability assignment. PMID:26971717

  8. The gravity dual of boundary causality

    NASA Astrophysics Data System (ADS)

    Engelhardt, Netta; Fischetti, Sebastian

    2016-09-01

    In gauge/gravity duality, points which are not causally related on the boundary cannot be causally related through the bulk; this is the statement of boundary causality. By the Gao–Wald theorem, the averaged null energy condition in the bulk is sufficient to ensure this property. Here we proceed in the converse direction: we derive a necessary as well as sufficient condition for the preservation of boundary causality under perturbative (quantum or stringy) corrections to the bulk. The condition that we find is a (background-dependent) constraint on the amount by which light cones can ‘open’ over all null bulk geodesics. We show that this constraint is weaker than the averaged null energy condition.

  9. Granger-causality maps of diffusion processes.

    PubMed

    Wahl, Benjamin; Feudel, Ulrike; Hlinka, Jaroslav; Wächter, Matthias; Peinke, Joachim; Freund, Jan A

    2016-02-01

    Granger causality is a statistical concept devised to reconstruct and quantify predictive information flow between stochastic processes. Although the general concept can be formulated model-free it is often considered in the framework of linear stochastic processes. Here we show how local linear model descriptions can be employed to extend Granger causality into the realm of nonlinear systems. This novel treatment results in maps that resolve Granger causality in regions of state space. Through examples we provide a proof of concept and illustrate the utility of these maps. Moreover, by integration we convert the local Granger causality into a global measure that yields a consistent picture for a global Ornstein-Uhlenbeck process. Finally, we recover invariance transformations known from the theory of autoregressive processes.

  10. Singular clues to causality and their use in human causal judgment.

    PubMed

    White, Peter A

    2014-01-01

    It is argued that causal understanding originates in experiences of acting on objects. Such experiences have consistent features that can be used as clues to causal identification and judgment. These are singular clues, meaning that they can be detected in single instances. A catalog of 14 singular clues is proposed. The clues function as heuristics for generating causal judgments under uncertainty and are a pervasive source of bias in causal judgment. More sophisticated clues such as mechanism clues and repeated interventions are derived from the 14. Research on the use of empirical information and conditional probabilities to identify causes has used scenarios in which several of the clues are present, and the use of empirical association information for causal judgment depends on the presence of singular clues. It is the singular clues and their origin that are basic to causal understanding, not multiple instance clues such as empirical association, contingency, and conditional probabilities. PMID:23957568

  11. Kant on causal laws and powers.

    PubMed

    Henschen, Tobias

    2014-12-01

    The aim of the paper is threefold. Its first aim is to defend Eric Watkins's claim that for Kant, a cause is not an event but a causal power: a power that is borne by a substance, and that, when active, brings about its effect, i.e. a change of the states of another substance, by generating a continuous flow of intermediate states of that substance. The second aim of the paper is to argue against Watkins that the Kantian concept of causal power is not the pre-critical concept of real ground but the category of causality, and that Kant holds with Hume that causal laws cannot be inferred non-inductively (that he accordingly has no intention to show in the Second analogy or elsewhere that events fall under causal laws). The third aim of the paper is to compare the Kantian position on causality with central tenets of contemporary powers ontology: it argues that unlike the variants endorsed by contemporary powers theorists, the Kantian variants of these tenets are resistant to objections that neo-Humeans raise to these tenets. PMID:25571742

  12. Causal Inference for Vaccine Effects on Infectiousness

    PubMed Central

    Halloran, M. Elizabeth; Hudgens, Michael G.

    2012-01-01

    If a vaccine does not protect individuals completely against infection, it could still reduce infectiousness of infected vaccinated individuals to others. Typically, vaccine efficacy for infectiousness is estimated based on contrasts between the transmission risk to susceptible individuals from infected vaccinated individuals compared with that from infected unvaccinated individuals. Such estimates are problematic, however, because they are subject to selection bias and do not have a causal interpretation. Here, we develop causal estimands for vaccine efficacy for infectiousness for four different scenarios of populations of transmission units of size two. These causal estimands incorporate both principal stratification, based on the joint potential infection outcomes under vaccine and control, and interference between individuals within transmission units. In the most general scenario, both individuals can be exposed to infection outside the transmission unit and both can be assigned either vaccine or control. The three other scenarios are special cases of the general scenario where only one individual is exposed outside the transmission unit or can be assigned vaccine. The causal estimands for vaccine efficacy for infectiousness are well defined only within certain principal strata and, in general, are identifiable only with strong unverifiable assumptions. Nonetheless, the observed data do provide some information, and we derive large sample bounds on the causal vaccine efficacy for infectiousness estimands. An example of the type of data observed in a study to estimate vaccine efficacy for infectiousness is analyzed in the causal inference framework we developed. PMID:22499732

  13. Causality violation, gravitational shockwaves and UV completion

    NASA Astrophysics Data System (ADS)

    Hollowood, Timothy J.; Shore, Graham M.

    2016-03-01

    The effective actions describing the low-energy dynamics of QFTs involving gravity generically exhibit causality violations. These may take the form of superluminal propagation or Shapiro time advances and allow the construction of "time machines", i.e. spacetimes admitting closed non-spacelike curves. Here, we discuss critically whether such causality violations may be used as a criterion to identify unphysical effective actions or whether, and how, causality problems may be resolved by embedding the action in a fundamental, UV complete QFT. We study in detail the case of photon scattering in an Aichelburg-Sexl gravitational shockwave background and calculate the phase shifts in QED for all energies, demonstrating their smooth interpolation from the causality-violating effective action values at low-energy to their manifestly causal high-energy limits. At low energies, these phase shifts may be interpreted as backwards-in-time coordinate jumps as the photon encounters the shock wavefront, and we illustrate how the resulting causality problems emerge and are resolved in a two-shockwave time machine scenario. The implications of our results for ultra-high (Planck) energy scattering, in which graviton exchange is modelled by the shockwave background, are highlighted.

  14. The good, the bad, and the timely: how temporal order and moral judgment influence causal selection

    PubMed Central

    Reuter, Kevin; Kirfel, Lara; van Riel, Raphael; Barlassina, Luca

    2014-01-01

    Causal selection is the cognitive process through which one or more elements in a complex causal structure are singled out as actual causes of a certain effect. In this paper, we report on an experiment in which we investigated the role of moral and temporal factors in causal selection. Our results are as follows. First, when presented with a temporal chain in which two human agents perform the same action one after the other, subjects tend to judge the later agent to be the actual cause. Second, the impact of temporal location on causal selection is almost canceled out if the later agent did not violate a norm while the former did. We argue that this is due to the impact that judgments of norm violation have on causal selection—even if the violated norm has nothing to do with the obtaining effect. Third, moral judgments about the effect influence causal selection even in the case in which agents could not have foreseen the effect and did not intend to bring it about. We discuss our findings in connection to recent theories of the role of moral judgment in causal reasoning, on the one hand, and to probabilistic models of temporal location, on the other. PMID:25477851

  15. [Chernobyl nuclear power plant accident and Tokaimura criticality accident].

    PubMed

    Takada, Jun

    2012-03-01

    It is clear from inspection of historical incidents that the scale of disasters in a nuclear power plant accident is quite low level overwhelmingly compared with a nuclear explosion in nuclear war. Two cities of Hiroshima and Nagasaki were destroyed by nuclear blast with about 20 kt TNT equivalent and then approximately 100,000 people have died respectively. On the other hand, the number of acute death is 30 in the Chernobyl nuclear reactor accident. In this chapter, we review health hazards and doses in two historical nuclear incidents of Chernobyl and Tokaimura criticality accident and then understand the feature of the radiation accident in peaceful utilization of nuclear power.

  16. The role of causal criteria in causal inferences: Bradford Hill's "aspects of association"

    PubMed Central

    Ward, Andrew C

    2009-01-01

    As noted by Wesley Salmon and many others, causal concepts are ubiquitous in every branch of theoretical science, in the practical disciplines and in everyday life. In the theoretical and practical sciences especially, people often base claims about causal relations on applications of statistical methods to data. However, the source and type of data place important constraints on the choice of statistical methods as well as on the warrant attributed to the causal claims based on the use of such methods. For example, much of the data used by people interested in making causal claims come from non-experimental, observational studies in which random allocations to treatment and control groups are not present. Thus, one of the most important problems in the social and health sciences concerns making justified causal inferences using non-experimental, observational data. In this paper, I examine one method of justifying such inferences that is especially widespread in epidemiology and the health sciences generally – the use of causal criteria. I argue that while the use of causal criteria is not appropriate for either deductive or inductive inferences, they do have an important role to play in inferences to the best explanation. As such, causal criteria, exemplified by what Bradford Hill referred to as "aspects of [statistical] associations", have an indispensible part to play in the goal of making justified causal claims. PMID:19534788

  17. [Electrophysiologic criteria for the prevention of electric accidents].

    PubMed

    Kupfer, J

    1990-11-01

    About 0.25 percent of all registered industrial accidents are caused by electric current. One in 20 of these accidents has been fatal. The consequences of electric flow are determined by several factors, above all voltage, time and path of flow, type of current, and resistors within the power circuit. These are attributable to physiological criteria of conduction. Slight electric shock and death by ventricular fibrillation are close to each other by the all-or-nothing law. Conclusions are suggested for practice, and a discussion is proposed with a view to find an adequate definition of the power-related accident. PMID:2085034

  18. Neck sprains after road traffic accidents: a modern epidemic.

    PubMed

    Galasko, C S; Murray, P M; Pitcher, M; Chambers, H; Mansfield, S; Madden, M; Jordon, C; Kinsella, A; Hodson, M

    1993-03-01

    This study was carried out to determine the incidence of soft tissue injuries of the cervical spine after road traffic accidents and to assess whether the incidence had changed with time. The results show that there has been a progressive increase since 1982 in the number of patients seen in accident and emergency departments with a neck sprain after road traffic accidents. The results suggest that the increase is not necessarily due to the introduction of seat belts, but that the relentless increasing epidemic may be due to other factors.

  19. [A study on fall accident].

    PubMed

    Lee, H S; Kim, M J

    1997-01-01

    The study was conducted from November 1995 to May 1996 at the one general hospital in Seoul. The total subjects of this study were 412 patients who have the experience of fall accident, among them 31 was who have fallen during hospitalization and 381 was who visited emergency room and out patient clinic. The purposes of this study were to determine the characteristics, risk factors and results of fall accident and to suggest the nursing strategies for prevention of fall. Data were collected by reviewing the medical records and interviewing with the fallers and their family members. For data analysis spss/pc+ program was utilized for descriptive statistics, adjusted standardized X2-test. The results of this study were as follows: 1) Total subjects were 412 fallers, of which 245 (59.5%) were men and 167 (40.5%) were women. Age were 0-14 years 79 (19.2%), 15-44 years 125 (30.4%), 45-64 years 104 (25.2%), over 65 years 104 (25.2%). 2) There was significant association between age and the sexes (X2 = 39.17, P = 0.00). 3) There was significant association between age and history of falls (X2 = 44.41, P = .00). And history of falls in the elderly was significantly associated with falls. 4) There was significant association with age and medical diagnosis (X2 = 140.66, P = .00), chief medical diagnosis were hypertension (34), diabetes mellitus (22), arthritis (11), stroke (8), fracture (7), pulmonary tuberculosis (6), dementia (5) and cataract (5). 5) There was significant association between age and intrinsic factors: cognitive impairment, mobility impairment, insomnia, emotional problems, urinary difficulty, visual impairments, hearing impairments, use of drugs (sedatives, antihypertensive drugs, diuretics, antidepressants) (P < 0.05). But there was no significant association between age and dizziness (X2 = 2.87, P = .41). 6) 15.3% of total fallers were drunken state when they were fallen. 7) Environmental factors of fall accident were unusual posture (50.9%), slips (35

  20. Aircraft accident survivors as witnesses.

    PubMed

    Dodge, R E

    1983-02-01

    This is a study of the reliability of aircrash survivors as witnesses. Some of their statements are compared to known facts at the time of the crash, including the time of the accident and the weather conditions. Other facts are compared between the survivors, such as the mood of the passengers immediately post-crash. The KLM-Pan Am accident in the Canary Islands is used as the study accident. A suggestion for future use of survivors' statements is tendered.

  1. Modeling accident frequencies as zero-altered probability processes: an empirical inquiry.

    PubMed

    Shankar, V; Milton, J; Mannering, F

    1997-11-01

    This paper presents an empirical inquiry into the applicability of zero-altered counting processes to roadway section accident frequencies. The intent of such a counting process is to distinguish sections of roadway that are truly safe (near zero-accident likelihood) from those that are unsafe but happen to have zero accidents observed during the period of observation (e.g. one year). Traditional applications of Poisson and negative binomial accident frequency models do not account for this distinction and thus can produce biased coefficient estimates because of the preponderance of zero-accident observations. Zero-altered probability processes such as the zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) distributions are examined and proposed for accident frequencies by roadway functional class and geographic location. The findings show that the ZIP structure models are promising and have great flexibility in uncovering processes affecting accident frequencies on roadway sections observed with zero accidents and those with observed accident occurrences. This flexibility allows highway engineers to better isolate design factors that contribute to accident occurrence and also provides additional insight into variables that determine the relative accident likelihoods of safe versus unsafe roadways. The generic nature of the models and the relatively good power of the Vuong specification test used in the non-nested hypotheses of model specifications offers roadway designers the potential to develop a global family of models for accident frequency prediction that can be embedded in a larger safety management system. PMID:9370019

  2. Linear structures, causal sets and topology

    NASA Astrophysics Data System (ADS)

    Hudetz, Laurenz

    2015-11-01

    Causal set theory and the theory of linear structures (which has recently been developed by Tim Maudlin as an alternative to standard topology) share some of their main motivations. In view of that, I raise and answer the question how these two theories are related to each other and to standard topology. I show that causal set theory can be embedded into Maudlin's more general framework and I characterise what Maudlin's topological concepts boil down to when applied to discrete linear structures that correspond to causal sets. Moreover, I show that all topological aspects of causal sets that can be described in Maudlin's theory can also be described in the framework of standard topology. Finally, I discuss why these results are relevant for evaluating Maudlin's theory. The value of this theory depends crucially on whether it is true that (a) its conceptual framework is as expressive as that of standard topology when it comes to describing well-known continuous as well as discrete models of spacetime and (b) it is even more expressive or fruitful when it comes to analysing topological aspects of discrete structures that are intended as models of spacetime. On one hand, my theorems support (a). The theory is rich enough to incorporate causal set theory and its definitions of topological notions yield a plausible outcome in the case of causal sets. On the other hand, the results undermine (b). Standard topology, too, has the conceptual resources to capture those topological aspects of causal sets that are analysable within Maudlin's framework. This fact poses a challenge for the proponents of Maudlin's theory to prove it fruitful.

  3. How accurate is accident data in road safety research? An application of vehicle black box data regarding pedestrian-to-taxi accidents in Korea.

    PubMed

    Chung, Younshik; Chang, IlJoon

    2015-11-01

    Recently, the introduction of vehicle black box systems or in-vehicle video event data recorders enables the driver to use the system to collect more accurate crash information such as location, time, and situation at the pre-crash and crash moment, which can be analyzed to find the crash causal factors more accurately. This study presents the vehicle black box system in brief and its application status in Korea. Based on the crash data obtained from the vehicle black box system, this study analyzes the accuracy of the crash data collected from existing road crash data recording method, which has been recorded by police officers based on accident parties' statements or eyewitness's account. The analysis results show that the crash data observed by the existing method have an average of 84.48m of spatial difference and standard deviation of 157.75m as well as average 29.05min of temporal error and standard deviation of 19.24min. Additionally, the average and standard deviation of crash speed errors were found to be 9.03km/h and 7.21km/h, respectively. PMID:26298271

  4. Development and Coherence of Beliefs About Disease Causality and Prevention

    PubMed Central

    Sigelman, Carol K.

    2014-01-01

    Guided by a naïve theories perspective on the development of thinking about disease, this study of 188 children aged 6 to 18 examined knowledge of HIV/AIDS causality and prevention using parallel measures derived from open-ended and structured interviews. Knowledge of both risk factors and prevention rules, as well as conceptual understanding of AIDS causality, increased with age. Younger children displayed more advanced knowledge in response to structured questions than in response to open-ended questions. Contrary to hypothesis, knowledge of causality was not more advanced than knowledge of prevention in elementary school. Moreover, correlations between the two types of knowledge were often nonsignificant except when the same method was used to assess both. Thus, methodology matters in assessing children's knowledge of disease, children's intuitive thinking is not consistently coherent, and it may be safest to educate children explicitly about sound prevention rules rather than assume they will infer the rules themselves from information about a disease's causes. PMID:25584017

  5. Investigating Driver Fatigue versus Alertness Using the Granger Causality Network

    PubMed Central

    Kong, Wanzeng; Lin, Weicheng; Babiloni, Fabio; Hu, Sanqing; Borghini, Gianluca

    2015-01-01

    Driving fatigue has been identified as one of the main factors affecting drivers’ safety. The aim of this study was to analyze drivers’ different mental states, such as alertness and drowsiness, and find out a neurometric indicator able to detect drivers’ fatigue level in terms of brain networks. Twelve young, healthy subjects were recruited to take part in a driver fatigue experiment under different simulated driving conditions. The Electroencephalogram (EEG) signals of the subjects were recorded during the whole experiment and analyzed by using Granger-Causality-based brain effective networks. It was that the topology of the brain networks and the brain’s ability to integrate information changed when subjects shifted from the alert to the drowsy stage. In particular, there was a significant difference in terms of strength of Granger causality (GC) in the frequency domain and the properties of the brain effective network i.e., causal flow, global efficiency and characteristic path length between such conditions. Also, some changes were more significant over the frontal brain lobes for the alpha frequency band. These findings might be used to detect drivers’ fatigue levels, and as reference work for future studies. PMID:26251909

  6. Neural correlates of causality judgment in physical and social context--the reversed effects of space and time.

    PubMed

    Blos, Johannes; Chatterjee, Anjan; Kircher, Tilo; Straube, Benjamin

    2012-11-01

    The perception of causal relationships is crucial to understanding and interacting with our physical and social environment. However, whether the same or different neural processes are involved in perceiving physical and social causality is unknown. Therefore, this study is focused on commonalities and differences in the neural correlates of causality perception in both contexts. During fMRI data-acquisition, participants judged causal relationships of objects in two types of animated video clips (physical/social) with similar manipulations of temporal and spatial stimulus characteristics. Four conditions were analyzed in a two-factorial design [physical causal (PC), physical non-causal (PNC), social causal (SC), social non-causal (SNC)]. We found that higher angles and longer time delays led to decreasing judgments of causality in the physical context, whereas the same manipulations led to increasing judgments in the social context. Instead of a common network for causal judgments (PC>PNC∩SC>SNC), we found a reversed activation pattern for the factors context and judgment. PC and SNC [(PC>PNC)>(SC>SNC)] produced activations in the bilateral insula, the right angular and inferior frontal gyrus and the medial supplementary motor area. PNC and SC [(PC>PNC)<(SC>SNC)] produced activity in medial frontal, left superior temporal and anterior cingulate brain regions. Our data suggest, that the same brain regions contribute to the impression of physical and social causality. However, they demonstrate a reversed activation pattern that reflects the stimulus characteristics of the respective conditions. Thus, specific stimulus characteristics are crucial for the perception of causality.

  7. Factors Associated with Infant Feeding Methods after the Nuclear Power Plant Accident in Fukushima: Data from the Pregnancy and Birth Survey for the Fiscal Year 2011 Fukushima Health Management Survey.

    PubMed

    Ishii, Kayoko; Goto, Aya; Ota, Misao; Yasumura, Seiji; Abe, Masafumi; Fujimori, Keiya

    2016-08-01

    Objectives The objective of this study was to assess the frequency of and factors associated with infant feeding methods after the Fukushima nuclear power plant accident using data from the Fukushima Health Management Survey. Methods We conducted an anonymous self-administered questionnaire survey of 16,001 women who gave birth around the time of the Great East Japan Earthquake and registered their pregnancies at Fukushima Prefecture municipal offices between August 1, 2010 and July 31, 2011. The responses of 8366 women were analyzed. Chi square tests and multiple logistic regression analysis were used to compare various factors between women who had formula-fed their children because of concern regarding radioactive contamination or other reasons and those who had breastfed exclusively. Results The percentage of women who had breastfed exclusively was 30.9 %. The percentage of women who had both breastfed and formula-fed or formula-fed exclusively was 69.1 %, of which 20.3 % formula-fed because of concern regarding radioactive contamination of breast milk. The use of formula feeding because of concern about radioactive contamination was significantly higher in women who had resided within the evacuation area and those whose regular antenatal care had been interrupted. The use of formula feeding for other reasons was significantly higher in women who had resided within the evacuation area and lower for those who had willingly switched to another medical institution. Conclusions for Practice Our results suggest the importance of providing breastfeeding support to women who are forced to evacuate or whose antenatal care is interrupted after a disaster.

  8. Factors Associated with Infant Feeding Methods after the Nuclear Power Plant Accident in Fukushima: Data from the Pregnancy and Birth Survey for the Fiscal Year 2011 Fukushima Health Management Survey.

    PubMed

    Ishii, Kayoko; Goto, Aya; Ota, Misao; Yasumura, Seiji; Abe, Masafumi; Fujimori, Keiya

    2016-08-01

    Objectives The objective of this study was to assess the frequency of and factors associated with infant feeding methods after the Fukushima nuclear power plant accident using data from the Fukushima Health Management Survey. Methods We conducted an anonymous self-administered questionnaire survey of 16,001 women who gave birth around the time of the Great East Japan Earthquake and registered their pregnancies at Fukushima Prefecture municipal offices between August 1, 2010 and July 31, 2011. The responses of 8366 women were analyzed. Chi square tests and multiple logistic regression analysis were used to compare various factors between women who had formula-fed their children because of concern regarding radioactive contamination or other reasons and those who had breastfed exclusively. Results The percentage of women who had breastfed exclusively was 30.9 %. The percentage of women who had both breastfed and formula-fed or formula-fed exclusively was 69.1 %, of which 20.3 % formula-fed because of concern regarding radioactive contamination of breast milk. The use of formula feeding because of concern about radioactive contamination was significantly higher in women who had resided within the evacuation area and those whose regular antenatal care had been interrupted. The use of formula feeding for other reasons was significantly higher in women who had resided within the evacuation area and lower for those who had willingly switched to another medical institution. Conclusions for Practice Our results suggest the importance of providing breastfeeding support to women who are forced to evacuate or whose antenatal care is interrupted after a disaster. PMID:27028325

  9. The impact of outcome valence on the susceptibility to suggestion for post-event causal misinformation.

    PubMed

    Chrobak, Quin M; Groves, Chris L; Otradovec, Tony

    2016-01-01

    Recent research has demonstrated that people are especially susceptible to false memory development for suggested misinformation that fills a causal role (i.e., explains some known outcome) (Chrobak & Zaragoza, 2013). However, little is known about how factors associated with the witnessed outcome impact the likelihood of false memory development. In the present study, outcome valence (negative, positive, or neutral) was manipulated. Participants heard several short stories that contained an outcome (e.g., a counselor getting promoted) that lacked a causal explanation. Participants were subsequently exposed to suggested causal misinformation that explained that outcome (e.g., the counselor performed an impressive act the previous day) and then were tested on their memory for the original event. Results indicated that participants incorrectly reported the suggested causal information more when it explained either a positive or negative outcome as opposed to a neutral outcome. Theoretical and practical implications of these findings are discussed. PMID:26786731

  10. Rear-end accident victims. Importance of understanding the accident.

    PubMed Central

    Sehmer, J. M.

    1993-01-01

    Family physicians regularly treat victims of rear-end vehicle accidents. This article describes how taking a detailed history of the accident and understanding the significance of the physical events is helpful in understanding and anticipating patients' morbidity and clinical course. Eight questions to ask patients are suggested to help physicians understand the severity of injury. PMID:8495140

  11. Radiation accident grips Goiania

    SciTech Connect

    Roberts, L.

    1987-11-20

    On 13 September two young scavengers in Goiania, Brazil, removed a stainless steel cylinder from a cancer therapy machine in an abandoned clinic, touching off a radiation accident second only to Chernobyl in its severity. On 18 September they sold the cylinder, the size of a 1-gallon paint can, to a scrap dealer for $25. At the junk yard an employee dismantled the cylinder and pried open the platinum capsule inside to reveal a glowing blue salt-like substance - 1400 curies of cesium-137. Fascinated by the luminescent powder, several people took it home with them. Some children reportedly rubbed in on their bodies like carnival glitter - an eerie image of how wrong things can go when vigilance over radioactive materials lapses. In all, 244 people in Goiania, a city of 1 million in central Brazil, were contaminated. The eventual toll, in terms of cancer or genetic defects, cannot yet be estimated. Parts of the city are cordoned off as radiation teams continue washing down buildings and scooping up radioactive soil. The government is also grappling with the political fallout from the accident.

  12. Statistical analysis of sudden chemical leakage accidents reported in China between 2006 and 2011.

    PubMed

    Li, Yang; Ping, Hua; Ma, Zhi-Hong; Pan, Li-Gang

    2014-04-01

    According to the data from authoritative sources, 1,400 sudden leakage accidents occurred in China during 2006 to 2011 were investigated, in which, 666 accidents were used for statistical characteristic abstracted with no or little damage. The research results were as follows: (1) Time fluctuation: the yearly number of sudden leakage accidents is shown to be decreasing from 2006 to 2010, and a slightly increase in 2011. Sudden leakage accidents occur mainly in summer, and more than half of the accidents occur from May to September. (2) Regional distribution: the accidents are highly concentrated in the coastal area, in which accidents result from small and medium-sized enterprises more easily than that of the larger ones. (3) Pollutants: hazardous chemicals are up to 95 % of sudden leakage accidents. (4) Steps: transportation represents almost half of the accidents, followed by production, usage, storage, and discard. (5) Pollution and casualties: it is easy to cause environmental pollution and casualties. (6) Causes: more than half of the cases were caused by human factor, followed by management reason, and equipment failure. However, sudden chemical leakage may also be caused by high temperature, rain, wet road, and terrain. (7) The results of principal component analysis: five factors are extracted by the principal component analysis, including pollution, casualties, regional distribution, steps, and month. According to the analysis of the accident, the characteristics, causes, and damages of the sudden leakage accident will be investigated. Therefore, advices for prevention and rescue should be acquired. PMID:24407779

  13. Singular Clues to Causality and Their Use in Human Causal Judgment

    ERIC Educational Resources Information Center

    White, Peter A.

    2014-01-01

    It is argued that causal understanding originates in experiences of acting on objects. Such experiences have consistent features that can be used as clues to causal identification and judgment. These are singular clues, meaning that they can be detected in single instances. A catalog of 14 singular clues is proposed. The clues function as…

  14. The Cradle of Causal Reasoning: Newborns' Preference for Physical Causality

    ERIC Educational Resources Information Center

    Mascalzoni, Elena; Regolin, Lucia; Vallortigara, Giorgio; Simion, Francesca

    2013-01-01

    Perception of mechanical (i.e. physical) causality, in terms of a cause-effect relationship between two motion events, appears to be a powerful mechanism in our daily experience. In spite of a growing interest in the earliest causal representations, the role of experience in the origin of this sensitivity is still a matter of dispute. Here, we…

  15. Dimensions of Causal Understanding: The Role of Complex Causal Models in Students' Understanding of Science

    ERIC Educational Resources Information Center

    Perkins, David N.; Grotzer, Tina A.

    2005-01-01

    This article argues that an important source of the difficulties posed by particular concepts and theories is the narrow range of "types of causal models" with which most learners are familiar. Most learners are familiar with relatively simple styles of causal models, but many concepts and theories in science depend on styles substantially more…

  16. The Mental Representation of Causal Conditional Reasoning: Mental Models or Causal Models

    ERIC Educational Resources Information Center

    Ali, Nilufa; Chater, Nick; Oaksford, Mike

    2011-01-01

    In this paper, two experiments are reported investigating the nature of the cognitive representations underlying causal conditional reasoning performance. The predictions of causal and logical interpretations of the conditional diverge sharply when inferences involving "pairs" of conditionals--such as "if P[subscript 1] then Q" and "if P[subscript…

  17. Insomnia and accidents: cross-sectional study (EQUINOX) on sleep-related home, work and car accidents in 5293 subjects with insomnia from 10 countries.

    PubMed

    Léger, Damien; Bayon, Virginie; Ohayon, Maurice M; Philip, Pierre; Ement, Philippe; Metlaine, Arnaud; Chennaoui, Mounir; Faraut, Brice

    2014-04-01

    The link between sleepiness and the risk of motor vehicle accidents is well known, but little is understood regarding the risk of home, work and car accidents of subjects with insomnia. An international cross-sectional survey was conducted across 10 countries in a population of subjects with sleep disturbances. Primary care physicians administered a questionnaire that included assessment of sociodemographic characteristics, sleep disturbance and accidents (motor vehicle, work and home) related to sleep problems to each subject. Insomnia was defined using the International Classification of Sleep Disorders (ICSD-10) criteria. A total of 5293 subjects were included in the study, of whom 20.9% reported having had at least one home accident within the past 12 months, 10.1% at least one work accident, 9% reported having fallen asleep while driving at least once and 4.1% reported having had at least one car accident related to their sleepiness. All types of accident were reported more commonly by subjects living in urban compared to other residential areas. Car accidents were reported more commonly by employed subjects, whereas home injuries were reported more frequently by the unemployed. Car accidents were reported more frequently by males than by females, whereas home accidents were reported more commonly by females. Patients with insomnia have high rates of home accidents, car accidents and work accidents related to sleep disturbances independently of any adverse effects of hypnotic treatments. Reduced total sleep time may be one factor explaining the high risk of accidents in individuals who complain of insomnia. PMID:24237855

  18. Insomnia and accidents: cross-sectional study (EQUINOX) on sleep-related home, work and car accidents in 5293 subjects with insomnia from 10 countries.

    PubMed

    Léger, Damien; Bayon, Virginie; Ohayon, Maurice M; Philip, Pierre; Ement, Philippe; Metlaine, Arnaud; Chennaoui, Mounir; Faraut, Brice

    2014-04-01

    The link between sleepiness and the risk of motor vehicle accidents is well known, but little is understood regarding the risk of home, work and car accidents of subjects with insomnia. An international cross-sectional survey was conducted across 10 countries in a population of subjects with sleep disturbances. Primary care physicians administered a questionnaire that included assessment of sociodemographic characteristics, sleep disturbance and accidents (motor vehicle, work and home) related to sleep problems to each subject. Insomnia was defined using the International Classification of Sleep Disorders (ICSD-10) criteria. A total of 5293 subjects were included in the study, of whom 20.9% reported having had at least one home accident within the past 12 months, 10.1% at least one work accident, 9% reported having fallen asleep while driving at least once and 4.1% reported having had at least one car accident related to their sleepiness. All types of accident were reported more commonly by subjects living in urban compared to other residential areas. Car accidents were reported more commonly by employed subjects, whereas home injuries were reported more frequently by the unemployed. Car accidents were reported more frequently by males than by females, whereas home accidents were reported more commonly by females. Patients with insomnia have high rates of home accidents, car accidents and work accidents related to sleep disturbances independently of any adverse effects of hypnotic treatments. Reduced total sleep time may be one factor explaining the high risk of accidents in individuals who complain of insomnia.

  19. Causal impressions: predicting when, not just whether.

    PubMed

    Young, Michael E; Rogers, Ester T; Beckmann, Joshua S

    2005-03-01

    In 1739, David Hume established the so-called cues to causality--environmental cues that are important to the inference of causality. Although this descriptive account has been corroborated experimentally, it has not been established why these cues are useful, except that they may reflect statistical regularities in the environment. One of the cues to causality, covariation, helps predict whether an effect will occur, but not its time of occurrence. In the present study, evidence is provided that spatial and temporal contiguity improve an observer's ability to predict when an effect will occur, thus complementing the utility of covariation as a predictor of whether an effect will occur. While observing Michotte's (1946/1963) launching effect, participants showed greater accuracy and precision in their predictions of the onset of movement by the launched object when there was spatial and temporal contiguity. Furthermore, when auditory cues that bridged a delayed launch were included, causal ratings and predictability were similarly affected. These results suggest that the everyday inference of causality relies on our ability to predict whether and when an effect will occur.

  20. Causal conjunction fallacies: the roles of causal strength and mental resources.

    PubMed

    Crisp, Aimée Kay; Feeney, Aidan

    2009-12-01

    In two experiments we tested the prediction derived from Tversky and Kahneman's (1983) work on the causal conjunction fallacy that the strength of the causal connection between constituent events directly affects the magnitude of the causal conjunction fallacy. We also explored whether any effects of perceived causal strength were due to graded output from heuristic Type 1 reasoning processes or the result of analytic Type 2 reasoning processes. As predicted, Experiment 1 demonstrated that fallacy rates were higher for strongly than for weakly related conjunctions. Weakly related conjunctions in turn attracted higher rates of fallacious responding than did unrelated conjunctions. Experiment 2 showed that a concurrent memory load increased rates of fallacious responding for strongly related but not for weakly related conjunctions. We interpret these results as showing that manipulations of the strength of the perceived causal relationship between the conjuncts result in graded output from heuristic reasoning process and that additional mental resources are required to suppress strong heuristic output.

  1. A Causal Relationship of Occupational Stress among University Employees

    PubMed Central

    KAEWANUCHIT, Chonticha; MUNTANER, Carles; ISHA, Nizam

    2015-01-01

    Background: Occupational stress is a psychosocial dimension of occupational health concept on social determinants of health, especially, job & environmental condition. Recently, staff network of different government universities of Thailand have called higher education commission, and Ministry of Education, Thailand to resolve the issue of government education policy (e.g. wage inequity, poor welfare, law, and job & environment condition) that leads to their job insecurity, physical and mental health problems from occupational stress. The aim of this study was to investigate a causal relationship of occupational stress among the academic university employees. Methods: This cross sectional research was conducted in 2014 among 2,000 academic university employees at Thai government universities using stratified random sampling. Independent variables were wage, family support, periods of duty, and job & environmental condition. Dependent variable was stress. Results: Job & environmental condition, as social and environmental factor, and periods of duty as individual factor had direct effect to stress (P< 0.05). Family support, as family factor, and wage, as individual factor had direct effect to stress (P < 0.05). Both family support and wage were the causal endogenous variables. Conclusion: Job & environmental condition and periods of duty were increased so that it associated with occupational stress among academic university employees at moderate level. PMID:26576371

  2. Bus accident analysis of routes with/without bus priority.

    PubMed

    Goh, Kelvin Chun Keong; Currie, Graham; Sarvi, Majid; Logan, David

    2014-04-01

    This paper summarises findings on road safety performance and bus-involved accidents in Melbourne along roads where bus priority measures had been applied. Results from an empirical analysis of the accident types revealed significant reduction in the proportion of accidents involving buses hitting stationary objects and vehicles, which suggests the effect of bus priority in addressing manoeuvrability issues for buses. A mixed-effects negative binomial (MENB) regression and back-propagation neural network (BPNN) modelling of bus accidents considering wider influences on accident rates at a route section level also revealed significant safety benefits when bus priority is provided. Sensitivity analyses done on the BPNN model showed general agreement in the predicted accident frequency between both models. The slightly better performance recorded by the MENB model results suggests merits in adopting a mixed effects modelling approach for accident count prediction in practice given its capability to account for unobserved location and time-specific factors. A major implication of this research is that bus priority in Melbourne's context acts to improve road safety and should be a major consideration for road management agencies when implementing bus priority and road schemes.

  3. German aircraft accident statistics, 1930

    NASA Technical Reports Server (NTRS)

    Weitzmann, Ludwig

    1932-01-01

    The investigation of all serious accidents, involving technical defects in the airplane or engine, is undertaken by the D.V.L. in conjunction with the imperial traffic minister and other interested parties. All accidents not clearly explained in the reports are subsequently cleared up.

  4. First Responders and Criticality Accidents

    SciTech Connect

    Valerie L. Putman; Douglas M. Minnema

    2005-11-01

    Nuclear criticality accident descriptions typically include, but do not focus on, information useful to first responders. We studied these accidents, noting characteristics to help (1) first responders prepare for such an event and (2) emergency drill planners develop appropriate simulations for training. We also provide recommendations to help people prepare for such events in the future.

  5. Causal Phenotype Discovery via Deep Networks

    PubMed Central

    Kale, David C.; Che, Zhengping; Bahadori, Mohammad Taha; Li, Wenzhe; Liu, Yan; Wetzel, Randall

    2015-01-01

    The rapid growth of digital health databases has attracted many researchers interested in using modern computational methods to discover and model patterns of health and illness in a research program known as computational phenotyping. Much of the work in this area has focused on traditional statistical learning paradigms, such as classification, prediction, clustering, pattern mining. In this paper, we propose a related but different paradigm called causal phenotype discovery, which aims to discover latent representations of illness that are causally predictive. We illustrate this idea with a two-stage framework that combines the latent representation learning power of deep neural networks with state-of-the-art tools from causal inference. We apply this framework to two large ICU time series data sets and show that it can learn features that are predictively useful, that capture complex physiologic patterns associated with critical illnesses, and that are potentially more clinically meaningful than manually designed features. PMID:26958203

  6. Normalizing the causality between time series

    NASA Astrophysics Data System (ADS)

    Liang, X. San

    2015-08-01

    Recently, a rigorous yet concise formula was derived to evaluate information flow, and hence the causality in a quantitative sense, between time series. To assess the importance of a resulting causality, it needs to be normalized. The normalization is achieved through distinguishing a Lyapunov exponent-like, one-dimensional phase-space stretching rate and a noise-to-signal ratio from the rate of information flow in the balance of the marginal entropy evolution of the flow recipient. It is verified with autoregressive models and applied to a real financial analysis problem. An unusually strong one-way causality is identified from IBM (International Business Machines Corporation) to GE (General Electric Company) in their early era, revealing to us an old story, which has almost faded into oblivion, about "Seven Dwarfs" competing with a giant for the mainframe computer market.

  7. The causal meaning of Hamilton's rule.

    PubMed

    Okasha, Samir; Martens, Johannes

    2016-03-01

    Hamilton's original derivation of his rule for the spread of an altruistic gene (rb>c) assumed additivity of costs and benefits. Recently, it has been argued that an exact version of the rule holds under non-additive pay-offs, so long as the cost and benefit terms are suitably defined, as partial regression coefficients. However, critics have questioned both the biological significance and the causal meaning of the resulting rule. This paper examines the causal meaning of the generalized Hamilton's rule in a simple model, by computing the effect of a hypothetical experiment to assess the cost of a social action and comparing it to the partial regression definition. The two do not agree. A possible way of salvaging the causal meaning of Hamilton's rule is explored, by appeal to R. A. Fisher's 'average effect of a gene substitution'.

  8. Causal binding of actions to their effects.

    PubMed

    Buehner, Marc J; Humphreys, Gruffydd R

    2009-10-01

    According to widely held views in cognitive science harking back to David Hume, causality cannot be perceived directly, but instead is inferred from patterns of sensory experience, and the quality of these inferences is determined by perceivable quantities such as contingency and contiguity. We report results that suggest a reversal of Hume's conjecture: People's sense of time is warped by the experience of causality. In a stimulus-anticipation task, participants' response behavior reflected a shortened experience of time in the case of target stimuli participants themselves had generated, relative to equidistant, equally predictable stimuli they had not caused. These findings suggest that causality in the mind leads to temporal binding of cause and effect, and extend and generalize beyond earlier claims of intentional binding between action and outcome.

  9. The causal meaning of Hamilton's rule.

    PubMed

    Okasha, Samir; Martens, Johannes

    2016-03-01

    Hamilton's original derivation of his rule for the spread of an altruistic gene (rb>c) assumed additivity of costs and benefits. Recently, it has been argued that an exact version of the rule holds under non-additive pay-offs, so long as the cost and benefit terms are suitably defined, as partial regression coefficients. However, critics have questioned both the biological significance and the causal meaning of the resulting rule. This paper examines the causal meaning of the generalized Hamilton's rule in a simple model, by computing the effect of a hypothetical experiment to assess the cost of a social action and comparing it to the partial regression definition. The two do not agree. A possible way of salvaging the causal meaning of Hamilton's rule is explored, by appeal to R. A. Fisher's 'average effect of a gene substitution'. PMID:27069669

  10. A Cross-Cultural Validation of Perceived Locus of Causality Scale in Physical Education Context

    ERIC Educational Resources Information Center

    Wang, C. K. John; Hagger, Martin; Liu, Woon Chia

    2009-01-01

    We examined the validity of the factor structure and invariance of the Perceived Locus of Causality (PLOC) scale instrument scores across two nations endorsing collectivist (Singapore) and individualist (Great Britain) cultural values. Results indicated that confirmatory factor analytic models of the PLOC exhibited adequate ft according to…

  11. Transport aircraft accident dynamics

    NASA Technical Reports Server (NTRS)

    Cominsky, A.

    1982-01-01

    A study was carried out of 112 impact survivable jet transport aircraft accidents (world wide) of 27,700 kg (60,000 lb.) aircraft and up extending over the last 20 years. This study centered on the effect of impact and the follow-on events on aircraft structures and was confined to the approach, landing and takeoff segments of the flight. The significant characteristics, frequency of occurrence and the effect on the occupants of the above data base were studied and categorized with a view to establishing typical impact scenarios for use as a basis of verifying the effectiveness of potential safety concepts. Studies were also carried out of related subjects such as: (1) assessment of advanced materials; (2) human tolerance to impact; (3) merit functions for safety concepts; and (4) impact analysis and test methods.

  12. On causality in polymer scalar field theory

    NASA Astrophysics Data System (ADS)

    García-Chung, Angel A.; Morales-Técotl, Hugo A.

    2011-10-01

    The properties of spacetime corresponding to a proposed quantum gravity theory might modify the high energy behavior of quantum fields. Motivated by loop quantum gravity, recently, Hossain et al [1] have considered a polymer field algebra that replaces the standard canonical one in order to calculate the propagator of a real scalar field in flat spacetime. This propagator features Lorentz violations. Motivated by the relation between Lorentz invariance and causality in standard Quantum Field Theory, in this work we investigate the causality behavior of the polymer scalar field.

  13. Vehicle accidents related to sleep: a review

    PubMed Central

    Horne, J.; Reyner, L.

    1999-01-01

    Falling asleep while driving accounts for a considerable proportion of vehicle accidents under monotonous driving conditions. Many of these accidents are related to work--for example, drivers of lorries, goods vehicles, and company cars. Time of day (circadian) effects are profound, with sleepiness being particularly evident during night shift work, and driving home afterwards. Circadian factors are as important in determining driver sleepiness as is the duration of the drive, but only duration of the drive is built into legislation protecting professional drivers. Older drivers are also vulnerable to sleepiness in the mid-afternoon. Possible pathological causes of driver sleepiness are discussed, but there is little evidence that this factor contributes greatly to the accident statistics. Sleep does not occur spontaneously without warning. Drivers falling asleep are unlikely to recollect having done so, but will be aware of the precursory state of increasing sleepiness; probably reaching a state of fighting off sleep before an accident. Self awareness of sleepiness is a better method for alerting the driver than automatic sleepiness detectors in the vehicle. None of these have been proved to be reliable and most have shortcomings. Putative counter measures to sleepiness, adopted during continued driving (cold air, use of car radio) are only effective for a short time. The only safe counter measure to driver sleepiness, particularly when the driver reaches the stage of fighting sleep, is to stop driving, and--for example, take a 30 minute break encompassing a short (< 15 minute) nap or coffee (about 150 mg caffeine), which are very effective particularly if taken together. Exercise is of little use. CONCLUSIONS: More education of employers and employees is needed about planning journeys, the dangers of driving while sleepy, and driving at vulnerable times of the day.   PMID:10472301

  14. Domain-specific perceptual causality in children depends on the spatio-temporal configuration, not motion onset.

    PubMed

    Schlottmann, Anne; Cole, Katy; Watts, Rhianna; White, Marina

    2013-01-01

    Humans, even babies, perceive causality when one shape moves briefly and linearly after another. Motion timing is crucial in this and causal impressions disappear with short delays between motions. However, the role of temporal information is more complex: it is both a cue to causality and a factor that constrains processing. It affects ability to distinguish causality from non-causality, and social from mechanical causality. Here we study both issues with 3- to 7-year-olds and adults who saw two computer-animated squares and chose if a picture of mechanical, social or non-causality fit each event best. Prior work fit with the standard view that early in development, the distinction between the social and physical domains depends mainly on whether or not the agents make contact, and that this reflects concern with domain-specific motion onset, in particular, whether the motion is self-initiated or not. The present experiments challenge both parts of this position. In Experiments 1 and 2, we showed that not just spatial, but also animacy and temporal information affect how children distinguish between physical and social causality. In Experiments 3 and 4 we showed that children do not seem to use spatio-temporal information in perceptual causality to make inferences about self- or other-initiated motion onset. Overall, spatial contact may be developmentally primary in domain-specific perceptual causality in that it is processed easily and is dominant over competing cues, but it is not the only cue used early on and it is not used to infer motion onset. Instead, domain-specific causal impressions may be automatic reactions to specific perceptual configurations, with a complex role for temporal information. PMID:23874308

  15. An Analysis of U.S. Civil Rotorcraft Accidents by Cost and Injury (1990-1996)

    NASA Technical Reports Server (NTRS)

    Iseler, Laura; DeMaio, Joe; Rutkowski, Michael (Technical Monitor)

    2002-01-01

    A study of rotorcraft accidents was conducted to identify safety issues and research areas that might lead to a reduction in rotorcraft accidents and fatalities. The primary source of data was summaries of National Transportation Safety Board (NTSB) accident reports. From 1990 to 1996, the NTSB documented 1396 civil rotorcraft accidents in the United States in which 491 people were killed. The rotorcraft data were compared to airline and general aviation data to determine the relative safety of rotorcraft compared to other segments of the aviation industry. In depth analysis of the rotorcraft data addressed demographics, mission, and operational factors. Rotorcraft were found to have an accident rate about ten times that of commercial airliners and about the same as that of general aviation. The likelihood that an accident would be fatal was about equal for all three classes of operation. The most dramatic division in rotorcraft accidents is between flights flown by private pilots versus professional pilots. Private pilots, flying low cost aircraft in benign environments, have accidents that are due, in large part, to their own errors. Professional pilots, in contrast, are more likely to have accidents that are a result of exacting missions or use of specialized equipment. For both groups judgement error is more likely to lead to a fatal accident than are other types of causes. Several approaches to improving the rotorcraft accident rate are recommended. These mostly address improvement in the training of new pilots and improving the safety awareness of private pilots.

  16. Mendelian Randomization for the Identification of Causal Pathways in Atherosclerotic Vascular Disease.

    PubMed

    Jansen, Henning; Lieb, Wolfgang; Schunkert, Heribert

    2016-02-01

    Epidemiological and clinical studies have identified many physiological traits and biomarkers that are statistically associated with coronary artery disease (CAD). For some of these traits and biomarkers it is well established that they represent true causal risk factors for CAD. For other biomarkers, however, the distinct character of association is still a matter of debate. Randomized controlled trials (RCT) had a pivotal role in establishing causal associations between risk factors and biomarkers and CAD in some settings by demonstrating that therapeutic intervention targeting risk factors/biomarkers also affect the risk for clinical outcomes, such as CAD. In other scenarios, however, RCTs did not demonstrate clear benefits associated with lowering biomarker levels and therefore suggest that the association between these biomarkers (like C reactive protein) and CAD was driven by confounding or reverse causation. Even accurately conducted RCTs are not immune against incorrect causal inference. Moreover, the extensive costs and efforts required to conduct RCTs asked for alternative study designs to elucidate potential causal associations. Mendelian Randomization studies represent one such alternative by using genetic variants as proxies for specific biomarkers to investigate potential causal relations between biomarkers and clinical outcomes. In this review, we briefly describe the principles of MR studies and summarize recent MR studies in the context of CAD. PMID:26791863

  17. Pride and Prejudice and Causal Indicators

    ERIC Educational Resources Information Center

    Lee, Nick; Chamberlain, Laura

    2016-01-01

    Aguirre-Urreta, Rönkkö, and Marakas' (2016) paper in "Measurement: Interdisciplinary Research and Perspectives" (hereafter referred to as ARM2016) is an important and timely piece of scholarship, in that it provides strong analytic support to the growing theoretical literature that questions the underlying ideas behind causal and…

  18. Comments: Causal Interpretations of Mediation Effects

    ERIC Educational Resources Information Center

    Jo, Booil; Stuart, Elizabeth A.

    2012-01-01

    The authors thank Dr. Lindsay Page for providing a nice illustration of the use of the principal stratification framework to define causal effects, and a Bayesian model for effect estimation. They hope that her well-written article will help expose education researchers to these concepts and methods, and move the field of mediation analysis in…

  19. Escaping Myopia: Teaching Students about Historical Causality

    ERIC Educational Resources Information Center

    Waring, Scott M.

    2010-01-01

    There are so many aspects to teaching history that are vital to creating well-rounded historical thinkers, but one of the most fundamental and most overlooked elements is the idea of causality. Far too many students do not understand the idea of causation, that there are multiple reasons for why historical events occurred and transpired in the way…

  20. Causality and Teleology in High School Biology.

    ERIC Educational Resources Information Center

    Tamir, Pinchas

    1985-01-01

    Ability to distinguish between causal (cause-effect) and teleological (means-ends) explanations was measured in 1905 twelfth-grade biology students and found to be dependent on student knowledge. Although the inability to make these distinctions contributes to misconceptions in biology, appropriate instruction can easily remedy the problem. Sample…

  1. Inductive Reasoning about Causally Transmitted Properties

    ERIC Educational Resources Information Center

    Shafto, Patrick; Kemp, Charles; Bonawitz, Elizabeth Baraff; Coley, John D.; Tenenbaum, Joshua B.

    2008-01-01

    Different intuitive theories constrain and guide inferences in different contexts. Formalizing simple intuitive theories as probabilistic processes operating over structured representations, we present a new computational model of category-based induction about causally transmitted properties. A first experiment demonstrates undergraduates'…

  2. Marriage and Anomie: A Causal Argument

    ERIC Educational Resources Information Center

    Lee, Gary R.

    1974-01-01

    A sample of 394 married couples is employed to test the possibility of an association between marital satisfaction and personal (attitudinal) anomie. The hypothesis is supported. Conclusions are offered relevant to anomie theory, and to utilization of marital and family phenomena as independent variables in causal explanations of nonfamily events.…

  3. Causal Measurement Models: Can Criticism Stimulate Clarification?

    ERIC Educational Resources Information Center

    Markus, Keith A.

    2016-01-01

    In their 2016 work, Aguirre-Urreta et al. provided a contribution to the literature on causal measurement models that enhances clarity and stimulates further thinking. Aguirre-Urreta et al. presented a form of statistical identity involving mapping onto the portion of the parameter space involving the nomological net, relationships between the…

  4. THE CHILD'S CONCEPTION OF PHYSICAL CAUSALITY.

    ERIC Educational Resources Information Center

    PIAGET, JEAN

    THE CHILD'S CONCEPTION OF PHYSICAL CAUSALITY WAS INVESTIGATED. THREE METHODS OF INVESTIGATION WERE USED. THE FIRST METHOD WAS PURELY VERBAL, AND CONSISTED OF A SERIES OF QUESTIONS DIRECTED TO CHILDREN, REGARDING SOME NATURAL PHENOMENON. THE SECOND METHOD INVOLVED A HALF-VERBAL, HALF-PRACTICAL APPROACH, WHEREIN A SPECIFIC REFERENCE TO NATURAL…

  5. A Quantum Probability Model of Causal Reasoning

    PubMed Central

    Trueblood, Jennifer S.; Busemeyer, Jerome R.

    2012-01-01

    People can often outperform statistical methods and machine learning algorithms in situations that involve making inferences about the relationship between causes and effects. While people are remarkably good at causal reasoning in many situations, there are several instances where they deviate from expected responses. This paper examines three situations where judgments related to causal inference problems produce unexpected results and describes a quantum inference model based on the axiomatic principles of quantum probability theory that can explain these effects. Two of the three phenomena arise from the comparison of predictive judgments (i.e., the conditional probability of an effect given a cause) with diagnostic judgments (i.e., the conditional probability of a cause given an effect). The third phenomenon is a new finding examining order effects in predictive causal judgments. The quantum inference model uses the notion of incompatibility among different causes to account for all three phenomena. Psychologically, the model assumes that individuals adopt different points of view when thinking about different causes. The model provides good fits to the data and offers a coherent account for all three causal reasoning effects thus proving to be a viable new candidate for modeling human judgment. PMID:22593747

  6. Constructing Causal Diagrams to Learn Deliberation

    ERIC Educational Resources Information Center

    Easterday, Matthew W.; Aleven, Vincent; Scheines, Richard; Carver, Sharon M.

    2009-01-01

    Policy problems like "What should we do about global warming?" are ill-defined in large part because we do not agree on a system to represent them the way we agree Algebra problems should be represented by equations. As a first step toward building a policy deliberation tutor, we investigated: (a) whether causal diagrams help students learn to…

  7. Strong curvature singularities and causal simplicity

    SciTech Connect

    Krolak, A. )

    1992-02-01

    Techniques of differential topology in Lorentzian manifolds developed by Geroch, Hawking, and Penrose are used to rule out a class of locally naked strong curvature singularities in strongly causal space-times. This result yields some support to the validity of Penrose's strong cosmic censorship hypothesis.

  8. Linear Response Laws and Causality in Electrodynamics

    ERIC Educational Resources Information Center

    Yuffa, Alex J.; Scales, John A.

    2012-01-01

    Linear response laws and causality (the effect cannot precede the cause) are of fundamental importance in physics. In the context of classical electrodynamics, students often have a difficult time grasping these concepts because the physics is obscured by the intermingling of the time and frequency domains. In this paper, we analyse the linear…

  9. Time and Order Effects on Causal Learning

    ERIC Educational Resources Information Center

    Alvarado, Angelica; Jara, Elvia; Vila, Javier; Rosas, Juan M.

    2006-01-01

    Five experiments were conducted to explore trial order and retention interval effects upon causal predictive judgments. Experiment 1 found that participants show a strong effect of trial order when a stimulus was sequentially paired with two different outcomes compared to a condition where both outcomes were presented intermixed. Experiment 2…

  10. Income inequality and health: a causal review.

    PubMed

    Pickett, Kate E; Wilkinson, Richard G

    2015-03-01

    There is a very large literature examining income inequality in relation to health. Early reviews came to different interpretations of the evidence, though a large majority of studies reported that health tended to be worse in more unequal societies. More recent studies, not included in those reviews, provide substantial new evidence. Our purpose in this paper is to assess whether or not wider income differences play a causal role leading to worse health. We conducted a literature review within an epidemiological causal framework and inferred the likelihood of a causal relationship between income inequality and health (including violence) by considering the evidence as a whole. The body of evidence strongly suggests that income inequality affects population health and wellbeing. The major causal criteria of temporality, biological plausibility, consistency and lack of alternative explanations are well supported. Of the small minority of studies which find no association, most can be explained by income inequality being measured at an inappropriate scale, the inclusion of mediating variables as controls, the use of subjective rather than objective measures of health, or follow up periods which are too short. The evidence that large income differences have damaging health and social consequences is strong and in most countries inequality is increasing. Narrowing the gap will improve the health and wellbeing of populations.

  11. The metagenomic approach and causality in virology.

    PubMed

    Castrignano, Silvana Beres; Nagasse-Sugahara, Teresa Keico

    2015-01-01

    Nowadays, the metagenomic approach has been a very important tool in the discovery of new viruses in environmental and biological samples. Here we discuss how these discoveries may help to elucidate the etiology of diseases and the criteria necessary to establish a causal association between a virus and a disease.

  12. Introducing Mechanics by Tapping Core Causal Knowledge

    ERIC Educational Resources Information Center

    Klaassen, Kees; Westra, Axel; Emmett, Katrina; Eijkelhof, Harrie; Lijnse, Piet

    2008-01-01

    This article concerns an outline of an introductory mechanics course. It is based on the argument that various uses of the concept of force (e.g. from Kepler, Newton and everyday life) share an explanatory strategy based on core causal knowledge. The strategy consists of (a) the idea that a force causes a deviation from how an object would move of…

  13. Causality and the Levels of Selection.

    PubMed

    Krupp, D B

    2016-04-01

    When is it sensible to say that group selection has shaped organismal design? This question has prompted many replies but few credible solutions. New work that exposes the causal relationships between phenotypes and fitness may finally settle the matter - and a few other things besides.

  14. The metagenomic approach and causality in virology

    PubMed Central

    Castrignano, Silvana Beres; Nagasse-Sugahara, Teresa Keico

    2015-01-01

    Nowadays, the metagenomic approach has been a very important tool in the discovery of new viruses in environmental and biological samples. Here we discuss how these discoveries may help to elucidate the etiology of diseases and the criteria necessary to establish a causal association between a virus and a disease. PMID:25902566

  15. Causal and Teleological Explanations in Biology

    ERIC Educational Resources Information Center

    Yip, Cheng-Wai

    2009-01-01

    A causal explanation in biology focuses on the mechanism by which a biological process is brought about, whereas a teleological explanation considers the end result, in the context of the survival of the organism, as a reason for certain biological processes or structures. There is a tendency among students to offer a teleological explanation…

  16. Causal Poisson bracket via deformation quantization

    NASA Astrophysics Data System (ADS)

    Berra-Montiel, Jasel; Molgado, Alberto; Palacios-García, César D.

    2016-06-01

    Starting with the well-defined product of quantum fields at two spacetime points, we explore an associated Poisson structure for classical field theories within the deformation quantization formalism. We realize that the induced star-product is naturally related to the standard Moyal product through an appropriate causal Green’s functions connecting points in the space of classical solutions to the equations of motion. Our results resemble the Peierls-DeWitt bracket that has been analyzed in the multisymplectic context. Once our star-product is defined, we are able to apply the Wigner-Weyl map in order to introduce a generalized version of Wick’s theorem. Finally, we include some examples to explicitly test our method: the real scalar field, the bosonic string and a physically motivated nonlinear particle model. For the field theoretic models, we have encountered causal generalizations of the creation/annihilation relations, and also a causal generalization of the Virasoro algebra for the bosonic string. For the nonlinear particle case, we use the approximate solution in terms of the Green’s function, in order to construct a well-behaved causal bracket.

  17. A study of carburetor/induction system icing in general aviation accidents

    NASA Technical Reports Server (NTRS)

    Obermayer, R. W.; Roe, W. T.

    1975-01-01

    An assessment of the frequency and severity of carburetor/induction icing in general-aviation accidents was performed. The available literature and accident data from the National Transportation Safety Board were collected. A computer analysis of the accident data was performed. Between 65 and 90 accidents each year involve carburetor/induction system icing as a probable cause/factor. Under conditions conducive to carburetor/induction icing, between 50 and 70 percent of engine malfunction/failure accidents (exclusive of those due to fuel exhaustion) are due to carburetor/induction system icing. Since the evidence of such icing may not remain long after an accident, it is probable that the frequency of occurrence of such accidents is underestimated; therefore, some extrapolation of the data was conducted. The problem of carburetor/induction system icing is particularly acute for pilots with less than 1000 hours of total flying time. The severity of such accidents is about the same as any accident resulting from a forced landing or precautionary landing. About 144 persons, on the average, are exposed to death and injury each year in accidents involving carburetor/induction icing as a probable cause/factor.

  18. A review of criticality accidents

    SciTech Connect

    Stratton, W R; Smith, D R

    1989-03-01

    Criticality accidents and the characteristics of prompt power excursions are discussed. Forty-one accidental power transients are reviewed. In each case where available, enough detail is given to help visualize the physical situation, the cause or causes of the accident, the history and characteristics of the transient, the energy release, and the consequences, if any, to personnel and property. Excursions associated with large power reactors are not included in this study, except that some information on the major accident at the Chernobyl reactor in April 1986 is provided in the Appendix. 67 refs., 21 figs., 2 tabs.

  19. [Prevention of bicycle accidents].

    PubMed

    Zwipp, H; Barthel, P; Bönninger, J; Bürkle, H; Hagemeister, C; Hannawald, L; Huhn, R; Kühn, M; Liers, H; Maier, R; Otte, D; Prokop, G; Seeck, A; Sturm, J; Unger, T

    2015-04-01

    For a very precise analysis of all injured bicyclists in Germany it would be important to have definitions for "severely injured", "seriously injured" and "critically injured". By this, e.g., two-thirds of surgically treated bicyclists who are not registered by the police could become available for a general analysis. Elderly bicyclists (> 60 years) are a minority (10 %) but represent a majority (50 %) of all fatalities. They profit most by wearing a helmet and would be less injured by using special bicycle bags, switching on their hearing aids and following all traffic rules. E-bikes are used more and more (145 % more in 2012 vs. 2011) with 600,000 at the end of 2011 and are increasingly involved in accidents but still have a lack of legislation. So even for pedelecs 45 with 500 W and a possible speed of 45 km/h there is still no legislative demand for the use of a protecting helmet. 96 % of all injured cyclists in Germany had more than 0.5 ‰ alcohol in their blood, 86 % more than 1.1 ‰ and 59 % more than 1.7 ‰. Fatalities are seen in 24.2 % of cases without any collision partner. Therefore the ADFC calls for a limit of 1.1 ‰. Some virtual studies conclude that integrated sensors in bicycle helmets which would interact with sensors in cars could prevent collisions or reduce the severity of injury by stopping the cars automatically. Integrated sensors in cars with opening angles of 180° enable about 93 % of all bicyclists to be detected leading to a high rate of injury avoidance and/or mitigation. Hanging lamps reduce with 35 % significantly bicycle accidents for children, traffic education for children and special trainings for elderly bicyclists are also recommended as prevention tools. As long as helmet use for bicyclists in Germany rates only 9 % on average and legislative orders for using a helmet will not be in force in the near future, coming up campaigns seem to be necessary to be promoted by the Deutscher

  20. [Prevention of bicycle accidents].

    PubMed

    Zwipp, H; Barthel, P; Bönninger, J; Bürkle, H; Hagemeister, C; Hannawald, L; Huhn, R; Kühn, M; Liers, H; Maier, R; Otte, D; Prokop, G; Seeck, A; Sturm, J; Unger, T

    2015-04-01

    For a very precise analysis of all injured bicyclists in Germany it would be important to have definitions for "severely injured", "seriously injured" and "critically injured". By this, e.g., two-thirds of surgically treated bicyclists who are not registered by the police could become available for a general analysis. Elderly bicyclists (> 60 years) are a minority (10 %) but represent a majority (50 %) of all fatalities. They profit most by wearing a helmet and would be less injured by using special bicycle bags, switching on their hearing aids and following all traffic rules. E-bikes are used more and more (145 % more in 2012 vs. 2011) with 600,000 at the end of 2011 and are increasingly involved in accidents but still have a lack of legislation. So even for pedelecs 45 with 500 W and a possible speed of 45 km/h there is still no legislative demand for the use of a protecting helmet. 96 % of all injured cyclists in Germany had more than 0.5 ‰ alcohol in their blood, 86 % more than 1.1 ‰ and 59 % more than 1.7 ‰. Fatalities are seen in 24.2 % of cases without any collision partner. Therefore the ADFC calls for a limit of 1.1 ‰. Some virtual studies conclude that integrated sensors in bicycle helmets which would interact with sensors in cars could prevent collisions or reduce the severity of injury by stopping the cars automatically. Integrated sensors in cars with opening angles of 180° enable about 93 % of all bicyclists to be detected leading to a high rate of injury avoidance and/or mitigation. Hanging lamps reduce with 35 % significantly bicycle accidents for children, traffic education for children and special trainings for elderly bicyclists are also recommended as prevention tools. As long as helmet use for bicyclists in Germany rates only 9 % on average and legislative orders for using a helmet will not be in force in the near future, coming up campaigns seem to be necessary to be promoted by the Deutscher