Sample records for choice knapsack problem

  1. A hybrid heuristic for the multiple choice multidimensional knapsack problem

    NASA Astrophysics Data System (ADS)

    Mansi, Raïd; Alves, Cláudio; Valério de Carvalho, J. M.; Hanafi, Saïd

    2013-08-01

    In this article, a new solution approach for the multiple choice multidimensional knapsack problem is described. The problem is a variant of the multidimensional knapsack problem where items are divided into classes, and exactly one item per class has to be chosen. Both problems are NP-hard. However, the multiple choice multidimensional knapsack problem appears to be more difficult to solve in part because of its choice constraints. Many real applications lead to very large scale multiple choice multidimensional knapsack problems that can hardly be addressed using exact algorithms. A new hybrid heuristic is proposed that embeds several new procedures for this problem. The approach is based on the resolution of linear programming relaxations of the problem and reduced problems that are obtained by fixing some variables of the problem. The solutions of these problems are used to update the global lower and upper bounds for the optimal solution value. A new strategy for defining the reduced problems is explored, together with a new family of cuts and a reformulation procedure that is used at each iteration to improve the performance of the heuristic. An extensive set of computational experiments is reported for benchmark instances from the literature and for a large set of hard instances generated randomly. The results show that the approach outperforms other state-of-the-art methods described so far, providing the best known solution for a significant number of benchmark instances.

  2. Multiple Choice Knapsack Problem: example of planning choice in transportation.

    PubMed

    Zhong, Tao; Young, Rhonda

    2010-05-01

    Transportation programming, a process of selecting projects for funding given budget and other constraints, is becoming more complex as a result of new federal laws, local planning regulations, and increased public involvement. This article describes the use of an integer programming tool, Multiple Choice Knapsack Problem (MCKP), to provide optimal solutions to transportation programming problems in cases where alternative versions of projects are under consideration. In this paper, optimization methods for use in the transportation programming process are compared and then the process of building and solving the optimization problems is discussed. The concepts about the use of MCKP are presented and a real-world transportation programming example at various budget levels is provided. This article illustrates how the use of MCKP addresses the modern complexities and provides timely solutions in transportation programming practice. While the article uses transportation programming as a case study, MCKP can be useful in other fields where a similar decision among a subset of the alternatives is required. Copyright 2009 Elsevier Ltd. All rights reserved.

  3. A set partitioning reformulation for the multiple-choice multidimensional knapsack problem

    NASA Astrophysics Data System (ADS)

    Voß, Stefan; Lalla-Ruiz, Eduardo

    2016-05-01

    The Multiple-choice Multidimensional Knapsack Problem (MMKP) is a well-known ?-hard combinatorial optimization problem that has received a lot of attention from the research community as it can be easily translated to several real-world problems arising in areas such as allocating resources, reliability engineering, cognitive radio networks, cloud computing, etc. In this regard, an exact model that is able to provide high-quality feasible solutions for solving it or being partially included in algorithmic schemes is desirable. The MMKP basically consists of finding a subset of objects that maximizes the total profit while observing some capacity restrictions. In this article a reformulation of the MMKP as a set partitioning problem is proposed to allow for new insights into modelling the MMKP. The computational experimentation provides new insights into the problem itself and shows that the new model is able to improve on the best of the known results for some of the most common benchmark instances.

  4. A Novel Harmony Search Algorithm Based on Teaching-Learning Strategies for 0-1 Knapsack Problems

    PubMed Central

    Tuo, Shouheng; Yong, Longquan; Deng, Fang'an

    2014-01-01

    To enhance the performance of harmony search (HS) algorithm on solving the discrete optimization problems, this paper proposes a novel harmony search algorithm based on teaching-learning (HSTL) strategies to solve 0-1 knapsack problems. In the HSTL algorithm, firstly, a method is presented to adjust dimension dynamically for selected harmony vector in optimization procedure. In addition, four strategies (harmony memory consideration, teaching-learning strategy, local pitch adjusting, and random mutation) are employed to improve the performance of HS algorithm. Another improvement in HSTL method is that the dynamic strategies are adopted to change the parameters, which maintains the proper balance effectively between global exploration power and local exploitation power. Finally, simulation experiments with 13 knapsack problems show that the HSTL algorithm can be an efficient alternative for solving 0-1 knapsack problems. PMID:24574905

  5. A novel harmony search algorithm based on teaching-learning strategies for 0-1 knapsack problems.

    PubMed

    Tuo, Shouheng; Yong, Longquan; Deng, Fang'an

    2014-01-01

    To enhance the performance of harmony search (HS) algorithm on solving the discrete optimization problems, this paper proposes a novel harmony search algorithm based on teaching-learning (HSTL) strategies to solve 0-1 knapsack problems. In the HSTL algorithm, firstly, a method is presented to adjust dimension dynamically for selected harmony vector in optimization procedure. In addition, four strategies (harmony memory consideration, teaching-learning strategy, local pitch adjusting, and random mutation) are employed to improve the performance of HS algorithm. Another improvement in HSTL method is that the dynamic strategies are adopted to change the parameters, which maintains the proper balance effectively between global exploration power and local exploitation power. Finally, simulation experiments with 13 knapsack problems show that the HSTL algorithm can be an efficient alternative for solving 0-1 knapsack problems.

  6. Genetic programming over context-free languages with linear constraints for the knapsack problem: first results.

    PubMed

    Bruhn, Peter; Geyer-Schulz, Andreas

    2002-01-01

    In this paper, we introduce genetic programming over context-free languages with linear constraints for combinatorial optimization, apply this method to several variants of the multidimensional knapsack problem, and discuss its performance relative to Michalewicz's genetic algorithm with penalty functions. With respect to Michalewicz's approach, we demonstrate that genetic programming over context-free languages with linear constraints improves convergence. A final result is that genetic programming over context-free languages with linear constraints is ideally suited to modeling complementarities between items in a knapsack problem: The more complementarities in the problem, the stronger the performance in comparison to its competitors.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brickell, E.F.; Simmons, G.J.

    In the period since 1976, when Diffie and Hellman published the first discussion of two-key cryptography to appear in the open literature, only a handful of two-key cryptoalgorithms have been proposed - two of which are based on the knapsack problem. Consequently there was enormous interest when Shamir announced in early 1982 a cryptanalytic technique that could break many Merkle-Hellman knapsacks. In a rapid sequence of developments, Simmons and Brickell, Adleman, and Lagarias all announced other attacks on knapsack-based cryptosystems that were either computationally much more efficient or else directed at other knapsack schemes such as the Graham-Shamir or iteratedmore » systems. This paper analyzes the common features of knapsack-based cryptosystems and presents all of the cryptanalytic attacks made in 1982 from a unified viewpoint.« less

  8. On the Hardness of Subset Sum Problem from Different Intervals

    NASA Astrophysics Data System (ADS)

    Kogure, Jun; Kunihiro, Noboru; Yamamoto, Hirosuke

    The subset sum problem, which is often called as the knapsack problem, is known as an NP-hard problem, and there are several cryptosystems based on the problem. Assuming an oracle for shortest vector problem of lattice, the low-density attack algorithm by Lagarias and Odlyzko and its variants solve the subset sum problem efficiently, when the “density” of the given problem is smaller than some threshold. When we define the density in the context of knapsack-type cryptosystems, weights are usually assumed to be chosen uniformly at random from the same interval. In this paper, we focus on general subset sum problems, where this assumption may not hold. We assume that weights are chosen from different intervals, and make analysis of the effect on the success probability of above algorithms both theoretically and experimentally. Possible application of our result in the context of knapsack cryptosystems is the security analysis when we reduce the data size of public keys.

  9. A Case Study of Controlling Crossover in a Selection Hyper-heuristic Framework Using the Multidimensional Knapsack Problem.

    PubMed

    Drake, John H; Özcan, Ender; Burke, Edmund K

    2016-01-01

    Hyper-heuristics are high-level methodologies for solving complex problems that operate on a search space of heuristics. In a selection hyper-heuristic framework, a heuristic is chosen from an existing set of low-level heuristics and applied to the current solution to produce a new solution at each point in the search. The use of crossover low-level heuristics is possible in an increasing number of general-purpose hyper-heuristic tools such as HyFlex and Hyperion. However, little work has been undertaken to assess how best to utilise it. Since a single-point search hyper-heuristic operates on a single candidate solution, and two candidate solutions are required for crossover, a mechanism is required to control the choice of the other solution. The frameworks we propose maintain a list of potential solutions for use in crossover. We investigate the use of such lists at two conceptual levels. First, crossover is controlled at the hyper-heuristic level where no problem-specific information is required. Second, it is controlled at the problem domain level where problem-specific information is used to produce good-quality solutions to use in crossover. A number of selection hyper-heuristics are compared using these frameworks over three benchmark libraries with varying properties for an NP-hard optimisation problem: the multidimensional 0-1 knapsack problem. It is shown that allowing crossover to be managed at the domain level outperforms managing crossover at the hyper-heuristic level in this problem domain.

  10. Approximating the 0-1 Multiple Knapsack Problem with Agent Decomposition and Market Negotiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smolinski, B.

    The 0-1 multiple knapsack problem appears in many domains from financial portfolio management to cargo ship stowing. Methods for solving it range from approximate algorithms, such as greedy algorithms, to exact algorithms, such as branch and bound. Approximate algorithms have no bounds on how poorly they perform and exact algorithms can suffer from exponential time and space complexities with large data sets. This paper introduces a market model based on agent decomposition and market auctions for approximating the 0-1 multiple knapsack problem, and an algorithm that implements the model (M(x)). M(x) traverses the solution space rather than getting caught inmore » a local maximum, overcoming an inherent problem of many greedy algorithms. The use of agents ensures that infeasible solutions are not considered while traversing the solution space and that traversal of the solution space is not just random, but is also directed. M(x) is compared to a bound and bound algorithm (BB) and a simple greedy algorithm with a random shuffle (G(x)). The results suggest that M(x) is a good algorithm for approximating the 0-1 Multiple Knapsack problem. M(x) almost always found solutions that were close to optimal in a fraction of the time it took BB to run and with much less memory on large test data sets. M(x) usually performed better than G(x) on hard problems with correlated data.« less

  11. The Subset Sum game.

    PubMed

    Darmann, Andreas; Nicosia, Gaia; Pferschy, Ulrich; Schauer, Joachim

    2014-03-16

    In this work we address a game theoretic variant of the Subset Sum problem, in which two decision makers (agents/players) compete for the usage of a common resource represented by a knapsack capacity. Each agent owns a set of integer weighted items and wants to maximize the total weight of its own items included in the knapsack. The solution is built as follows: Each agent, in turn, selects one of its items (not previously selected) and includes it in the knapsack if there is enough capacity. The process ends when the remaining capacity is too small for including any item left. We look at the problem from a single agent point of view and show that finding an optimal sequence of items to select is an [Formula: see text]-hard problem. Therefore we propose two natural heuristic strategies and analyze their worst-case performance when (1) the opponent is able to play optimally and (2) the opponent adopts a greedy strategy. From a centralized perspective we observe that some known results on the approximation of the classical Subset Sum can be effectively adapted to the multi-agent version of the problem.

  12. The Subset Sum game☆

    PubMed Central

    Darmann, Andreas; Nicosia, Gaia; Pferschy, Ulrich; Schauer, Joachim

    2014-01-01

    In this work we address a game theoretic variant of the Subset Sum problem, in which two decision makers (agents/players) compete for the usage of a common resource represented by a knapsack capacity. Each agent owns a set of integer weighted items and wants to maximize the total weight of its own items included in the knapsack. The solution is built as follows: Each agent, in turn, selects one of its items (not previously selected) and includes it in the knapsack if there is enough capacity. The process ends when the remaining capacity is too small for including any item left. We look at the problem from a single agent point of view and show that finding an optimal sequence of items to select is an NP-hard problem. Therefore we propose two natural heuristic strategies and analyze their worst-case performance when (1) the opponent is able to play optimally and (2) the opponent adopts a greedy strategy. From a centralized perspective we observe that some known results on the approximation of the classical Subset Sum can be effectively adapted to the multi-agent version of the problem. PMID:25844012

  13. The generalized quadratic knapsack problem. A neuronal network approach.

    PubMed

    Talaván, Pedro M; Yáñez, Javier

    2006-05-01

    The solution of an optimization problem through the continuous Hopfield network (CHN) is based on some energy or Lyapunov function, which decreases as the system evolves until a local minimum value is attained. A new energy function is proposed in this paper so that any 0-1 linear constrains programming with quadratic objective function can be solved. This problem, denoted as the generalized quadratic knapsack problem (GQKP), includes as particular cases well-known problems such as the traveling salesman problem (TSP) and the quadratic assignment problem (QAP). This new energy function generalizes those proposed by other authors. Through this energy function, any GQKP can be solved with an appropriate parameter setting procedure, which is detailed in this paper. As a particular case, and in order to test this generalized energy function, some computational experiments solving the traveling salesman problem are also included.

  14. a Genetic Algorithm Based on Sexual Selection for the Multidimensional 0/1 Knapsack Problems

    NASA Astrophysics Data System (ADS)

    Varnamkhasti, Mohammad Jalali; Lee, Lai Soon

    In this study, a new technique is presented for choosing mate chromosomes during sexual selection in a genetic algorithm. The population is divided into groups of males and females. During the sexual selection, the female chromosome is selected by the tournament selection while the male chromosome is selected based on the hamming distance from the selected female chromosome, fitness value or active genes. Computational experiments are conducted on the proposed technique and the results are compared with some selection mechanisms commonly used for solving multidimensional 0/1 knapsack problems published in the literature.

  15. An iterative bidirectional heuristic placement algorithm for solving the two-dimensional knapsack packing problem

    NASA Astrophysics Data System (ADS)

    Shiangjen, Kanokwatt; Chaijaruwanich, Jeerayut; Srisujjalertwaja, Wijak; Unachak, Prakarn; Somhom, Samerkae

    2018-02-01

    This article presents an efficient heuristic placement algorithm, namely, a bidirectional heuristic placement, for solving the two-dimensional rectangular knapsack packing problem. The heuristic demonstrates ways to maximize space utilization by fitting the appropriate rectangle from both sides of the wall of the current residual space layer by layer. The iterative local search along with a shift strategy is developed and applied to the heuristic to balance the exploitation and exploration tasks in the solution space without the tuning of any parameters. The experimental results on many scales of packing problems show that this approach can produce high-quality solutions for most of the benchmark datasets, especially for large-scale problems, within a reasonable duration of computational time.

  16. An Effective Hybrid Cuckoo Search Algorithm with Improved Shuffled Frog Leaping Algorithm for 0-1 Knapsack Problems

    PubMed Central

    Wang, Gai-Ge; Feng, Qingjiang; Zhao, Xiang-Jun

    2014-01-01

    An effective hybrid cuckoo search algorithm (CS) with improved shuffled frog-leaping algorithm (ISFLA) is put forward for solving 0-1 knapsack problem. First of all, with the framework of SFLA, an improved frog-leap operator is designed with the effect of the global optimal information on the frog leaping and information exchange between frog individuals combined with genetic mutation with a small probability. Subsequently, in order to improve the convergence speed and enhance the exploitation ability, a novel CS model is proposed with considering the specific advantages of Lévy flights and frog-leap operator. Furthermore, the greedy transform method is used to repair the infeasible solution and optimize the feasible solution. Finally, numerical simulations are carried out on six different types of 0-1 knapsack instances, and the comparative results have shown the effectiveness of the proposed algorithm and its ability to achieve good quality solutions, which outperforms the binary cuckoo search, the binary differential evolution, and the genetic algorithm. PMID:25404940

  17. On local search for bi-objective knapsack problems.

    PubMed

    Liefooghe, Arnaud; Paquete, Luís; Figueira, José Rui

    2013-01-01

    In this article, a local search approach is proposed for three variants of the bi-objective binary knapsack problem, with the aim of maximizing the total profit and minimizing the total weight. First, an experimental study on a given structural property of connectedness of the efficient set is conducted. Based on this property, a local search algorithm is proposed and its performance is compared to exact algorithms in terms of runtime and quality metrics. The experimental results indicate that this simple local search algorithm is able to find a representative set of optimal solutions in most of the cases, and in much less time than exact algorithms.

  18. Dynamic Inertia Weight Binary Bat Algorithm with Neighborhood Search

    PubMed Central

    2017-01-01

    Binary bat algorithm (BBA) is a binary version of the bat algorithm (BA). It has been proven that BBA is competitive compared to other binary heuristic algorithms. Since the update processes of velocity in the algorithm are consistent with BA, in some cases, this algorithm also faces the premature convergence problem. This paper proposes an improved binary bat algorithm (IBBA) to solve this problem. To evaluate the performance of IBBA, standard benchmark functions and zero-one knapsack problems have been employed. The numeric results obtained by benchmark functions experiment prove that the proposed approach greatly outperforms the original BBA and binary particle swarm optimization (BPSO). Compared with several other heuristic algorithms on zero-one knapsack problems, it also verifies that the proposed algorithm is more able to avoid local minima. PMID:28634487

  19. Dynamic Inertia Weight Binary Bat Algorithm with Neighborhood Search.

    PubMed

    Huang, Xingwang; Zeng, Xuewen; Han, Rui

    2017-01-01

    Binary bat algorithm (BBA) is a binary version of the bat algorithm (BA). It has been proven that BBA is competitive compared to other binary heuristic algorithms. Since the update processes of velocity in the algorithm are consistent with BA, in some cases, this algorithm also faces the premature convergence problem. This paper proposes an improved binary bat algorithm (IBBA) to solve this problem. To evaluate the performance of IBBA, standard benchmark functions and zero-one knapsack problems have been employed. The numeric results obtained by benchmark functions experiment prove that the proposed approach greatly outperforms the original BBA and binary particle swarm optimization (BPSO). Compared with several other heuristic algorithms on zero-one knapsack problems, it also verifies that the proposed algorithm is more able to avoid local minima.

  20. An automated system for reduction of the firm's employees under maximal overall efficiency

    NASA Astrophysics Data System (ADS)

    Yonchev, Yoncho; Nikolov, Simeon; Baeva, Silvia

    2012-11-01

    Achieving maximal overall efficiency is a priority in all companies. This problem is formulated as a knap-sack problem and afterwards as a linear assignment problem. An automated system is created for solving of this problem.

  1. Parallelization of combinatorial search when solving knapsack optimization problem on computing systems based on multicore processors

    NASA Astrophysics Data System (ADS)

    Rahman, P. A.

    2018-05-01

    This scientific paper deals with the model of the knapsack optimization problem and method of its solving based on directed combinatorial search in the boolean space. The offered by the author specialized mathematical model of decomposition of the search-zone to the separate search-spheres and the algorithm of distribution of the search-spheres to the different cores of the multi-core processor are also discussed. The paper also provides an example of decomposition of the search-zone to the several search-spheres and distribution of the search-spheres to the different cores of the quad-core processor. Finally, an offered by the author formula for estimation of the theoretical maximum of the computational acceleration, which can be achieved due to the parallelization of the search-zone to the search-spheres on the unlimited number of the processor cores, is also given.

  2. Cooperative parallel adaptive neighbourhood search for the disjunctively constrained knapsack problem

    NASA Astrophysics Data System (ADS)

    Quan, Zhe; Wu, Lei

    2017-09-01

    This article investigates the use of parallel computing for solving the disjunctively constrained knapsack problem. The proposed parallel computing model can be viewed as a cooperative algorithm based on a multi-neighbourhood search. The cooperation system is composed of a team manager and a crowd of team members. The team members aim at applying their own search strategies to explore the solution space. The team manager collects the solutions from the members and shares the best one with them. The performance of the proposed method is evaluated on a group of benchmark data sets. The results obtained are compared to those reached by the best methods from the literature. The results show that the proposed method is able to provide the best solutions in most cases. In order to highlight the robustness of the proposed parallel computing model, a new set of large-scale instances is introduced. Encouraging results have been obtained.

  3. Comparison of a new air-assisted sprayer and two conventional sprayers in terms of deposition, loss to the soil and residue of azoxystrobin and tebuconazole applied to sunlit greenhouse tomato and field cucumber.

    PubMed

    Li, Yanjie; Li, Yifan; Pan, Xiang; Li, Qing X; Chen, Ronghua; Li, Xuesheng; Pan, Canping; Song, Jianli

    2018-02-01

    Plant protection products (PPPs) are applied in China and many other developing countries with knapsack sprayers at high volumes with coarse spray quality, resulting in a high percentage of pesticide losses. In this study, a new air-assisted electric knapsack sprayer and two conventional knapsack sprayers were evaluated in terms of pesticide deposition, residues and loss into the soil. Artificial targets fixed to the upper side and underside of the leaf surface in six zones (at two depths and three heights) were used to collect the deposition, which were analyzed by liquid chromatography triple-quadrupole mass spectrometry. The air-assisted electric knapsack sprayer produced more deposition and better penetrability and uniformity than the two traditional spraying methods. In particular, the air-assisted electric knapsack sprayer reduced pesticide losses to the soil by roughly 37% to 75% and deposited 1.18 and 1.24 times more pesticide than the manual air-pressure and battery-powered knapsack sprayers, respectively. The residues of azoxystrobin and tebuconazole in tomato and cucumber were below the maximum residue limits (MRLs). In general, use of the the air-assisted electric knapsack sprayer in tomato and cucumber crops could improve the effectiveness of PPPs, reduce the risk of contamination and protect food safety. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  4. An Improved Hybrid Encoding Cuckoo Search Algorithm for 0-1 Knapsack Problems

    PubMed Central

    Feng, Yanhong; Jia, Ke; He, Yichao

    2014-01-01

    Cuckoo search (CS) is a new robust swarm intelligence method that is based on the brood parasitism of some cuckoo species. In this paper, an improved hybrid encoding cuckoo search algorithm (ICS) with greedy strategy is put forward for solving 0-1 knapsack problems. First of all, for solving binary optimization problem with ICS, based on the idea of individual hybrid encoding, the cuckoo search over a continuous space is transformed into the synchronous evolution search over discrete space. Subsequently, the concept of confidence interval (CI) is introduced; hence, the new position updating is designed and genetic mutation with a small probability is introduced. The former enables the population to move towards the global best solution rapidly in every generation, and the latter can effectively prevent the ICS from trapping into the local optimum. Furthermore, the greedy transform method is used to repair the infeasible solution and optimize the feasible solution. Experiments with a large number of KP instances show the effectiveness of the proposed algorithm and its ability to achieve good quality solutions. PMID:24527026

  5. A tight upper bound for quadratic knapsack problems in grid-based wind farm layout optimization

    NASA Astrophysics Data System (ADS)

    Quan, Ning; Kim, Harrison M.

    2018-03-01

    The 0-1 quadratic knapsack problem (QKP) in wind farm layout optimization models possible turbine locations as nodes, and power loss due to wake effects between pairs of turbines as edges in a complete graph. The goal is to select up to a certain number of turbine locations such that the sum of selected node and edge coefficients is maximized. Finding the optimal solution to the QKP is difficult in general, but it is possible to obtain a tight upper bound on the QKP's optimal value which facilitates the use of heuristics to solve QKPs by giving a good estimate of the optimality gap of any feasible solution. This article applies an upper bound method that is especially well-suited to QKPs in wind farm layout optimization due to certain features of the formulation that reduce the computational complexity of calculating the upper bound. The usefulness of the upper bound was demonstrated by assessing the performance of the greedy algorithm for solving QKPs in wind farm layout optimization. The results show that the greedy algorithm produces good solutions within 4% of the optimal value for small to medium sized problems considered in this article.

  6. Learning dominance relations in combinatorial search problems

    NASA Technical Reports Server (NTRS)

    Yu, Chee-Fen; Wah, Benjamin W.

    1988-01-01

    Dominance relations commonly are used to prune unnecessary nodes in search graphs, but they are problem-dependent and cannot be derived by a general procedure. The authors identify machine learning of dominance relations and the applicable learning mechanisms. A study of learning dominance relations using learning by experimentation is described. This system has been able to learn dominance relations for the 0/1-knapsack problem, an inventory problem, the reliability-by-replication problem, the two-machine flow shop problem, a number of single-machine scheduling problems, and a two-machine scheduling problem. It is considered that the same methodology can be extended to learn dominance relations in general.

  7. Learning automata-based solutions to the nonlinear fractional knapsack problem with applications to optimal resource allocation.

    PubMed

    Granmo, Ole-Christoffer; Oommen, B John; Myrer, Svein Arild; Olsen, Morten Goodwin

    2007-02-01

    This paper considers the nonlinear fractional knapsack problem and demonstrates how its solution can be effectively applied to two resource allocation problems dealing with the World Wide Web. The novel solution involves a "team" of deterministic learning automata (LA). The first real-life problem relates to resource allocation in web monitoring so as to "optimize" information discovery when the polling capacity is constrained. The disadvantages of the currently reported solutions are explained in this paper. The second problem concerns allocating limited sampling resources in a "real-time" manner with the purpose of estimating multiple binomial proportions. This is the scenario encountered when the user has to evaluate multiple web sites by accessing a limited number of web pages, and the proportions of interest are the fraction of each web site that is successfully validated by an HTML validator. Using the general LA paradigm to tackle both of the real-life problems, the proposed scheme improves a current solution in an online manner through a series of informed guesses that move toward the optimal solution. At the heart of the scheme, a team of deterministic LA performs a controlled random walk on a discretized solution space. Comprehensive experimental results demonstrate that the discretization resolution determines the precision of the scheme, and that for a given precision, the current solution (to both problems) is consistently improved until a nearly optimal solution is found--even for switching environments. Thus, the scheme, while being novel to the entire field of LA, also efficiently handles a class of resource allocation problems previously not addressed in the literature.

  8. Development and Mining of a Volatile Organic Compound Database

    PubMed Central

    Abdullah, Azian Azamimi; Ono, Naoaki; Sugiura, Tadao; Morita, Aki Hirai; Katsuragi, Tetsuo; Muto, Ai; Nishioka, Takaaki; Kanaya, Shigehiko

    2015-01-01

    Volatile organic compounds (VOCs) are small molecules that exhibit high vapor pressure under ambient conditions and have low boiling points. Although VOCs contribute only a small proportion of the total metabolites produced by living organisms, they play an important role in chemical ecology specifically in the biological interactions between organisms and ecosystems. VOCs are also important in the health care field as they are presently used as a biomarker to detect various human diseases. Information on VOCs is scattered in the literature until now; however, there is still no available database describing VOCs and their biological activities. To attain this purpose, we have developed KNApSAcK Metabolite Ecology Database, which contains the information on the relationships between VOCs and their emitting organisms. The KNApSAcK Metabolite Ecology is also linked with the KNApSAcK Core and KNApSAcK Metabolite Activity Database to provide further information on the metabolites and their biological activities. The VOC database can be accessed online. PMID:26495281

  9. Optimal reconfiguration strategy for a degradable multimodule computing system

    NASA Technical Reports Server (NTRS)

    Lee, Yann-Hang; Shin, Kang G.

    1987-01-01

    The present quantitative approach to the problem of reconfiguring a degradable multimode system assigns some modules to computation and arranges others for reliability. By using expected total reward as the optimal criterion, there emerges an active reconfiguration strategy based not only on the occurrence of failure but the progression of the given mission. This reconfiguration strategy requires specification of the times at which the system should undergo reconfiguration, and the configurations to which the system should change. The optimal reconfiguration problem is converted to integer nonlinear knapsack and fractional programming problems.

  10. Solving a Class of Stochastic Mixed-Integer Programs With Branch and Price

    DTIC Science & Technology

    2006-01-01

    a two-dimensional knapsack problem, but for a given m, the objective value gi does not depend on the variance index v. This will be used in a final...optimization. Journal of Multicriteria Decision Analysis 11, 139–150 (2002) 29. Ford, L.R., Fulkerson, D.R.: A suggested computation for the maximal...for solution by a branch-and-price algorithm (B&P). We then survey a number of examples, and use a stochastic facility-location problem (SFLP) for a

  11. Unpacking Teachers' Invisible Knapsacks: Social Identity and Privilege in Higher Education

    ERIC Educational Resources Information Center

    Barnett, Pamela E.

    2013-01-01

    Peggy McIntosh (1988) famously unpacked what she called an "invisible knapsack" of privileges socially conferred upon whites, men, and heterosexuals (1988). She argued that not only are women and minorities at a disadvantage, but those with social power enjoy benefits that are both unearned and unjustified. We often accept those…

  12. Automating the packing heuristic design process with genetic programming.

    PubMed

    Burke, Edmund K; Hyde, Matthew R; Kendall, Graham; Woodward, John

    2012-01-01

    The literature shows that one-, two-, and three-dimensional bin packing and knapsack packing are difficult problems in operational research. Many techniques, including exact, heuristic, and metaheuristic approaches, have been investigated to solve these problems and it is often not clear which method to use when presented with a new instance. This paper presents an approach which is motivated by the goal of building computer systems which can design heuristic methods. The overall aim is to explore the possibilities for automating the heuristic design process. We present a genetic programming system to automatically generate a good quality heuristic for each instance. It is not necessary to change the methodology depending on the problem type (one-, two-, or three-dimensional knapsack and bin packing problems), and it therefore has a level of generality unmatched by other systems in the literature. We carry out an extensive suite of experiments and compare with the best human designed heuristics in the literature. Note that our heuristic design methodology uses the same parameters for all the experiments. The contribution of this paper is to present a more general packing methodology than those currently available, and to show that, by using this methodology, it is possible for a computer system to design heuristics which are competitive with the human designed heuristics from the literature. This represents the first packing algorithm in the literature able to claim human competitive results in such a wide variety of packing domains.

  13. An Empirical Comparison of Seven Iterative and Evolutionary Function Optimization Heuristics

    NASA Technical Reports Server (NTRS)

    Baluja, Shumeet

    1995-01-01

    This report is a repository of the results obtained from a large scale empirical comparison of seven iterative and evolution-based optimization heuristics. Twenty-seven static optimization problems, spanning six sets of problem classes which are commonly explored in genetic algorithm literature, are examined. The problem sets include job-shop scheduling, traveling salesman, knapsack, binpacking, neural network weight optimization, and standard numerical optimization. The search spaces in these problems range from 2368 to 22040. The results indicate that using genetic algorithms for the optimization of static functions does not yield a benefit, in terms of the final answer obtained, over simpler optimization heuristics. Descriptions of the algorithms tested and the encodings of the problems are described in detail for reproducibility.

  14. The cost-constrained traveling salesman problem

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sokkappa, P.R.

    1990-10-01

    The Cost-Constrained Traveling Salesman Problem (CCTSP) is a variant of the well-known Traveling Salesman Problem (TSP). In the TSP, the goal is to find a tour of a given set of cities such that the total cost of the tour is minimized. In the CCTSP, each city is given a value, and a fixed cost-constraint is specified. The objective is to find a subtour of the cities that achieves maximum value without exceeding the cost-constraint. Thus, unlike the TSP, the CCTSP requires both selection and sequencing. As a consequence, most results for the TSP cannot be extended to the CCTSP.more » We show that the CCTSP is NP-hard and that no K-approximation algorithm or fully polynomial approximation scheme exists, unless P = NP. We also show that several special cases are polynomially solvable. Algorithms for the CCTSP, which outperform previous methods, are developed in three areas: upper bounding methods, exact algorithms, and heuristics. We found that a bounding strategy based on the knapsack problem performs better, both in speed and in the quality of the bounds, than methods based on the assignment problem. Likewise, we found that a branch-and-bound approach using the knapsack bound was superior to a method based on a common branch-and-bound method for the TSP. In our study of heuristic algorithms, we found that, when selecting modes for inclusion in the subtour, it is important to consider the neighborhood'' of the nodes. A node with low value that brings the subtour near many other nodes may be more desirable than an isolated node of high value. We found two types of repetition to be desirable: repetitions based on randomization in the subtour buildings process, and repetitions encouraging the inclusion of different subsets of the nodes. By varying the number and type of repetitions, we can adjust the computation time required by our method to obtain algorithms that outperform previous methods.« less

  15. Model for the design of distributed data bases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ram, S.

    This research focuses on developing a model to solve the File Allocation Problem (FAP). The model integrates two major design issues, namely Concurrently Control and Data Distribution. The central node locking mechanism is incorporated in developing a nonlinear integer programming model. Two solution algorithms are proposed, one of which was implemented in FORTRAN.V. The allocation of data bases and programs are examined using this heuristic. Several decision rules were also formulated based on the results of the heuristic. A second more comprehensive heuristic was proposed, based on the knapsack problem. The development and implementation of this algorithm has been leftmore » as a topic for future research.« less

  16. Fidelity-Based Ant Colony Algorithm with Q-learning of Quantum System

    NASA Astrophysics Data System (ADS)

    Liao, Qin; Guo, Ying; Tu, Yifeng; Zhang, Hang

    2018-03-01

    Quantum ant colony algorithm (ACA) has potential applications in quantum information processing, such as solutions of traveling salesman problem, zero-one knapsack problem, robot route planning problem, and so on. To shorten the search time of the ACA, we suggest the fidelity-based ant colony algorithm (FACA) for the control of quantum system. Motivated by structure of the Q-learning algorithm, we demonstrate the combination of a FACA with the Q-learning algorithm and suggest the design of a fidelity-based ant colony algorithm with the Q-learning to improve the performance of the FACA in a spin-1/2 quantum system. The numeric simulation results show that the FACA with the Q-learning can efficiently avoid trapping into local optimal policies and increase the speed of convergence process of quantum system.

  17. Fidelity-Based Ant Colony Algorithm with Q-learning of Quantum System

    NASA Astrophysics Data System (ADS)

    Liao, Qin; Guo, Ying; Tu, Yifeng; Zhang, Hang

    2017-12-01

    Quantum ant colony algorithm (ACA) has potential applications in quantum information processing, such as solutions of traveling salesman problem, zero-one knapsack problem, robot route planning problem, and so on. To shorten the search time of the ACA, we suggest the fidelity-based ant colony algorithm (FACA) for the control of quantum system. Motivated by structure of the Q-learning algorithm, we demonstrate the combination of a FACA with the Q-learning algorithm and suggest the design of a fidelity-based ant colony algorithm with the Q-learning to improve the performance of the FACA in a spin-1/2 quantum system. The numeric simulation results show that the FACA with the Q-learning can efficiently avoid trapping into local optimal policies and increase the speed of convergence process of quantum system.

  18. Systematization of the protein sequence diversity in enzymes related to secondary metabolic pathways in plants, in the context of big data biology inspired by the KNApSAcK motorcycle database.

    PubMed

    Ikeda, Shun; Abe, Takashi; Nakamura, Yukiko; Kibinge, Nelson; Hirai Morita, Aki; Nakatani, Atsushi; Ono, Naoaki; Ikemura, Toshimichi; Nakamura, Kensuke; Altaf-Ul-Amin, Md; Kanaya, Shigehiko

    2013-05-01

    Biology is increasingly becoming a data-intensive science with the recent progress of the omics fields, e.g. genomics, transcriptomics, proteomics and metabolomics. The species-metabolite relationship database, KNApSAcK Core, has been widely utilized and cited in metabolomics research, and chronological analysis of that research work has helped to reveal recent trends in metabolomics research. To meet the needs of these trends, the KNApSAcK database has been extended by incorporating a secondary metabolic pathway database called Motorcycle DB. We examined the enzyme sequence diversity related to secondary metabolism by means of batch-learning self-organizing maps (BL-SOMs). Initially, we constructed a map by using a big data matrix consisting of the frequencies of all possible dipeptides in the protein sequence segments of plants and bacteria. The enzyme sequence diversity of the secondary metabolic pathways was examined by identifying clusters of segments associated with certain enzyme groups in the resulting map. The extent of diversity of 15 secondary metabolic enzyme groups is discussed. Data-intensive approaches such as BL-SOM applied to big data matrices are needed for systematizing protein sequences. Handling big data has become an inevitable part of biology.

  19. File text security using Hybrid Cryptosystem with Playfair Cipher Algorithm and Knapsack Naccache-Stern Algorithm

    NASA Astrophysics Data System (ADS)

    Amalia; Budiman, M. A.; Sitepu, R.

    2018-03-01

    Cryptography is one of the best methods to keep the information safe from security attack by unauthorized people. At present, Many studies had been done by previous researchers to generate a more robust cryptographic algorithm to provide high security for data communication. To strengthen data security, one of the methods is hybrid cryptosystem method that combined symmetric and asymmetric algorithm. In this study, we observed a hybrid cryptosystem method contain Modification Playfair Cipher 16x16 algorithm as a symmetric algorithm and Knapsack Naccache-Stern as an asymmetric algorithm. We observe a running time of this hybrid algorithm with some of the various experiments. We tried different amount of characters to be tested which are 10, 100, 1000, 10000 and 100000 characters and we also examined the algorithm with various key’s length which are 10, 20, 30, 40 of key length. The result of our study shows that the processing time for encryption and decryption process each algorithm is linearly proportional, it means the longer messages character then, the more significant times needed to encrypt and decrypt the messages. The encryption running time of Knapsack Naccache-Stern algorithm takes a longer time than its decryption, while the encryption running time of modification Playfair Cipher 16x16 algorithm takes less time than its decryption.

  20. General Quantum Meet-in-the-Middle Search Algorithm Based on Target Solution of Fixed Weight

    NASA Astrophysics Data System (ADS)

    Fu, Xiang-Qun; Bao, Wan-Su; Wang, Xiang; Shi, Jian-Hong

    2016-10-01

    Similar to the classical meet-in-the-middle algorithm, the storage and computation complexity are the key factors that decide the efficiency of the quantum meet-in-the-middle algorithm. Aiming at the target vector of fixed weight, based on the quantum meet-in-the-middle algorithm, the algorithm for searching all n-product vectors with the same weight is presented, whose complexity is better than the exhaustive search algorithm. And the algorithm can reduce the storage complexity of the quantum meet-in-the-middle search algorithm. Then based on the algorithm and the knapsack vector of the Chor-Rivest public-key crypto of fixed weight d, we present a general quantum meet-in-the-middle search algorithm based on the target solution of fixed weight, whose computational complexity is \\sumj = 0d {(O(\\sqrt {Cn - k + 1d - j }) + O(C_kj log C_k^j))} with Σd i =0 Ck i memory cost. And the optimal value of k is given. Compared to the quantum meet-in-the-middle search algorithm for knapsack problem and the quantum algorithm for searching a target solution of fixed weight, the computational complexity of the algorithm is lower. And its storage complexity is smaller than the quantum meet-in-the-middle-algorithm. Supported by the National Basic Research Program of China under Grant No. 2013CB338002 and the National Natural Science Foundation of China under Grant No. 61502526

  1. Solving NP-Hard Problems with Physarum-Based Ant Colony System.

    PubMed

    Liu, Yuxin; Gao, Chao; Zhang, Zili; Lu, Yuxiao; Chen, Shi; Liang, Mingxin; Tao, Li

    2017-01-01

    NP-hard problems exist in many real world applications. Ant colony optimization (ACO) algorithms can provide approximate solutions for those NP-hard problems, but the performance of ACO algorithms is significantly reduced due to premature convergence and weak robustness, etc. With these observations in mind, this paper proposes a Physarum-based pheromone matrix optimization strategy in ant colony system (ACS) for solving NP-hard problems such as traveling salesman problem (TSP) and 0/1 knapsack problem (0/1 KP). In the Physarum-inspired mathematical model, one of the unique characteristics is that critical tubes can be reserved in the process of network evolution. The optimized updating strategy employs the unique feature and accelerates the positive feedback process in ACS, which contributes to the quick convergence of the optimal solution. Some experiments were conducted using both benchmark and real datasets. The experimental results show that the optimized ACS outperforms other meta-heuristic algorithms in accuracy and robustness for solving TSPs. Meanwhile, the convergence rate and robustness for solving 0/1 KPs are better than those of classical ACS.

  2. Quantification of emissions from knapsack sprayers: 'the weight method

    NASA Astrophysics Data System (ADS)

    Garcia-Santos, Glenda; Binder, Claudia R.

    2010-05-01

    Misuse of pesticides kill or seriously sicken thousands of people every year and poison the natural environment. Investigations of occupational and environmental risk have received considerable interest over the last decades. And yet, lack of staff and analytical equipments as well the costs of chemical analyses make difficult, if not impossible, the control of the pesticide contamination and residues in humans, air, water, and soils in developing countries. To assess emissions of pesticides (transport and deposition) during spray application and the risk for the human health and the environment, tracers can be useful tools. Uranine was used to quantify drift airborne and later deposition on the neighbouring field and clothes of the applicator after spraying with a knapsack sprayer in one of the biggest areas of potato production in Colombia. Keeping the same setup the amount of wet drift was measured by difference in the weight of high absorbent papers used to collect the tracer. Surprisingly this weight method (Weight-HAP) was able to explain 71% of the drift variance measured with the tracer. Therefore the weight method is presented as a suitable rapid low cost screening tool, complementary to toxicological tests, to assess air pollution, occupational and environmental exposure generated by the emissions from knapsack sprayers during pesticide application. This technique might be important in places were there is lack of analytical instruments.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brickell, E.F.; Davis, J.A.; Simmons, G.J.

    A study of the algorithm and the underlying mathematical concepts of A Polynomial Time Algorithm for Breaking Merkle-Hellman Cryptosystems, by Adi Shamir, is presented. Ways of protecting the Merkle-Hellman knapsack from cryptanalysis are given with derivations. (GHT)

  4. An adaptive evolutionary multi-objective approach based on simulated annealing.

    PubMed

    Li, H; Landa-Silva, D

    2011-01-01

    A multi-objective optimization problem can be solved by decomposing it into one or more single objective subproblems in some multi-objective metaheuristic algorithms. Each subproblem corresponds to one weighted aggregation function. For example, MOEA/D is an evolutionary multi-objective optimization (EMO) algorithm that attempts to optimize multiple subproblems simultaneously by evolving a population of solutions. However, the performance of MOEA/D highly depends on the initial setting and diversity of the weight vectors. In this paper, we present an improved version of MOEA/D, called EMOSA, which incorporates an advanced local search technique (simulated annealing) and adapts the search directions (weight vectors) corresponding to various subproblems. In EMOSA, the weight vector of each subproblem is adaptively modified at the lowest temperature in order to diversify the search toward the unexplored parts of the Pareto-optimal front. Our computational results show that EMOSA outperforms six other well established multi-objective metaheuristic algorithms on both the (constrained) multi-objective knapsack problem and the (unconstrained) multi-objective traveling salesman problem. Moreover, the effects of the main algorithmic components and parameter sensitivities on the search performance of EMOSA are experimentally investigated.

  5. [A case-control study on the risk factors of work-related acute pesticide poisoning among farmers from Jiangsu province].

    PubMed

    Tu, Zhi-bin; Cui, Meng-jing; Yao, Hong-yan; Hu, Guo-qing; Xiang, Hui-yun; Stallones, Lorann; Zhang, Xu-jun

    2012-04-01

    To explore the risk factors on cases regarding work-related acute pesticide poisoning among farmers of Jiangsu province. A population-based, 1:2 matched case-control study was carried out, with 121 patients as case-group paired by 242 persons with same gender, district and age less then difference of 3 years, as controls. Cases were the ones who had suffered from work-related acute pesticide poisoning. A unified questionnaire was used. Data base was established by EpiData 3.1, and SPSS 16.0 was used for both data single factor and multi-conditional logistics regression analysis. Results from the single factor logistic regression analysis showed that the related risk factors were: lack of safety guidance, lack of readable labels before praying pesticides, no regression during application, using hand to wipe sweat, using leaking knapsack, body contaminated during application and continuing to work when feeling ill after the contact of pesticides. Results from multi-conditional logistic regression analysis indicated that the lack of safety guidance (OR=2.25, 95%CI: 1.35-3.74), no readable labels before praying pesticides (OR=1.95, 95%CI: 1.19-3.18), wiping the sweat by hand during application (OR=1.97, 95%CI: 1.20-3.24) and using leaking knapsack during application (OR=1.82, 95%CI:1.10-3.01) were risk factors for the occurrence of work-related acute pesticide poisoning. The lack of safety guidance, no readable labels before praying pesticides, wiping the sweat by hand or using leaking knapsack during application were correlated to the occurrence of work-related acute pesticide poisoning.

  6. Making Unseen Privilege Visible in Mathematics Education Research

    ERIC Educational Resources Information Center

    Bartell, Tonya Gau; Johnson, Kate R.

    2013-01-01

    In this essay, the authors begin to "unpack the invisible knapsack" of mathematics education research privilege. They present short statements representing the multiplicity of their respective identities; acknowledging that efforts to understand privilege and oppression are often supported and constrained by identities. The authors then…

  7. Drift from the Use of Hand-Held Knapsack Pesticide Sprayers in Boyacá (Colombian Andes).

    PubMed

    García-Santos, Glenda; Feola, Giuseppe; Nuyttens, David; Diaz, Jaime

    2016-05-25

    Offsite pesticide losses in tropical mountainous regions have been little studied. One example is measuring pesticide drift soil deposition, which can support pesticide risk assessment for surface water, soil, bystanders, and off-target plants and fauna. This is considered a serious gap, given the evidence of pesticide-related poisoning in those regions. Empirical data of drift deposition of a pesticide surrogate, Uranine tracer, within one of the highest potato-producing regions in Colombia, characterized by small plots and mountain orography, is presented. High drift values encountered in this study reflect the actual spray conditions using hand-held knapsack sprayers. Comparison between measured and predicted drift values using three existing empirical equations showed important underestimation. However, after their optimization based on measured drift information, the equations showed a strong predictive power for this study area and the study conditions. The most suitable curve to assess mean relative drift was the IMAG calculator after optimization.

  8. Control of the white-pine weevil with insecticidal emulsions

    Treesearch

    David Crosby

    1958-01-01

    Excellent control of the white-pine weevil in young white pine plantations, by applying concentrated lead arsenate spray with knapsack sprayers, was demonstrated and reported several years ago. Since then, research has shown that a number of newer insecticides, used as emulsions, are also very effective.

  9. Straight Privilege: Unpacking the (Still) Invisible Knapsack

    ERIC Educational Resources Information Center

    Tollefson, Kaia

    2010-01-01

    Several unearned benefits attending straight privilege are listed, prefaced by two main arguments. First, it is argued that the rampant heterosexism in the U.S. is largely attributable to many Americans' framing of heterosexism as a matter of religious freedom rather than as a form of bigotry. It is further argued that educators' elimination of…

  10. Relatedness-based Multi-Entity Summarization

    PubMed Central

    Gunaratna, Kalpa; Yazdavar, Amir Hossein; Thirunarayan, Krishnaprasad; Sheth, Amit; Cheng, Gong

    2017-01-01

    Representing world knowledge in a machine processable format is important as entities and their descriptions have fueled tremendous growth in knowledge-rich information processing platforms, services, and systems. Prominent applications of knowledge graphs include search engines (e.g., Google Search and Microsoft Bing), email clients (e.g., Gmail), and intelligent personal assistants (e.g., Google Now, Amazon Echo, and Apple’s Siri). In this paper, we present an approach that can summarize facts about a collection of entities by analyzing their relatedness in preference to summarizing each entity in isolation. Specifically, we generate informative entity summaries by selecting: (i) inter-entity facts that are similar and (ii) intra-entity facts that are important and diverse. We employ a constrained knapsack problem solving approach to efficiently compute entity summaries. We perform both qualitative and quantitative experiments and demonstrate that our approach yields promising results compared to two other stand-alone state-of-the-art entity summarization approaches. PMID:29051696

  11. Optimal Sensor Allocation for Fault Detection and Isolation

    NASA Technical Reports Server (NTRS)

    Azam, Mohammad; Pattipati, Krishna; Patterson-Hine, Ann

    2004-01-01

    Automatic fault diagnostic schemes rely on various types of sensors (e.g., temperature, pressure, vibration, etc) to measure the system parameters. Efficacy of a diagnostic scheme is largely dependent on the amount and quality of information available from these sensors. The reliability of sensors, as well as the weight, volume, power, and cost constraints, often makes it impractical to monitor a large number of system parameters. An optimized sensor allocation that maximizes the fault diagnosibility, subject to specified weight, volume, power, and cost constraints is required. Use of optimal sensor allocation strategies during the design phase can ensure better diagnostics at a reduced cost for a system incorporating a high degree of built-in testing. In this paper, we propose an approach that employs multiple fault diagnosis (MFD) and optimization techniques for optimal sensor placement for fault detection and isolation (FDI) in complex systems. Keywords: sensor allocation, multiple fault diagnosis, Lagrangian relaxation, approximate belief revision, multidimensional knapsack problem.

  12. McIntosh as Synecdoche: How Teacher Education's Focus on White Privilege Undermines Antiracism

    ERIC Educational Resources Information Center

    Lensmire, Timothy J.; McManimon, Shannon K.; Tierney, Jessica Dockter; Lee-Nichols, Mary E.; Casey, Zachary A.; Lensmire, Audrey; Davis, Bryan M.

    2013-01-01

    In this article, members of the Midwest Critical Whiteness Collective argue that Peggy McIntosh's seminal "knapsack" article acts as a synecdoche, or as a stand-in, for all the antiracist work to be done in teacher education and that this limits our understanding and possibilities for action. The authors develop this argument by…

  13. Clustering of 3D-Structure Similarity Based Network of Secondary Metabolites Reveals Their Relationships with Biological Activities.

    PubMed

    Ohtana, Yuki; Abdullah, Azian Azamimi; Altaf-Ul-Amin, Md; Huang, Ming; Ono, Naoaki; Sato, Tetsuo; Sugiura, Tadao; Horai, Hisayuki; Nakamura, Yukiko; Morita Hirai, Aki; Lange, Klaus W; Kibinge, Nelson K; Katsuragi, Tetsuo; Shirai, Tsuyoshi; Kanaya, Shigehiko

    2014-12-01

    Developing database systems connecting diverse species based on omics is the most important theme in big data biology. To attain this purpose, we have developed KNApSAcK Family Databases, which are utilized in a number of researches in metabolomics. In the present study, we have developed a network-based approach to analyze relationships between 3D structure and biological activity of metabolites consisting of four steps as follows: construction of a network of metabolites based on structural similarity (Step 1), classification of metabolites into structure groups (Step 2), assessment of statistically significant relations between structure groups and biological activities (Step 3), and 2-dimensional clustering of the constructed data matrix based on statistically significant relations between structure groups and biological activities (Step 4). Applying this method to a data set consisting of 2072 secondary metabolites and 140 biological activities reported in KNApSAcK Metabolite Activity DB, we obtained 983 statistically significant structure group-biological activity pairs. As a whole, we systematically analyzed the relationship between 3D-chemical structures of metabolites and biological activities. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. An integrated quality function deployment and capital budgeting methodology for occupational safety and health as a systems thinking approach: the case of the construction industry.

    PubMed

    Bas, Esra

    2014-07-01

    In this paper, an integrated methodology for Quality Function Deployment (QFD) and a 0-1 knapsack model is proposed for occupational safety and health as a systems thinking approach. The House of Quality (HoQ) in QFD methodology is a systematic tool to consider the inter-relationships between two factors. In this paper, three HoQs are used to consider the interrelationships between tasks and hazards, hazards and events, and events and preventive/protective measures. The final priority weights of events are defined by considering their project-specific preliminary weights, probability of occurrence, and effects on the victim and the company. The priority weights of the preventive/protective measures obtained in the last HoQ are fed into a 0-1 knapsack model for the investment decision. Then, the selected preventive/protective measures can be adapted to the task design. The proposed step-by-step methodology can be applied to any stage of a project to design the workplace for occupational safety and health, and continuous improvement for safety is endorsed by the closed loop characteristic of the integrated methodology. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Proceedings of the second SISAL users` conference

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feo, J T; Frerking, C; Miller, P J

    1992-12-01

    This report contains papers on the following topics: A sisal code for computing the fourier transform on S{sub N}; five ways to fill your knapsack; simulating material dislocation motion in sisal; candis as an interface for sisal; parallelisation and performance of the burg algorithm on a shared-memory multiprocessor; use of genetic algorithm in sisal to solve the file design problem; implementing FFT`s in sisal; programming and evaluating the performance of signal processing applications in the sisal programming environment; sisal and Von Neumann-based languages: translation and intercommunication; an IF2 code generator for ADAM architecture; program partitioning for NUMA multiprocessor computer systems;more » mapping functional parallelism on distributed memory machines; implicit array copying: prevention is better than cure ; mathematical syntax for sisal; an approach for optimizing recursive functions; implementing arrays in sisal 2.0; Fol: an object oriented extension to the sisal language; twine: a portable, extensible sisal execution kernel; and investigating the memory performance of the optimizing sisal compiler.« less

  16. Hybridization of decomposition and local search for multiobjective optimization.

    PubMed

    Ke, Liangjun; Zhang, Qingfu; Battiti, Roberto

    2014-10-01

    Combining ideas from evolutionary algorithms, decomposition approaches, and Pareto local search, this paper suggests a simple yet efficient memetic algorithm for combinatorial multiobjective optimization problems: memetic algorithm based on decomposition (MOMAD). It decomposes a combinatorial multiobjective problem into a number of single objective optimization problems using an aggregation method. MOMAD evolves three populations: 1) population P(L) for recording the current solution to each subproblem; 2) population P(P) for storing starting solutions for Pareto local search; and 3) an external population P(E) for maintaining all the nondominated solutions found so far during the search. A problem-specific single objective heuristic can be applied to these subproblems to initialize the three populations. At each generation, a Pareto local search method is first applied to search a neighborhood of each solution in P(P) to update P(L) and P(E). Then a single objective local search is applied to each perturbed solution in P(L) for improving P(L) and P(E), and reinitializing P(P). The procedure is repeated until a stopping condition is met. MOMAD provides a generic hybrid multiobjective algorithmic framework in which problem specific knowledge, well developed single objective local search and heuristics and Pareto local search methods can be hybridized. It is a population based iterative method and thus an anytime algorithm. Extensive experiments have been conducted in this paper to study MOMAD and compare it with some other state-of-the-art algorithms on the multiobjective traveling salesman problem and the multiobjective knapsack problem. The experimental results show that our proposed algorithm outperforms or performs similarly to the best so far heuristics on these two problems.

  17. An Auction-Based Spectrum Leasing Mechanism for Mobile Macro-Femtocell Networks of IoT.

    PubMed

    Chen, Xin; Xing, Lei; Qiu, Tie; Li, Zhuo

    2017-02-16

    The Internet of Things (IoT) is a vision of the upcoming society. It can provide pervasive communication between two or more entities using 4G-LTE (Long Term Evolution) communication technology. In 4G-LTE networks, there are two important problems: helping manage the spectrum demands of IoT devices and achieving much more revenue with the limited resource. This paper proposes a pricing framework to investigate the spectrum leasing in mobile heterogeneous networks with single macrocell and multiple femtocells. We modeled the leasing procedure between the macrocell service provider (MSP) and femtocell holders (FHs) as an auction to motivate the MSP to lease its spectrum resource. All FHs act as the bidders, and the monopolist MSP acts as the auctioneer. In the auction, FHs submit their bids to rent the spectrum resource so that they can make a profit by selling it to their subscribers. The MSP determines the spectrum leasing amount and chooses the winning FHs by solving the dynamic programming-based 0-1 knapsack problem. In our proposed framework, we focus on the spectrum pricing strategy and revenue maximization of the MSP. The simulation results show that the proposed scheme provides effective motivation for the MSP to lease the spectrum to FHs, and both the MSP and FHs can benefit from spectrum leasing.

  18. The effect of a career choice guidance on self-reported psychological problems

    PubMed Central

    Kunnen, E. S.

    2014-01-01

    Late adolescents with career choice problems often have psychological problems as well. The starting point of this study was the question of career choice counselors whether potential clients with career choice problems and psychological problems could be accepted in career choice intervention, or whether it was better to advise them to seek help for their psychological problems. We investigated whether a successful career choice intervention reduced psychological problems, and whether this program was equally effective in participants with low and with high levels of psychological problems. Participants were 45 Dutch students (age 17–24) with career choice problems. They had above average levels of self-reported psychological problems before the start of the intervention. These problems decreased significantly following the intervention. With regard to vocational commitment development, the intervention was equally effective for participants with low or average and with (very) high levels of psychological problems before the start of the intervention. PMID:24926278

  19. Generic Learning-Based Ensemble Framework for Small Sample Size Face Recognition in Multi-Camera Networks.

    PubMed

    Zhang, Cuicui; Liang, Xuefeng; Matsuyama, Takashi

    2014-12-08

    Multi-camera networks have gained great interest in video-based surveillance systems for security monitoring, access control, etc. Person re-identification is an essential and challenging task in multi-camera networks, which aims to determine if a given individual has already appeared over the camera network. Individual recognition often uses faces as a trial and requires a large number of samples during the training phrase. This is difficult to fulfill due to the limitation of the camera hardware system and the unconstrained image capturing conditions. Conventional face recognition algorithms often encounter the "small sample size" (SSS) problem arising from the small number of training samples compared to the high dimensionality of the sample space. To overcome this problem, interest in the combination of multiple base classifiers has sparked research efforts in ensemble methods. However, existing ensemble methods still open two questions: (1) how to define diverse base classifiers from the small data; (2) how to avoid the diversity/accuracy dilemma occurring during ensemble. To address these problems, this paper proposes a novel generic learning-based ensemble framework, which augments the small data by generating new samples based on a generic distribution and introduces a tailored 0-1 knapsack algorithm to alleviate the diversity/accuracy dilemma. More diverse base classifiers can be generated from the expanded face space, and more appropriate base classifiers are selected for ensemble. Extensive experimental results on four benchmarks demonstrate the higher ability of our system to cope with the SSS problem compared to the state-of-the-art system.

  20. Generic Learning-Based Ensemble Framework for Small Sample Size Face Recognition in Multi-Camera Networks

    PubMed Central

    Zhang, Cuicui; Liang, Xuefeng; Matsuyama, Takashi

    2014-01-01

    Multi-camera networks have gained great interest in video-based surveillance systems for security monitoring, access control, etc. Person re-identification is an essential and challenging task in multi-camera networks, which aims to determine if a given individual has already appeared over the camera network. Individual recognition often uses faces as a trial and requires a large number of samples during the training phrase. This is difficult to fulfill due to the limitation of the camera hardware system and the unconstrained image capturing conditions. Conventional face recognition algorithms often encounter the “small sample size” (SSS) problem arising from the small number of training samples compared to the high dimensionality of the sample space. To overcome this problem, interest in the combination of multiple base classifiers has sparked research efforts in ensemble methods. However, existing ensemble methods still open two questions: (1) how to define diverse base classifiers from the small data; (2) how to avoid the diversity/accuracy dilemma occurring during ensemble. To address these problems, this paper proposes a novel generic learning-based ensemble framework, which augments the small data by generating new samples based on a generic distribution and introduces a tailored 0–1 knapsack algorithm to alleviate the diversity/accuracy dilemma. More diverse base classifiers can be generated from the expanded face space, and more appropriate base classifiers are selected for ensemble. Extensive experimental results on four benchmarks demonstrate the higher ability of our system to cope with the SSS problem compared to the state-of-the-art system. PMID:25494350

  1. Optimality and stability of symmetric evolutionary games with applications in genetic selection.

    PubMed

    Huang, Yuanyuan; Hao, Yiping; Wang, Min; Zhou, Wen; Wu, Zhijun

    2015-06-01

    Symmetric evolutionary games, i.e., evolutionary games with symmetric fitness matrices, have important applications in population genetics, where they can be used to model for example the selection and evolution of the genotypes of a given population. In this paper, we review the theory for obtaining optimal and stable strategies for symmetric evolutionary games, and provide some new proofs and computational methods. In particular, we review the relationship between the symmetric evolutionary game and the generalized knapsack problem, and discuss the first and second order necessary and sufficient conditions that can be derived from this relationship for testing the optimality and stability of the strategies. Some of the conditions are given in different forms from those in previous work and can be verified more efficiently. We also derive more efficient computational methods for the evaluation of the conditions than conventional approaches. We demonstrate how these conditions can be applied to justifying the strategies and their stabilities for a special class of genetic selection games including some in the study of genetic disorders.

  2. Hoechst and Wacker plan joint venture in PVC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, I.

    1992-12-02

    Restructuring of Europe's petrochemical industry has taken a further step with the announcement that Hoechst (Frankfurt) and Wacker Chemie (Munich) are planning a joint venture in polyvinyl chloride (PVC). The venture would include production, R D, sales and marketing, plus both companies' PVC recycling activities. However, their vinyl chloride monomer (VCM) plants, and Hoechst's Kalle PVC film business, have been left out. Erich Schnitzler, head of Hoechst's PVC business unit, does not anticipate problems with the European Community's competition directorate. We are both among the middle-sized European PVC producers, and together we would have a 9%-10% market share. Our jointmore » venture would not limit competition. Both partners are hoping for approval from Brussels in first-quarter 1993. Hoechst has 255,000 m.t./year of PVC capacity at Gendorfand Knapsack, while Wacker has 365,000 m.t./year at Burghausen and Cologne. All the units, except Wacker's Cologne plant, are back integrated to VCM. The joint venture would buy VCM from the two parent companies and on the merchant market.« less

  3. Commanders Responsibilities in the Operations Process During the 1864 Red River Expedition

    DTIC Science & Technology

    2015-05-21

    1999), 340. (Hereafter referred to as J.C.C.W.). 20 J.C.C.W., 278. 6 Major General Frederick Steele , 17,000 troops from the Department of the...Assistant Quartermaster Captain D .N. Welch noted “the navy is seizing all that cotton they can get hold of. Every gun -boat is loaded with cotton...then precipitated an increasing withdrawal, turned into an all-out rout, of the Union forces as “ Guns , knapsacks, blankets—everything was thrown away by

  4. A Comparision of Heuristic Methods Used in Hierarchical Production Planning.

    DTIC Science & Technology

    1979-03-01

    literature: Equalization— of—Run—Out—Ti mes ( EROT ) (12], Winters ( 18 ] , Hex and Meal (lii, and Knap- sack [1] . Figure 2 displays a flow chart...forecast error mus t be greater than 24% for this difference to be noticed. Hax—Meal outperformed the EROT with forecast error between 18 and 23% by more...planning frame- work: the Equalization—of—Run—Out—Time approach (12], the Winters approach [ 18 ], the Hax—Meal approach [lii, and the Knapsack approach (1

  5. Knapsack - TOPSIS Technique for Vertical Handover in Heterogeneous Wireless Network

    PubMed Central

    2015-01-01

    In a heterogeneous wireless network, handover techniques are designed to facilitate anywhere/anytime service continuity for mobile users. Consistent best-possible access to a network with widely varying network characteristics requires seamless mobility management techniques. Hence, the vertical handover process imposes important technical challenges. Handover decisions are triggered for continuous connectivity of mobile terminals. However, bad network selection and overload conditions in the chosen network can cause fallout in the form of handover failure. In order to maintain the required Quality of Service during the handover process, decision algorithms should incorporate intelligent techniques. In this paper, a new and efficient vertical handover mechanism is implemented using a dynamic programming method from the operation research discipline. This dynamic programming approach, which is integrated with the Technique to Order Preference by Similarity to Ideal Solution (TOPSIS) method, provides the mobile user with the best handover decisions. Moreover, in this proposed handover algorithm a deterministic approach which divides the network into zones is incorporated into the network server in order to derive an optimal solution. The study revealed that this method is found to achieve better performance and QoS support to users and greatly reduce the handover failures when compared to the traditional TOPSIS method. The decision arrived at the zone gateway using this operational research analytical method (known as the dynamic programming knapsack approach together with Technique to Order Preference by Similarity to Ideal Solution) yields remarkably better results in terms of the network performance measures such as throughput and delay. PMID:26237221

  6. Knapsack--TOPSIS Technique for Vertical Handover in Heterogeneous Wireless Network.

    PubMed

    Malathy, E M; Muthuswamy, Vijayalakshmi

    2015-01-01

    In a heterogeneous wireless network, handover techniques are designed to facilitate anywhere/anytime service continuity for mobile users. Consistent best-possible access to a network with widely varying network characteristics requires seamless mobility management techniques. Hence, the vertical handover process imposes important technical challenges. Handover decisions are triggered for continuous connectivity of mobile terminals. However, bad network selection and overload conditions in the chosen network can cause fallout in the form of handover failure. In order to maintain the required Quality of Service during the handover process, decision algorithms should incorporate intelligent techniques. In this paper, a new and efficient vertical handover mechanism is implemented using a dynamic programming method from the operation research discipline. This dynamic programming approach, which is integrated with the Technique to Order Preference by Similarity to Ideal Solution (TOPSIS) method, provides the mobile user with the best handover decisions. Moreover, in this proposed handover algorithm a deterministic approach which divides the network into zones is incorporated into the network server in order to derive an optimal solution. The study revealed that this method is found to achieve better performance and QoS support to users and greatly reduce the handover failures when compared to the traditional TOPSIS method. The decision arrived at the zone gateway using this operational research analytical method (known as the dynamic programming knapsack approach together with Technique to Order Preference by Similarity to Ideal Solution) yields remarkably better results in terms of the network performance measures such as throughput and delay.

  7. Multi-Criteria Knapsack Problem for Disease Selection in an Observation Ward

    NASA Astrophysics Data System (ADS)

    Lurkittikul, N.; Kittithreerapronchai, O.

    2014-06-01

    The aging population and the introduction of Thailand universal healthcare have increased inpatients and outpatients to public hospitals, particularly to a hospital that provides special and comprehensive health services. Many inpatient wards have experienced large influx of inpatients as the hospitals have to admit all patients regardless their conditions. These overcrowding wards cause stress to medical staffs, block access between medical departments, hospital-acquired infections, and ineffective uses of resources. One way to manage such inundated inpatient is to select some patients whose conditions require less clinical attention or whose lengths of stay are predictable and short and, then, place them at an observation ward. This intermediate ward increases turnover of beds and reduces unnecessary paperwork as patients are considered to be outpatients. In this article, we studied inpatient data of a tertiary care hospital in which an observation ward was considered to alleviate the overcrowding problem at Internal Medicine Department. The analysis of data showed that the hospital can balance inpatient flow by managing a group of patients who is admitted because of treatments ordered by its special clinics. Having explored several alternatives, we suggested patient selection criteria and proposed a layout at an observation ward. The hospital should increase medical beds in a new building ward because the current observation ward can handle 27.3% of total short stay patients, while the observation ward is projected to handle 80% of total short stay patients.

  8. Optimizing Medical Kits for Spaceflight

    NASA Technical Reports Server (NTRS)

    Keenan, A. B,; Foy, Millennia; Myers, G.

    2014-01-01

    The Integrated Medical Model (IMM) is a probabilistic model that estimates medical event occurrences and mission outcomes for different mission profiles. IMM simulation outcomes describing the impact of medical events on the mission may be used to optimize the allocation of resources in medical kits. Efficient allocation of medical resources, subject to certain mass and volume constraints, is crucial to ensuring the best outcomes of in-flight medical events. We implement a new approach to this medical kit optimization problem. METHODS We frame medical kit optimization as a modified knapsack problem and implement an algorithm utilizing a dynamic programming technique. Using this algorithm, optimized medical kits were generated for 3 different mission scenarios with the goal of minimizing the probability of evacuation and maximizing the Crew Health Index (CHI) for each mission subject to mass and volume constraints. Simulation outcomes using these kits were also compared to outcomes using kits optimized..RESULTS The optimized medical kits generated by the algorithm described here resulted in predicted mission outcomes more closely approached the unlimited-resource scenario for Crew Health Index (CHI) than the implementation in under all optimization priorities. Furthermore, the approach described here improves upon in reducing evacuation when the optimization priority is minimizing the probability of evacuation. CONCLUSIONS This algorithm provides an efficient, effective means to objectively allocate medical resources for spaceflight missions using the Integrated Medical Model.

  9. An Auction-Based Spectrum Leasing Mechanism for Mobile Macro-Femtocell Networks of IoT

    PubMed Central

    Chen, Xin; Xing, Lei; Qiu, Tie; Li, Zhuo

    2017-01-01

    The Internet of Things (IoT) is a vision of the upcoming society. It can provide pervasive communication between two or more entities using 4G-LTE (Long Term Evolution) communication technology. In 4G-LTE networks, there are two important problems: helping manage the spectrum demands of IoT devices and achieving much more revenue with the limited resource. This paper proposes a pricing framework to investigate the spectrum leasing in mobile heterogeneous networks with single macrocell and multiple femtocells. We modeled the leasing procedure between the macrocell service provider (MSP) and femtocell holders (FHs) as an auction to motivate the MSP to lease its spectrum resource. All FHs act as the bidders, and the monopolist MSP acts as the auctioneer. In the auction, FHs submit their bids to rent the spectrum resource so that they can make a profit by selling it to their subscribers. The MSP determines the spectrum leasing amount and chooses the winning FHs by solving the dynamic programming-based 0–1 knapsack problem. In our proposed framework, we focus on the spectrum pricing strategy and revenue maximization of the MSP. The simulation results show that the proposed scheme provides effective motivation for the MSP to lease the spectrum to FHs, and both the MSP and FHs can benefit from spectrum leasing. PMID:28212317

  10. Liquid Fertilizer Spraying Performance Using A Knapsack Power Sprayer On Soybean Field

    NASA Astrophysics Data System (ADS)

    Gatot, P.; Anang, R.

    2018-05-01

    An effort for increasing soybean production can be conducted by applying liquid fertilizer on soybean cultivation field. The objective of this research was to determine liquid fertilizer spraying performance using knapsack power sprayer TASCO TF-900 on a soybean cultivation field. Performances test were conducted in the Laboratory of Spraying Test and on a soybean cultivation field to determine (1) effective spraying width, (2) droplets diameter, (3) droplets density, (4) effective spraying discharge rate, and (5) effective field capacity of spraying. The research was conducted using 2 methods: (1) one-nozzle spraying, and (2) four- nozzles spraying. Results of the research showed that at a constant pressure of 900 kPa effective spraying width using one-nozzle spraying and four-nozzles spraying were 0.62 m and 1.10 m. A bigger effective spraying width was resulted in a bigger average effective spraying discharge rate and average effective spraying field capacity of 4.52 l/min and 83.92 m2/min on forward walking speed range of 0.94 m/s up to 1.77 m/s. On the contrary, bigger effective spraying width was result in bigger droplets diameter of 502.73 μm and a smaller droplets density of 98.39 droplets/cm2, whereas smaller effective spraying width was resulted in a smaller droplets diameter of 367.09 μm and a bigger droplets density of 350.53 droplets/cm2. One-nozzle spraying method produced a better spraying quality than four-nozzles spraying method, although four-nozzles spraying was resulted in a bigger effective field capacity of spraying.

  11. Particle swarm optimization algorithm for optimizing assignment of blood in blood banking system.

    PubMed

    Olusanya, Micheal O; Arasomwan, Martins A; Adewumi, Aderemi O

    2015-01-01

    This paper reports the performance of particle swarm optimization (PSO) for the assignment of blood to meet patients' blood transfusion requests for blood transfusion. While the drive for blood donation lingers, there is need for effective and efficient management of available blood in blood banking systems. Moreover, inherent danger of transfusing wrong blood types to patients, unnecessary importation of blood units from external sources, and wastage of blood products due to nonusage necessitate the development of mathematical models and techniques for effective handling of blood distribution among available blood types in order to minimize wastages and importation from external sources. This gives rise to the blood assignment problem (BAP) introduced recently in literature. We propose a queue and multiple knapsack models with PSO-based solution to address this challenge. Simulation is based on sets of randomly generated data that mimic real-world population distribution of blood types. Results obtained show the efficiency of the proposed algorithm for BAP with no blood units wasted and very low importation, where necessary, from outside the blood bank. The result therefore can serve as a benchmark and basis for decision support tools for real-life deployment.

  12. Step by Step: Biology Undergraduates' Problem-Solving Procedures during Multiple-Choice Assessment

    ERIC Educational Resources Information Center

    Prevost, Luanna B.; Lemons, Paula P.

    2016-01-01

    This study uses the theoretical framework of domain-specific problem solving to explore the procedures students use to solve multiple-choice problems about biology concepts. We designed several multiple-choice problems and administered them on four exams. We trained students to produce written descriptions of how they solved the problem, and this…

  13. A model for solving the prescribed burn planning problem.

    PubMed

    Rachmawati, Ramya; Ozlen, Melih; Reinke, Karin J; Hearne, John W

    2015-01-01

    The increasing frequency of destructive wildfires, with a consequent loss of life and property, has led to fire and land management agencies initiating extensive fuel management programs. This involves long-term planning of fuel reduction activities such as prescribed burning or mechanical clearing. In this paper, we propose a mixed integer programming (MIP) model that determines when and where fuel reduction activities should take place. The model takes into account multiple vegetation types in the landscape, their tolerance to frequency of fire events, and keeps track of the age of each vegetation class in each treatment unit. The objective is to minimise fuel load over the planning horizon. The complexity of scheduling fuel reduction activities has led to the introduction of sophisticated mathematical optimisation methods. While these approaches can provide optimum solutions, they can be computationally expensive, particularly for fuel management planning which extends across the landscape and spans long term planning horizons. This raises the question of how much better do exact modelling approaches compare to simpler heuristic approaches in their solutions. To answer this question, the proposed model is run using an exact MIP (using commercial MIP solver) and two heuristic approaches that decompose the problem into multiple single-period sub problems. The Knapsack Problem (KP), which is the first heuristic approach, solves the single period problems, using an exact MIP approach. The second heuristic approach solves the single period sub problem using a greedy heuristic approach. The three methods are compared in term of model tractability, computational time and the objective values. The model was tested using randomised data from 711 treatment units in the Barwon-Otway district of Victoria, Australia. Solutions for the exact MIP could be obtained for up to a 15-year planning only using a standard implementation of CPLEX. Both heuristic approaches can solve significantly larger problems, involving 100-year or even longer planning horizons. Furthermore there are no substantial differences in the solutions produced by the three approaches. It is concluded that for practical purposes a heuristic method is to be preferred to the exact MIP approach.

  14. Risk Selection, Risk Adjustment and Choice: Concepts and Lessons from the Americas

    PubMed Central

    Ellis, Randall P.; Fernandez, Juan Gabriel

    2013-01-01

    Interest has grown worldwide in risk adjustment and risk sharing due to their potential to contain costs, improve fairness, and reduce selection problems in health care markets. Significant steps have been made in the empirical development of risk adjustment models, and in the theoretical foundations of risk adjustment and risk sharing. This literature has often modeled the effects of risk adjustment without highlighting the institutional setting, regulations, and diverse selection problems that risk adjustment is intended to fix. Perhaps because of this, the existing literature and their recommendations for optimal risk adjustment or optimal payment systems are sometimes confusing. In this paper, we present a unified way of thinking about the organizational structure of health care systems, which enables us to focus on two key dimensions of markets that have received less attention: what choices are available that may lead to selection problems, and what financial or regulatory tools other than risk adjustment are used to influence these choices. We specifically examine the health care systems, choices, and problems in four countries: the US, Canada, Chile, and Colombia, and examine the relationship between selection-related efficiency and fairness problems and the choices that are allowed in each country, and discuss recent regulatory reforms that affect choices and selection problems. In this sample, countries and insurance programs with more choices have more selection problems. PMID:24284351

  15. Cascaded Optimization for a Persistent Data Ferrying Unmanned Aircraft

    NASA Astrophysics Data System (ADS)

    Carfang, Anthony

    This dissertation develops and assesses a cascaded method for designing optimal periodic trajectories and link schedules for an unmanned aircraft to ferry data between stationary ground nodes. This results in a fast solution method without the need to artificially constrain system dynamics. Focusing on a fundamental ferrying problem that involves one source and one destination, but includes complex vehicle and Radio-Frequency (RF) dynamics, a cascaded structure to the system dynamics is uncovered. This structure is exploited by reformulating the nonlinear optimization problem into one that reduces the independent control to the vehicle's motion, while the link scheduling control is folded into the objective function and implemented as an optimal policy that depends on candidate motion control. This formulation is proven to maintain optimality while reducing computation time in comparison to traditional ferry optimization methods. The discrete link scheduling problem takes the form of a combinatorial optimization problem that is known to be NP-Hard. A derived necessary condition for optimality guides the development of several heuristic algorithms, specifically the Most-Data-First Algorithm and the Knapsack Adaptation. These heuristics are extended to larger ferrying scenarios, and assessed analytically and through Monte Carlo simulation, showing better throughput performance in the same order of magnitude of computation time in comparison to other common link scheduling policies. The cascaded optimization method is implemented with a novel embedded software system on a small, unmanned aircraft to validate the simulation results with field experiments. To address the sensitivity of results on trajectory tracking performance, a system that combines motion and link control with waypoint-based navigation is developed and assessed through field experiments. The data ferrying algorithms are further extended by incorporating a Gaussian process to opportunistically learn the RF environment. By continuously improving RF models, the cascaded planner can continually improve the ferrying system's overall performance.

  16. Mathematical marriages: intercourse between mathematics and Semiotic choice.

    PubMed

    Wagner, Roy

    2009-04-01

    This paper examines the interaction between Semiotic choices and the presentation and solution of a family of contemporary mathematical problems centred around the so-called 'stable marriage problem'. I investigate how a socially restrictive choice of signs impacts mathematical production both in terms of problem formation and of solutions. I further note how the choice of gendered language ends up constructing a reality, which duplicates the very structural framework that it imported into mathematical analysis in the first place. I go on to point out some semiotic lines of flight from this interlocking grip of mathematics and gendered language.

  17. Mastery matters: consumer choice, psychiatric symptoms and problematic substance use among adults with histories of homelessness.

    PubMed

    Greenwood, Ronni Michelle; Manning, Rachel M

    2017-05-01

    Previous research demonstrated the importance of consumer choice and mastery to residential stability and psychiatric functioning for adults with histories of homelessness. In the present study, we investigated whether these relationships hold, even in the context of problem-related substance misuse. Questionnaire data were collected in Ireland from 101 residents of long-term homeless accommodation in 2010. Hayes' PROCESS macro for mediation and moderation analysis in SPSS was employed to test our hypotheses. Findings demonstrated that the indirect effect of choice through mastery on psychiatric functioning was stronger for individuals with more recent problem-related substance use than for those with no or distant histories of problem-related substance use. Our findings confirm that consumer choice in housing and services is important to homeless services users' recovery experiences. Because of its relationship with mastery, consumer choice in housing and services protects homeless services users' psychiatric functioning, especially when substance use-related choices have had negative consequences. Our findings suggest that if homeless services take away consumer choice when substance use causes problems, they may actually undermine, rather than foster, service users' psychiatric functioning. © 2016 John Wiley & Sons Ltd.

  18. Domain-specific rationality in human choices: violations of utility axioms and social contexts.

    PubMed

    Wang, X T

    1996-07-01

    This study presents a domain-specific view of human decision rationality. It explores social and ecological domain-specific psychological mechanisms underlying choice biases and violations of utility axioms. Results from both the USA and China revealed a social group domain-specific choice pattern. The irrational preference reversal in a hypothetical life-death decision problem (a classical example of framing effects) was eliminated by providing a small group or family context in which most subjects favored a risky choice option regardless of the positive/negative framing of choice outcomes. The risk preference data also indicate that the subjective scope of small group domain is larger for Chinese subjects, suggesting that human choice mechanisms are sensitive to culturally specific features of group living. A further experiment provided evidence that perceived fairness might be one major factor regulating the choice preferences found in small group (kith-and-kin) contexts. Finally, the violation of the stochastic dominance axiom of the rational theory of choice was predicted and tested. The violations were found only when the "life-death" problem was presented in small group contexts; the strongest violation was found in a family context. These results suggest that human decisions and choices are regulated by domain-specific choice mechanisms designed to solve evolutionary recurrent and adaptively important problems.

  19. Early Design Choices: Capture, Model, Integrate, Analyze, Simulate

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.

    2004-01-01

    I. Designs are constructed incrementally to meet requirements and solve problems: a) Requirements types: objectives, scenarios, constraints, ilities. etc. b) Problem/issue types: risk/safety, cost/difficulty, interaction, conflict, etc. II. Capture requirements, problems and solutions: a) Collect design and analysis products and make them accessible for integration and analysis; b) Link changes in design requirements, problems and solutions; and c) Harvest design data for design models and choice structures. III. System designs are constructed by multiple groups designing interacting subsystems a) Diverse problems, choice criteria, analysis methods and point solutions. IV. Support integration and global analysis of repercussions: a) System implications of point solutions; b) Broad analysis of interactions beyond totals of mass, cost, etc.

  20. Pesticide risk assessment: A study on inhalation and dermal exposure to 2,4-D and paraquat among Malaysian paddy farmers.

    PubMed

    Baharuddin, Mohd Rafee B; Sahid, Ismail B; Noor, Mohamad Azhar B Mohd; Sulaiman, Norela; Othman, Fadzil

    2011-01-01

    A cross-section analytical study was conducted to evaluate the risk of pesticide exposure to those applying the Class II pesticides 2,4-D and paraquat in the paddy-growing areas of Kerian, Perak, Malaysia. It investigated the influence of weather on exposure as well as documented health problems commonly related to pesticide exposure. Potential inhalation and dermal exposure for 140 paddy farmers (handlers of pesticides) were assessed. Results showed that while temperature and humidity affected exposure, windspeed had the strongest impact on pesticide exposure via inhalation. However, the degree of exposure to both herbicides via inhalation was below the permissible exposure limits set by United States National Institute of Occupational Safety and Health (NIOSH). Dermal Exposure Assessment Method (DREAM) readings showed that dermal exposure with manual spraying ranged from moderate to high. With motorized sprayers, however, the level of dermal exposure ranged from low to moderate. Dermal exposure was significantly negatively correlated with the usage of protective clothing. Various types of deleterious health effects were detected among users of manual knapsack sprayers. Long-term spraying activities were positively correlated with increasing levels of the gamma-glutamyl transpeptidase (GGT) liver enzyme. The type of spraying equipment, usage of proper protective clothing and adherence to correct spraying practices were found to be the most important factors influencing the degree of pesticide exposure among those applying pesticides.

  1. Mass and Volume Optimization of Space Flight Medical Kits

    NASA Technical Reports Server (NTRS)

    Keenan, A. B.; Foy, Millennia Hope; Myers, Jerry

    2014-01-01

    Resource allocation is a critical aspect of space mission planning. All resources, including medical resources, are subject to a number of mission constraints such a maximum mass and volume. However, unlike many resources, there is often limited understanding in how to optimize medical resources for a mission. The Integrated Medical Model (IMM) is a probabilistic model that estimates medical event occurrences and mission outcomes for different mission profiles. IMM simulates outcomes and describes the impact of medical events in terms of lost crew time, medical resource usage, and the potential for medically required evacuation. Previously published work describes an approach that uses the IMM to generate optimized medical kits that maximize benefit to the crew subject to mass and volume constraints. We improve upon the results obtained previously and extend our approach to minimize mass and volume while meeting some benefit threshold. METHODS We frame the medical kit optimization problem as a modified knapsack problem and implement an algorithm utilizing dynamic programming. Using this algorithm, optimized medical kits were generated for 3 mission scenarios with the goal of minimizing the medical kit mass and volume for a specified likelihood of evacuation or Crew Health Index (CHI) threshold. The algorithm was expanded to generate medical kits that maximize likelihood of evacuation or CHI subject to mass and volume constraints. RESULTS AND CONCLUSIONS In maximizing benefit to crew health subject to certain constraints, our algorithm generates medical kits that more closely resemble the unlimited-resource scenario than previous approaches which leverage medical risk information generated by the IMM. Our work here demonstrates that this algorithm provides an efficient and effective means to objectively allocate medical resources for spaceflight missions and provides an effective means of addressing tradeoffs in medical resource allocations and crew mission success parameters.

  2. Individual Differences in Strategy Use on Division Problems: Mental versus Written Computation

    ERIC Educational Resources Information Center

    Hickendorff, Marian; van Putten, Cornelis M.; Verhelst, Norman D.; Heiser, Willem J.

    2010-01-01

    Individual differences in strategy use (choice and accuracy) were analyzed. A sample of 362 Grade 6 students solved complex division problems under 2 different conditions. In the choice condition students were allowed to use either a mental or a written strategy. In the subsequent no-choice condition, they were required to use a written strategy.…

  3. SOFIA's Choice: Automating the Scheduling of Airborne Observations

    NASA Technical Reports Server (NTRS)

    Frank, Jeremy; Norvig, Peter (Technical Monitor)

    1999-01-01

    This paper describes the problem of scheduling observations for an airborne telescope. Given a set of prioritized observations to choose from, and a wide range of complex constraints governing legitimate choices and orderings, how can we efficiently and effectively create a valid flight plan which supports high priority observations? This problem is quite different from scheduling problems which are routinely solved automatically in industry. For instance, the problem requires making choices which lead to other choices later, and contains many interacting complex constraints over both discrete and continuous variables. Furthermore, new types of constraints may be added as the fundamental problem changes. As a result of these features, this problem cannot be solved by traditional scheduling techniques. The problem resembles other problems in NASA and industry, from observation scheduling for rovers and other science instruments to vehicle routing. The remainder of the paper is organized as follows. In 2 we describe the observatory in order to provide some background. In 3 we describe the problem of scheduling a single flight. In 4 we compare flight planning and other scheduling problems and argue that traditional techniques are not sufficient to solve this problem. We also mention similar complex scheduling problems which may benefit from efforts to solve this problem. In 5 we describe an approach for solving this problem based on research into a similar problem, that of scheduling observations for a space-borne probe. In 6 we discuss extensions of the flight planning problem as well as other problems which are similar to flight planning. In 7 we conclude and discuss future work.

  4. Effect of the Presence of External Representations on Accuracy and Reaction Time in Solving Mathematical Double-Choice Problems by Students of Different Levels of Instruction

    ERIC Educational Resources Information Center

    Leikin, Roza; Leikin, Mark; Waisman, Ilana; Shaul, Shelley

    2013-01-01

    This study explores the effects of the "presence of external representations of a mathematical object" (ERs) on problem solving performance associated with short double-choice problems. The problems were borrowed from secondary school algebra and geometry, and the ERs were either formulas, graphs of functions, or drawings of geometric…

  5. Visual Attention for Solving Multiple-Choice Science Problem: An Eye-Tracking Analysis

    ERIC Educational Resources Information Center

    Tsai, Meng-Jung; Hou, Huei-Tse; Lai, Meng-Lung; Liu, Wan-Yi; Yang, Fang-Ying

    2012-01-01

    This study employed an eye-tracking technique to examine students' visual attention when solving a multiple-choice science problem. Six university students participated in a problem-solving task to predict occurrences of landslide hazards from four images representing four combinations of four factors. Participants' responses and visual attention…

  6. The framing of decisions and the psychology of choice.

    PubMed

    Tversky, A; Kahneman, D

    1981-01-30

    The psychological principles that govern the perception of decision problems and the evaluation of probabilities and outcomes produce predictable shifts of preference when the same problem is framed in different ways. Reversals of preference are demonstrated in choices regarding monetary outcomes, both hypothetical and real, and in questions pertaining to the loss of human lives. The effects of frames on preferences are compared to the effects of perspectives on perceptual appearance. The dependence of preferences on the formulation of decision problems is a significant concern for the theory of rational choice.

  7. Reversing the Use of Hobson's Choice: Culturally Relevant Assessment and Treatment Practices for Culturally and Linguistically Diverse Learners with Problem Behaviors

    ERIC Educational Resources Information Center

    Obiakor, Festus E.; Gibson, Lenwood

    2015-01-01

    Hobson's Choice is a psychological philosophy that prescribes a "take-it-or-leave-it" approach when addressing the problematic behaviors of students. Logically, this choice provides a traditional order in the classroom and gives teachers and service providers the sole power and authority to manage problem behaviors. For many students…

  8. On the Policy Structure and Orientation of Governing the School Choice Problem in China's Basic Education

    ERIC Educational Resources Information Center

    Xu, Zhi-yong

    2009-01-01

    The paper analyzes the nature of the basic education, and points out that the scarcity, disparity and exclusiveness to a certain degree form the inner reasons of school choice in China. In review of the policy evolution of governing the school choice problems, and analyzing the policy framework of the current stage, the paper holds that expanding…

  9. An analysis of choice making in the assessment of young children with severe behavior problems.

    PubMed

    Harding, J W; Wacker, D P; Berg, W K; Cooper, L J; Asmus, J; Mlela, K; Muller, J

    1999-01-01

    We examined how positive and negative reinforcement influenced time allocation, occurrence of problem behavior, and completion of parent instructions during a concurrent choice assessment with 2 preschool-aged children who displayed severe problem behavior in their homes. The children were given a series of concurrent choice options that varied availability of parent attention, access to preferred toys, and presentation of parent instructions. The results showed that both children consistently allocated their time to choice areas that included parent attention when no instructions were presented. When parent attention choice areas included the presentation of instructions, the children displayed differential patterns of behavior that appeared to be influenced by the presence or absence of preferred toys. The results extended previous applications of reinforcer assessment procedures by analyzing the relative influence of both positive and negative reinforcement within a concurrent-operants paradigm.

  10. Patterns of Problem-Solving in Children's Literacy and Arithmetic

    ERIC Educational Resources Information Center

    Farrington-Flint, Lee; Vanuxem-Cotterill, Sophie; Stiller, James

    2009-01-01

    Patterns of problem-solving among 5-to-7 year-olds' were examined on a range of literacy (reading and spelling) and arithmetic-based (addition and subtraction) problem-solving tasks using verbal self-reports to monitor strategy choice. The results showed higher levels of variability in the children's strategy choice across Years 1 and 2 on the…

  11. Energy in America: Progress and Potential.

    ERIC Educational Resources Information Center

    American Petroleum Inst., Washington, DC.

    An overview of America's energy situation is presented with emphasis on recent progress, the risk of depending upon foreign oil, and policy choices. Section one reviews the energy problems of the 1970s, issues of the 1980s, concerns for the future, and choices that if made today could alleviate future problems. Section two examines past problems,…

  12. METHODOLOGICAL ISSUES IN THE ANALYSIS OF RESIDENTIAL PREFERENCES, RESIDENTIAL MOBILITY, AND NEIGHBORHOOD CHANGE1

    PubMed Central

    Bruch, Elizabeth E.; Mare, Robert D.

    2011-01-01

    This paper reviews methods for analyzing both individual preferences and choices about where to live, and the implications of these choices for residential patterns. Although these methods are discussed in the context of residential choice, they can be applied more broadly to individual choices in a range of social contexts where behavior is interdependent. We review a variety of types of data on residential preferences and mobility and discuss appropriate statistical models for these data. We discuss the analysis of ranked and other types of clustered data; functional form issues; problems of unobserved heterogeneity in individuals and in neighborhoods; and strengths and weaknesses of stated preference data versus observations of actual mobility behavior. We also discuss specific problems with residential mobility data, including the treatment of one’s current location as a potential choice, how to specify the choice set of potential movers, the aggregation of units (such as dwelling units into neighborhoods) and the need to take account of variations in neighborhood size, the problem of very large choice sets and possible sampling solutions; and the link between residential mobility and patterns of neighborhood change. PMID:23476098

  13. Asymmetrically dominated choice problems, the isolation hypothesis and random incentive mechanisms.

    PubMed

    Cox, James C; Sadiraj, Vjollca; Schmidt, Ulrich

    2014-01-01

    This paper presents an experimental study of the random incentive mechanisms which are a standard procedure in economic and psychological experiments. Random incentive mechanisms have several advantages but are incentive-compatible only if responses to the single tasks are independent. This is true if either the independence axiom of expected utility theory or the isolation hypothesis of prospect theory holds. We present a simple test of this in the context of choice under risk. In the baseline (one task) treatment we observe risk behavior in a given choice problem. We show that by integrating a second, asymmetrically dominated choice problem in a random incentive mechanism risk behavior can be manipulated systematically. This implies that the isolation hypothesis is violated and the random incentive mechanism does not elicit true preferences in our example.

  14. Intertemporal bargaining predicts moral behavior, even in anonymous, one-shot economic games.

    PubMed

    Ainslie, George

    2013-02-01

    To the extent that acting fairly is in an individual’s long-term interest, short-term impulses to cheat present a self-control problem. The only effective solution is to interpret the problem as a variant of repeated prisoner’s dilemma, with each choice as a test case predicting future choices. Moral choice appears to be the product of a contract because it comes from self-enforcing intertemporal cooperation.

  15. Development of Proportional Reasoning: Where Young Children Go Wrong

    PubMed Central

    Boyer, Ty W.; Levine, Susan C.; Huttenlocher, Janellen

    2008-01-01

    Previous studies have found that children have difficulty solving proportional reasoning problems involving discrete units until 10- to 12-years of age, but can solve parallel problems involving continuous quantities by 6-years of age. The present studies examine where children go wrong in processing proportions that involve discrete quantities. A computerized proportional equivalence choice task was administered to kindergartners through fourth-graders in Study 1, and to first- and third-graders in Study 2. Both studies involved four between-subjects conditions that were formed by pairing continuous and discrete target proportions with continuous and discrete choice alternatives. In Study 1, target and choice alternatives were presented simultaneously and in Study 2 target and choice alternatives were presented sequentially. In both studies, children performed significantly worse when both the target and choice alternatives were represented with discrete quantities than when either or both of the proportions involved continuous quantities. Taken together, these findings indicate that children go astray on proportional reasoning problems involving discrete units only when a numerical match is possible, suggesting that their difficulty is due to an overextension of numerical equivalence concepts to proportional equivalence problems. PMID:18793078

  16. Mass Spectra-Based Framework for Automated Structural Elucidation of Metabolome Data to Explore Phytochemical Diversity

    PubMed Central

    Matsuda, Fumio; Nakabayashi, Ryo; Sawada, Yuji; Suzuki, Makoto; Hirai, Masami Y.; Kanaya, Shigehiko; Saito, Kazuki

    2011-01-01

    A novel framework for automated elucidation of metabolite structures in liquid chromatography–mass spectrometer metabolome data was constructed by integrating databases. High-resolution tandem mass spectra data automatically acquired from each metabolite signal were used for database searches. Three distinct databases, KNApSAcK, ReSpect, and the PRIMe standard compound database, were employed for the structural elucidation. The outputs were retrieved using the CAS metabolite identifier for identification and putative annotation. A simple metabolite ontology system was also introduced to attain putative characterization of the metabolite signals. The automated method was applied for the metabolome data sets obtained from the rosette leaves of 20 Arabidopsis accessions. Phenotypic variations in novel Arabidopsis metabolites among these accessions could be investigated using this method. PMID:22645535

  17. Hobson's Choice: Illusory Intervention Choice for Culturally and Linguistically Diverse Learners with Problem Behaviors

    ERIC Educational Resources Information Center

    Obiakor, Festus E.

    2012-01-01

    Hobson's choice is a "no-choice" choice that gives general and special educators the traditional impetus to do what they want in classrooms. While there is some "goodness" in having this power and audacity to control whatever happens in classrooms, it does not allow for creativity, flexibility, adaptability, modification, especially in behavior…

  18. Agency and Choice in Education: Does School Choice Enhance the Work Effort of Teachers?

    ERIC Educational Resources Information Center

    Rapp, Geoffrey C.

    2000-01-01

    Investigates effects of school-choice laws on U.S. teachers' work incentives, using 1993-94 Schools and Staffing Survey data. Examines whether school system competitiveness works to solve the principal-agent problem in education. Results are mixed, but suggest that one type of choice policy--intradistrict choice--enhances teacher motivation.…

  19. Bridging the Gap Between Planning and Scheduling

    NASA Technical Reports Server (NTRS)

    Smith, David E.; Frank, Jeremy; Jonsson, Ari K.; Norvig, Peter (Technical Monitor)

    2000-01-01

    Planning research in Artificial Intelligence (AI) has often focused on problems where there are cascading levels of action choice and complex interactions between actions. In contrast. Scheduling research has focused on much larger problems where there is little action choice, but the resulting ordering problem is hard. In this paper, we give an overview of M planning and scheduling techniques, focusing on their similarities, differences, and limitations. We also argue that many difficult practical problems lie somewhere between planning and scheduling, and that neither area has the right set of tools for solving these vexing problems.

  20. [Delayed reactions of active avoidance in white rats under conditions of an alternative choice].

    PubMed

    Ioseliani, T K; Sikharulidze, N I; Kadagishvili, A Ia; Mitashvili, E G

    1995-01-01

    It was shown that if the rats had been learned and then tested using conventional pain punishment of erroneous choice they were able to solve the problem of alternative choice only in the period of immediate action of conditioned stimuli. If the pain punishment for erroneously chosen compartment had not been applied in animal learning and testing, rats successfully solved the problem of alternative choice even after 5-second delay. Introduction of pain punishment led to the frustration of earlier elaborated delayed avoidance reactions. Analysis of the obtained results allows us to argue that the apparent incapability of white rats for solving the problems of delayed avoidance is caused by simultaneous action of two different mechanisms, i.e., those of the active and passive avoidance rather than short-term memory deficit.

  1. Step by Step: Biology Undergraduates’ Problem-Solving Procedures during Multiple-Choice Assessment

    PubMed Central

    Prevost, Luanna B.; Lemons, Paula P.

    2016-01-01

    This study uses the theoretical framework of domain-specific problem solving to explore the procedures students use to solve multiple-choice problems about biology concepts. We designed several multiple-choice problems and administered them on four exams. We trained students to produce written descriptions of how they solved the problem, and this allowed us to systematically investigate their problem-solving procedures. We identified a range of procedures and organized them as domain general, domain specific, or hybrid. We also identified domain-general and domain-specific errors made by students during problem solving. We found that students use domain-general and hybrid procedures more frequently when solving lower-order problems than higher-order problems, while they use domain-specific procedures more frequently when solving higher-order problems. Additionally, the more domain-specific procedures students used, the higher the likelihood that they would answer the problem correctly, up to five procedures. However, if students used just one domain-general procedure, they were as likely to answer the problem correctly as if they had used two to five domain-general procedures. Our findings provide a categorization scheme and framework for additional research on biology problem solving and suggest several important implications for researchers and instructors. PMID:27909021

  2. "Parents a dead end life": The main experiences of parents of children with leukemia.

    PubMed

    Jadidi, Rahmatollah; Hekmatpou, Davood; Eghbali, Aziz; Memari, Fereshteh; Anbari, Zohreh

    2014-11-01

    The quantitative studies show that due to the widespread prevalence, high death rate, high treatment expenses, and long hospital stay, leukemia influences the families and their children to a great extent. In this regard, no qualitative study has been conducted in Iran. So, this study was conducted in Arak in 2011 with the aim of expressing the experiences of the parents whose children suffered from leukemia. Using qualitative research approach, by applying content analysis method, 22 participants were interviewed in two educational hospitals during 2 months. The study was started by purposive sampling and continued by theoretical one. The data were analyzed based on the content analysis method. Data analysis showed that insolvency, knapsack problems, cancer secrecy, trust on God, self-sacrifice, adaptation, medical malpractice, and hospital facilities were the level 3 codes of parents' experiences and "parents a dead end life" was the main theme of this study. In this study, the experiences of the parents whose children suffered from cancer were studied deeply by the use of qualitative method, especially by the use of resources syncretism rather than studying quantitatively. Parents a dead end life emerged as the main theme of this study, emphasizing the necessity of paying further attention to the parents. On the other hand, making more use of parents' experiences and encouraging them helps make the treatment more effective. It is suggested that these experiences be shared with parents in the form of pamphlets distributed right at the beginning of the treatment process.

  3. Illegal Drugs: What Should We Do Now? An Issue Book.

    ERIC Educational Resources Information Center

    National Issues Forums, Dayton, OH.

    Increasing frustration with the illegal drug problem is fueling public discussion about the effectiveness of the nation's antidrug efforts. This document offers three choices for dealing with the drug abuse problem in the Untied States. Each choice presents "what can be done" and information "in support" and "in…

  4. Uncertainty reasoning in expert systems

    NASA Technical Reports Server (NTRS)

    Kreinovich, Vladik

    1993-01-01

    Intelligent control is a very successful way to transform the expert's knowledge of the type 'if the velocity is big and the distance from the object is small, hit the brakes and decelerate as fast as possible' into an actual control. To apply this transformation, one must choose appropriate methods for reasoning with uncertainty, i.e., one must: (1) choose the representation for words like 'small', 'big'; (2) choose operations corresponding to 'and' and 'or'; (3) choose a method that transforms the resulting uncertain control recommendations into a precise control strategy. The wrong choice can drastically affect the quality of the resulting control, so the problem of choosing the right procedure is very important. From a mathematical viewpoint these choice problems correspond to non-linear optimization and are therefore extremely difficult. In this project, a new mathematical formalism (based on group theory) is developed that allows us to solve the problem of optimal choice and thus: (1) explain why the existing choices are really the best (in some situations); (2) explain a rather mysterious fact that fuzzy control (i.e., control based on the experts' knowledge) is often better than the control by these same experts; and (3) give choice recommendations for the cases when traditional choices do not work.

  5. Kolkata Paise Restaurant Problem: An Introduction

    NASA Astrophysics Data System (ADS)

    Ghosh, Asim; Biswas, Soumyajyoti; Chatterjee, Arnab; Chakrabarti, Anindya Sundar; Naskar, Tapan; Mitra, Manipushpak; Chakrabarti, Bikas K.

    We discuss several stochastic optimization strategies in games with many players having large number of choices (Kolkata Paise Restaurant Problem) and two choices (minority game problem). It is seen that a stochastic crowd avoiding strategy gives very efficient utilization in KPR problem. A slightly modified strategy in the minority game problem gives full utilization but the dynamics stops after reaching full efficiency, thereby making the utilization helpful for only about half of the population (those in minority). We further discuss the ways in which the dynamics may be continued and the utilization becomes effective for all the agents keeping fluctuation arbitrarily small.

  6. Lost in the crowd? Using eye-tracking to investigate the effect of complexity on attribute non-attendance in discrete choice experiments.

    PubMed

    Spinks, Jean; Mortimer, Duncan

    2016-02-03

    The provision of additional information is often assumed to improve consumption decisions, allowing consumers to more accurately weigh the costs and benefits of alternatives. However, increasing the complexity of decision problems may prompt changes in information processing. This is particularly relevant for experimental methods such as discrete choice experiments (DCEs) where the researcher can manipulate the complexity of the decision problem. The primary aims of this study are (i) to test whether consumers actually process additional information in an already complex decision problem, and (ii) consider the implications of any such 'complexity-driven' changes in information processing for design and analysis of DCEs. A discrete choice experiment (DCE) is used to simulate a complex decision problem; here, the choice between complementary and conventional medicine for different health conditions. Eye-tracking technology is used to capture the number of times and the duration that a participant looks at any part of a computer screen during completion of DCE choice sets. From this we can analyse what has become known in the DCE literature as 'attribute non-attendance' (ANA). Using data from 32 participants, we model the likelihood of ANA as a function of choice set complexity and respondent characteristics using fixed and random effects models to account for repeated choice set completion. We also model whether participants are consistent with regard to which characteristics (attributes) they consider across choice sets. We find that complexity is the strongest predictor of ANA when other possible influences, such as time pressure, ordering effects, survey specific effects and socio-demographic variables (including proxies for prior experience with the decision problem) are considered. We also find that most participants do not apply a consistent information processing strategy across choice sets. Eye-tracking technology shows promise as a way of obtaining additional information from consumer research, improving DCE design, and informing the design of policy measures. With regards to DCE design, results from the present study suggest that eye-tracking data can identify the point at which adding complexity (and realism) to DCE choice scenarios becomes self-defeating due to unacceptable increases in ANA. Eye-tracking data therefore has clear application in the construction of guidelines for DCE design and during piloting of DCE choice scenarios. With regards to design of policy measures such as labelling requirements for CAM and conventional medicines, the provision of additional information has the potential to make difficult decisions even harder and may not have the desired effect on decision-making.

  7. INDIVIDUAL DIFFERENCES IN IMPULSIVE CHOICE AND TIMING IN RATS

    PubMed Central

    Galtress, Tiffany; Garcia, Ana; Kirkpatrick, Kimberly

    2012-01-01

    Individual differences in impulsive choice behavior have been linked to a variety of behavioral problems including substance abuse, smoking, gambling, and poor financial decision-making. Given the potential importance of individual differences in impulsive choice as a predictor of behavioral problems, the present study sought to measure the extent of individual differences in a normal sample of hooded Lister rats. Three experiments utilized variations of a delay discounting task to measure the degree of variation in impulsive choice behavior across individual rats. The individual differences accounted for 22–55% of the variance in choice behavior across the three experiments. In Experiments 2 and 3, the individual differences were still apparent when behavior was measured across multiple choice points. Large individual differences in the rate of responding, and modest individual differences in timing of responding were also observed during occasional peak trials. The individual differences in timing and rate, however, did not correlate consistently with individual differences in choice behavior. This suggests that a variety of factors may affect choice behavior, response rate, and response timing. PMID:22851792

  8. The impact of two multiple-choice question formats on the problem-solving strategies used by novices and experts.

    PubMed

    Coderre, Sylvain P; Harasym, Peter; Mandin, Henry; Fick, Gordon

    2004-11-05

    Pencil-and-paper examination formats, and specifically the standard, five-option multiple-choice question, have often been questioned as a means for assessing higher-order clinical reasoning or problem solving. This study firstly investigated whether two paper formats with differing number of alternatives (standard five-option and extended-matching questions) can test problem-solving abilities. Secondly, the impact of the alternatives number on psychometrics and problem-solving strategies was examined. Think-aloud protocols were collected to determine the problem-solving strategy used by experts and non-experts in answering Gastroenterology questions, across the two pencil-and-paper formats. The two formats demonstrated equal ability in testing problem-solving abilities, while the number of alternatives did not significantly impact psychometrics or problem-solving strategies utilized. These results support the notion that well-constructed multiple-choice questions can in fact test higher order clinical reasoning. Furthermore, it can be concluded that in testing clinical reasoning, the question stem, or content, remains more important than the number of alternatives.

  9. Designing a Transportation System for a Parent Choice School District: A Transportation Supervisor's Handbook.

    ERIC Educational Resources Information Center

    Paller, Alan; And Others

    This study was commissioned to investigate the special transportation problems in parent-choice school districts and to prepare a handbook to assist transportation supervisors in overcoming these problems. Intended for school districts that have alternative schools, open enrollment plans, magnet schools, or other kinds of parent and student choice…

  10. Incorporating Choice and Preferred Activities into Classwide Instruction

    ERIC Educational Resources Information Center

    Kern, Lee; State, Talida M.

    2009-01-01

    It is often said that the best intervention strategies prevent problem behaviors from starting in the first place. Two preventative strategies that teachers can use are choice making and incorporating preferred activities into classwide instruction. Not only do these strategies avoid problem behaviors, but teachers also find them easy to use in…

  11. Influence of an Intermediate Option on the Description-Experience Gap and Information Search

    PubMed Central

    Sharma, Neha; Debnath, Shoubhik; Dutt, Varun

    2018-01-01

    Research shows that people tend to overweight small probabilities in description and underweight them in experience, thereby leading to a different pattern of choices between description and experience; a phenomenon known as the Description-Experience (DE) gap. However, little is known on how the addition of an intermediate option and contextual framing influences the DE gap and people’s search strategies. This paper tests the effects of an intermediate option and contextual framing on the DE gap and people’s search strategies, where problems require search for information before a consequential choice. In the first experiment, 120 participants made choice decisions across investment problems that differed in the absence or presence of an intermediate option. Results showed that adding an intermediate option did not reduce the DE gap on the maximizing option across a majority of problems. There were a large majority of choices for the intermediate option. Furthermore, there was an increase in switching between options due to the presence of the intermediate option. In the second experiment, 160 participants made choice decisions in problems like those presented in experiment 1; however, problems lacked the investment framing. Results replicated findings from the first experiment and showed a similar DE gap on the maximizing option in a majority of problems in both the absence and presence of the intermediate option. Again, there were a large majority of choices for the intermediate option. Also, there was an increase in switching between options due to the presence of the intermediate option. Meta-analyses revealed that the absence or presence of the intermediate option created certain differences in the strength of frequency and recency processes. Also, a single natural-mean heuristic model was able to account for the experimental results across both experiments. We discuss implications of our findings to consequential decisions made after information search. PMID:29643821

  12. Influence of an Intermediate Option on the Description-Experience Gap and Information Search.

    PubMed

    Sharma, Neha; Debnath, Shoubhik; Dutt, Varun

    2018-01-01

    Research shows that people tend to overweight small probabilities in description and underweight them in experience, thereby leading to a different pattern of choices between description and experience; a phenomenon known as the Description-Experience (DE) gap. However, little is known on how the addition of an intermediate option and contextual framing influences the DE gap and people's search strategies. This paper tests the effects of an intermediate option and contextual framing on the DE gap and people's search strategies, where problems require search for information before a consequential choice. In the first experiment, 120 participants made choice decisions across investment problems that differed in the absence or presence of an intermediate option. Results showed that adding an intermediate option did not reduce the DE gap on the maximizing option across a majority of problems. There were a large majority of choices for the intermediate option. Furthermore, there was an increase in switching between options due to the presence of the intermediate option. In the second experiment, 160 participants made choice decisions in problems like those presented in experiment 1; however, problems lacked the investment framing. Results replicated findings from the first experiment and showed a similar DE gap on the maximizing option in a majority of problems in both the absence and presence of the intermediate option. Again, there were a large majority of choices for the intermediate option. Also, there was an increase in switching between options due to the presence of the intermediate option. Meta-analyses revealed that the absence or presence of the intermediate option created certain differences in the strength of frequency and recency processes. Also, a single natural-mean heuristic model was able to account for the experimental results across both experiments. We discuss implications of our findings to consequential decisions made after information search.

  13. Genetic Algorithms for Multiple-Choice Problems

    NASA Astrophysics Data System (ADS)

    Aickelin, Uwe

    2010-04-01

    This thesis investigates the use of problem-specific knowledge to enhance a genetic algorithm approach to multiple-choice optimisation problems.It shows that such information can significantly enhance performance, but that the choice of information and the way it is included are important factors for success.Two multiple-choice problems are considered.The first is constructing a feasible nurse roster that considers as many requests as possible.In the second problem, shops are allocated to locations in a mall subject to constraints and maximising the overall income.Genetic algorithms are chosen for their well-known robustness and ability to solve large and complex discrete optimisation problems.However, a survey of the literature reveals room for further research into generic ways to include constraints into a genetic algorithm framework.Hence, the main theme of this work is to balance feasibility and cost of solutions.In particular, co-operative co-evolution with hierarchical sub-populations, problem structure exploiting repair schemes and indirect genetic algorithms with self-adjusting decoder functions are identified as promising approaches.The research starts by applying standard genetic algorithms to the problems and explaining the failure of such approaches due to epistasis.To overcome this, problem-specific information is added in a variety of ways, some of which are designed to increase the number of feasible solutions found whilst others are intended to improve the quality of such solutions.As well as a theoretical discussion as to the underlying reasons for using each operator,extensive computational experiments are carried out on a variety of data.These show that the indirect approach relies less on problem structure and hence is easier to implement and superior in solution quality.

  14. Some unsolved problems in discrete mathematics and mathematical cybernetics

    NASA Astrophysics Data System (ADS)

    Korshunov, Aleksei D.

    2009-10-01

    There are many unsolved problems in discrete mathematics and mathematical cybernetics. Writing a comprehensive survey of such problems involves great difficulties. First, such problems are rather numerous and varied. Second, they greatly differ from each other in degree of completeness of their solution. Therefore, even a comprehensive survey should not attempt to cover the whole variety of such problems; only the most important and significant problems should be reviewed. An impersonal choice of problems to include is quite hard. This paper includes 13 unsolved problems related to combinatorial mathematics and computational complexity theory. The problems selected give an indication of the author's studies for 50 years; for this reason, the choice of the problems reviewed here is, to some extent, subjective. At the same time, these problems are very difficult and quite important for discrete mathematics and mathematical cybernetics. Bibliography: 74 items.

  15. Zusammenarbeit aus Sicht eines outgesourcten Instandhalters

    NASA Astrophysics Data System (ADS)

    Grüßer, Stefan; Loeven, Heinz-Wilhelm

    Dauerhafter Unternehmenserfolg ist nur mit einer fortschrittlichen Instandhaltung zu erzielen. Durch den enormen Kostendruck infolge der Globalisierung und die Innovationssprünge auf der technischen Seite wird auch die Frage nach der modernen Organisationsform für die Instandhaltung gestellt. Eine Möglichkeit der Kostenoptimierung ist das Outsourcing von Instandhaltungsleistungen. Hierbei ist es unerlässlich, dass sich die Mitarbeiter zum Dienstleister entwickeln. In diesem Beitrag wird die Entwicklung der InfraServ Knapsack von einer internen Instandhaltungsabteilung hin zu einem Industriellen Dienstleister beschrieben und Aspekte der Zusammenarbeit mit externen Kunden aus der Sicht des outgesourcten Instandhalters geschildert. Es werden die wichtigen Entwicklungsschritte zur Dienstleistungsorientierung der früheren Eigeninstandhaltung aufgezeigt. Dieser Beitrag ist nicht als "Königsweg“ zu verstehen, er soll vielmehr anhand der Erfahrungen einer outgesourcten Eigeninstandhaltung Anregungen für die Entwicklung der eigenen Instandhaltungsorganisation liefern.

  16. Freedom to Make Choices for Health: Plus 40 Years

    ERIC Educational Resources Information Center

    Airhihenbuwa, Collins O.; Iwelunmor, Juliet

    2010-01-01

    In the 1969 inaugural issue of the "School Health Review", Douglass J.H. examined four major issues he felt were central to the question of choices one has about health: (1) problems with health care delivery methods; (2) persistent poverty in our population and its impact on health; (3) systemic problems inherent in social and institutional…

  17. The Multiple-Choice Model: Some Solutions for Estimation of Parameters in the Presence of Omitted Responses

    ERIC Educational Resources Information Center

    Abad, Francisco J.; Olea, Julio; Ponsoda, Vicente

    2009-01-01

    This article deals with some of the problems that have hindered the application of Samejima's and Thissen and Steinberg's multiple-choice models: (a) parameter estimation difficulties owing to the large number of parameters involved, (b) parameter identifiability problems in the Thissen and Steinberg model, and (c) their treatment of omitted…

  18. When students can choose easy, medium, or hard homework problems

    NASA Astrophysics Data System (ADS)

    Teodorescu, Raluca E.; Seaton, Daniel T.; Cardamone, Caroline N.; Rayyan, Saif; Abbott, Jonathan E.; Barrantes, Analia; Pawl, Andrew; Pritchard, David E.

    2012-02-01

    We investigate student-chosen, multi-level homework in our Integrated Learning Environment for Mechanics [1] built using the LON-CAPA [2] open-source learning system. Multi-level refers to problems categorized as easy, medium, and hard. Problem levels were determined a priori based on the knowledge needed to solve them [3]. We analyze these problems using three measures: time-per-problem, LON-CAPA difficulty, and item difficulty measured by item response theory. Our analysis of student behavior in this environment suggests that time-per-problem is strongly dependent on problem category, unlike either score-based measures. We also found trends in student choice of problems, overall effort, and efficiency across the student population. Allowing students choice in problem solving seems to improve their motivation; 70% of students worked additional problems for which no credit was given.

  19. The problem of choice: From the voluntary way to Affordable Care Act health insurance exchanges.

    PubMed

    Mulligan, Jessica

    2017-05-01

    This article takes a genealogical and ethnographic approach to the problem of choice, arguing that what choice means has been reworked several times since health insurance first figured prominently in national debates about health reform. Whereas voluntary choice of doctor and hospital used to be framed as an American right, contemporary choice rhetoric includes consumer choice of insurance plan. Understanding who has deployed choice rhetoric and to what ends helps explain how offering choices has become the common sense justification for defending and preserving the exclusionary health care system in the United States. Four case studies derived from 180 enrollment observations at the Rhode Island health insurance exchange conducted from March 2014-January 2017 and interviews with enrollees show how choice is experienced in this latest iteration of health reform. The Affordable Care Act (ACA) of 2010 created new pathways to insurance coverage in the United States. Insurance exchanges were supposed to unleash the power of consumer decision-making through marketplaces where health plans compete on quality, coverage, and price. Consumers, however, contended with confusing insurance terminology and difficult to navigate websites. The ethnography shows that consumers experienced choice as confusing and overwhelming and did not feel "in charge" of their decisions. Instead, unstable employment, changes in income, existing health needs, and bureaucratic barriers shaped their "choices." Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Computational unsteady aerodynamics for lifting surfaces

    NASA Technical Reports Server (NTRS)

    Edwards, John W.

    1988-01-01

    Two dimensional problems are solved using numerical techniques. Navier-Stokes equations are studied both in the vorticity-stream function formulation which appears to be the optimal choice for two dimensional problems, using a storage approach, and in the velocity pressure formulation which minimizes the number of unknowns in three dimensional problems. Analysis shows that compact centered conservative second order schemes for the vorticity equation are the most robust for high Reynolds number flows. Serious difficulties remain in the choice of turbulent models, to keep reasonable CPU efficiency.

  1. Methods of equipment choice in shotcreting

    NASA Astrophysics Data System (ADS)

    Sharapov, R. R.; Yadykina, V. V.; Stepanov, M. A.; Kitukov, B. A.

    2018-03-01

    Shotcrete is widely used in architecture, hydraulic engineering structures, finishing works in tunnels, arc covers and ceilings. The problem of the equipment choice in shotcreting is very important. The main issues influencing the equipment choice are quality improvement and intensification of shotcreting. Main parameters and rational limits of technological characteristic of machines used in solving different problems in shotcreting are described. It is suggested to take into account peculiarities of shotcrete mixing processes and peculiarities of applying these mixtures with compressed air kinetic energy. The described method suggests choosing a mixer with the account of energy capacity, Reynolds number and rotational frequency of the mixing drum. The suggested choice procedure of the equipment nomenclature allows decreasing exploitation costs, increasing the quality of shotcrete and shotcreting in general.

  2. Spontaneous gestures influence strategy choices in problem solving.

    PubMed

    Alibali, Martha W; Spencer, Robert C; Knox, Lucy; Kita, Sotaro

    2011-09-01

    Do gestures merely reflect problem-solving processes, or do they play a functional role in problem solving? We hypothesized that gestures highlight and structure perceptual-motor information, and thereby make such information more likely to be used in problem solving. Participants in two experiments solved problems requiring the prediction of gear movement, either with gesture allowed or with gesture prohibited. Such problems can be correctly solved using either a perceptual-motor strategy (simulation of gear movements) or an abstract strategy (the parity strategy). Participants in the gesture-allowed condition were more likely to use perceptual-motor strategies than were participants in the gesture-prohibited condition. Gesture promoted use of perceptual-motor strategies both for participants who talked aloud while solving the problems (Experiment 1) and for participants who solved the problems silently (Experiment 2). Thus, spontaneous gestures influence strategy choices in problem solving.

  3. Decision making under uncertainty and information processing in positive and negative mood states.

    PubMed

    Mohanty, Sachi Nandan; Suar, Damodar

    2014-08-01

    This study examines whether mood states (a) influence decision making under uncertainty and (b) affect information processing. 200 students at the Indian Institute of Technology Kharagpur participated in this study. Positive mood was induced by showing comedy movie clips to 100 participants and negative mood was induced by showing tragedy movie clips to another 100 participants. The participants were administered a questionnaire containing hypothetical situations of financial gains and losses, and a health risk problem. The participants selected a choice for each situation, and stated the reasons for their choice. Results suggested that the participants preferred cautious choices in the domain of gain and in health risk problems and risky choices in the domain of loss. Analysis of the reasons for the participants' choices suggested more fluency, originality, and flexibility of information in a negative mood compared to a positive mood. A negative (positive) mood state facilitated systematic (heuristic) information processing.

  4. Global Environmental Problems: Implications for U.S. Policy [and] Teacher's Resource Book. Revised. Choices for the 21st Century.

    ERIC Educational Resources Information Center

    Brown Univ., Providence, RI. Thomas J. Watson, Jr. Inst. for International Studies.

    This unit weighs the choices and tradeoffs involved in protecting the environment. The first section of the first booklet is designed to introduce students to the most significant global environmental problems. Part 2 explores humanity's impact on the environment while part 3 examines environmental issues from the political dimension as a…

  5. Informed choice and deaf children: underpinning concepts and enduring challenges.

    PubMed

    Young, Alys; Carr, Gwen; Hunt, Ros; McCracken, Wendy; Skipp, Amy; Tattersall, Helen

    2006-01-01

    This article concerns the first stage of a research and development project that aimed to produce both parent and professional guidelines on the promotion and provision of informed choice for families with deaf children. It begins with a theoretical discussion of the problems associated with the concept of informed choice and deaf child services and then focuses specifically on why a metastudy approach was employed to address both the overcontextualized debate about informed choice when applied to deaf children and the problems associated with its investigation in practice with families and professionals. It presents a detailed analysis of the conceptual relevance of a range of identified studies "outside" the field of deafness. These are ordered according to 2 main conceptual categories and 7 subcategories-(a) the nature of information: "information that is evaluative, not just descriptive"; "the difficulties of information for a purpose"; "the origins and status of information"; and "informed choice and knowledge, not informed choice and information" and (b) parameters and definitions of choice: "informed choice as absolute and relative concept", "preferences and presumptions of rationality", and "informed choice for whom?" Relevant deaf child literature is integrated into the discussion of each conceptual debate in order both to expand and challenge current usage of informed choice as applied to deaf children and families and to delineate possible directions in the planning of the next stage of the main project aimed at producing parent/professional guidelines.

  6. Format Effects of Empirically Derived Multiple-Choice versus Free-Response Instruments When Assessing Graphing Abilities

    ERIC Educational Resources Information Center

    Berg, Craig; Boote, Stacy

    2017-01-01

    Prior graphing research has demonstrated that clinical interviews and free-response instruments produce very different results than multiple-choice instruments, indicating potential validity problems when using multiple-choice instruments to assess graphing skills (Berg & Smith in "Science Education," 78(6), 527-554, 1994). Extending…

  7. Diversity and Choice in School Education: An Alternative View.

    ERIC Educational Resources Information Center

    Walford, Geoffrey

    1996-01-01

    Discusses the difficulties in using cost-benefit analysis in education, examines in detail some of the documents supporting the modified libertarian position, and traces the development of policy on school choice. Documents the various new forms of selection that accompany increased choice and considers problems of social segregation. (MJP)

  8. Preference Reversal: A New Look at an Old Problem

    ERIC Educational Resources Information Center

    Li, Shu

    2006-01-01

    A generalized "weak dominance" approach is used to test the documented preference reversal (PR) phenomenon. This approach simply models risky choice behavior in PR as a choice between the best possible outcomes or a choice between the worst possible outcomes by equating smaller paired outcome difference between bets. The preference…

  9. A Portfolio of the Identities of Young People of the South of Russia under the Conditions of Civilizational Choice

    ERIC Educational Resources Information Center

    Avksent'ev, V. A.; Aksiumov, B. V.

    2012-01-01

    The problem of civilizational choice is one of the most timely and relevant problems of the entire postcommunist world. Most of the states of the former Soviet Union, including Russia, still find themselves in an uncertain zone of transition. The crisis of civilizational identity, far from being overcome, has even deepened as the Soviet past…

  10. Reclassification: Rationale and Problems; Proceedings of a Conference on Reclassification held at the Center of Adult Education, University of Maryland, College Park, April 4 to 6, 1968.

    ERIC Educational Resources Information Center

    Perreault, Jean M., Ed.

    Several factors are involved in the decision to reclassify library collections and several problems and choices must be faced. The discussion of four classification schemes (Dewey Decimal, Library of Congress, Library of Congress subject-headings and Universal Decimal Classification) involved in the choices concerns their structure, currency,…

  11. Pesticide knowledge, practice and attitude and how it affects the health of small-scale farmers in Uganda: a cross-sectional study.

    PubMed

    Oesterlund, Anna H; Thomsen, Jane F; Sekimpi, Deogratias K; Maziina, James; Racheal, Apio; Jørs, Erik

    2014-06-01

    Over the past years there has been an increase in the use of pesticides in developing countries. This study describes pesticide use among small-scale farmers in Uganda and analyses predictors of pesticide poisoning (intoxication) symptoms. A cross-sectional study was conducted using a standardized questionnaire. Some 317 small-scale farmers in two districts in Uganda were interviewed about pesticide use, knowledge and attitude, symptoms of intoxication, personal protective equipment (PPE) and hygiene. The risk of reporting symptoms was analysed using logistic regression analysis. The most frequently used pesticides belonged to WHO class II. The farmers had poor knowledge about pesticide toxicity, and the majority did not use appropriate PPE nor good hygiene when handling pesticides. There was no significant association between the number of times of spraying with pesticides and self-reported symptoms of pesticide poisoning. The only significant association was between blowing and sucking the nozzle of the knapsack sprayer and self-reported symptoms of pesticide intoxication (OR: 2.13. 95% CI: 1.09 - 4.18). Unlike the practice in several other developing countries, small-scale farmers in Uganda do not use the most hazardous pesticides (WHO class 1a and 1b). However use of WHO class II pesticides and those of lower toxicity is seen in combination with inadequate knowledge and practice among the farmers. This poses a danger of acute intoxications, chronic health problems and environmental pollution. Training of farmers in Integrated Pest Management (IPM) methods, use of proper hygiene and personal protective equipment when handling pesticides should be promoted.

  12. “Parents a dead end life”: The main experiences of parents of children with leukemia

    PubMed Central

    Jadidi, Rahmatollah; Hekmatpou, Davood; Eghbali, Aziz; Memari, Fereshteh; Anbari, Zohreh

    2014-01-01

    Background: The quantitative studies show that due to the widespread prevalence, high death rate, high treatment expenses, and long hospital stay, leukemia influences the families and their children to a great extent. In this regard, no qualitative study has been conducted in Iran. So, this study was conducted in Arak in 2011 with the aim of expressing the experiences of the parents whose children suffered from leukemia. Materials and Methods: Using qualitative research approach, by applying content analysis method, 22 participants were interviewed in two educational hospitals during 2 months. The study was started by purposive sampling and continued by theoretical one. The data were analyzed based on the content analysis method. Resluts: Data analysis showed that insolvency, knapsack problems, cancer secrecy, trust on God, self-sacrifice, adaptation, medical malpractice, and hospital facilities were the level 3 codes of parents’ experiences and “parents a dead end life” was the main theme of this study. Conclusion: In this study, the experiences of the parents whose children suffered from cancer were studied deeply by the use of qualitative method, especially by the use of resources syncretism rather than studying quantitatively. Parents a dead end life emerged as the main theme of this study, emphasizing the necessity of paying further attention to the parents. On the other hand, making more use of parents’ experiences and encouraging them helps make the treatment more effective. It is suggested that these experiences be shared with parents in the form of pamphlets distributed right at the beginning of the treatment process. PMID:25558257

  13. Metacognition for strategy selection during arithmetic problem-solving in young and older adults.

    PubMed

    Geurten, Marie; Lemaire, Patrick

    2018-04-19

    We examined participants' strategy choices and metacognitive judgments during arithmetic problem-solving. Metacognitive judgments were collected either prospectively or retrospectively. We tested whether metacognitive judgments are related to strategy choices on the current problems and on the immediately following problems, and age-related differences in relations between metacognition and strategy choices. Data showed that both young and older adults were able to make accurate retrospective, but not prospective, judgments. Moreover, the accuracy of retrospective judgments was comparable in young and older adults when participants had to select and execute the better strategy. Metacognitive accuracy was even higher in older adults when participants had to only select the better strategy. Finally, low-confidence judgments on current items were more frequently followed by better strategy selection on immediately succeeding items than high-confidence judgments in both young and older adults. Implications of these findings to further our understanding of age-related differences and similarities in adults' metacognitive monitoring and metacognitive regulation for strategy selection in the context of arithmetic problem solving are discussed.

  14. Free choice in residential care for older people - A philosophical reflection.

    PubMed

    Nord, Catharina

    2016-04-01

    Free choice in elderly care services is a debated issue. Using the theoretical support of philosophers of free will, this paper explores free choice in relocation to residential care. The three dominant perspectives within this field of philosophy, libertarianism, determinism and compatibilism, are applied from the perspective of the older individual to the process of moving. Empirical data were collected through qualitative interviews with 13 older individuals who had recently moved into residential care. These individuals had made the choice to move following either a health emergency or incremental health problems. In a deterministic perspective they had no alternative to moving, which was the inevitable solution to their various personal problems. A network of people important to them assisted in the move, making the choice possible. However, post-move the interviewees' perspective had changed to a libertarian or compatibilist interpretation, whereby although the circumstances had conferred little freedom regarding the move. The interviewees reported a high degree of self-determination in the process. It appeared that in order to restore self-respect and personal agency, the older individuals had transformed their restricted choice into a choice made of free will or freer will. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Incentives, equity and the Able Chooser Problem.

    PubMed

    Grill, Kalle

    2017-03-01

    Health incentive schemes aim to produce healthier behaviours in target populations. They may do so both by making incentivised options more salient and by making them less costly. Changes in costs only result in healthier behaviour if the individual rationally assesses the cost change and acts accordingly. Not all people do this well. Those who fail to respond rationally to incentives will typically include those who are least able to make prudent choices more generally. This group will typically include the least advantaged more generally, since disadvantage inhibits one's effective ability to choose well and since poor choices tend to cause or aggravate disadvantage. Therefore, within the target population, health benefits to the better off may come at the cost of aggravated inequity. This is one instance of a problem I name the Able Chooser Problem, previously emphasised by Richard Arneson in relation to coercive paternalism. I describe and discuss this problem by distinguishing between policy options and their effects on the choice situation of individuals. Both positive and negative incentives, as well as mandates that are less than perfectly effective, require some sort of rational deliberation and action and so face the Able Chooser Problem. In contrast, effective restriction of what options are physically available, as well as choice context design that makes some options more salient or appealing, does not demand rational agency. These considerations provide an equity-based argument for preferring smart design of our choice and living environment to incentives and mandates. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Multiple Choice Items: How to Gain the Most out of Them.

    ERIC Educational Resources Information Center

    Talmir, Pinchas

    1991-01-01

    Describes how multiple-choice items can be designed and used as an effective diagnostic tool by avoiding their pitfalls and by taking advantage of their potential benefits. The following issues are discussed: correct' versus best answers; construction of diagnostic multiple-choice items; the problem of guessing; the use of justifications of…

  17. Comparison of Difficulties and Reliabilities of Math-Completion and Multiple-Choice Item Formats.

    ERIC Educational Resources Information Center

    Oosterhof, Albert C.; Coats, Pamela K.

    Instructors who develop classroom examinations that require students to provide a numerical response to a mathematical problem are often very concerned about the appropriateness of the multiple-choice format. The present study augments previous research relevant to this concern by comparing the difficulty and reliability of multiple-choice and…

  18. Step by Step: Biology Undergraduates' Problem-Solving Procedures during Multiple-Choice Assessment.

    PubMed

    Prevost, Luanna B; Lemons, Paula P

    2016-01-01

    This study uses the theoretical framework of domain-specific problem solving to explore the procedures students use to solve multiple-choice problems about biology concepts. We designed several multiple-choice problems and administered them on four exams. We trained students to produce written descriptions of how they solved the problem, and this allowed us to systematically investigate their problem-solving procedures. We identified a range of procedures and organized them as domain general, domain specific, or hybrid. We also identified domain-general and domain-specific errors made by students during problem solving. We found that students use domain-general and hybrid procedures more frequently when solving lower-order problems than higher-order problems, while they use domain-specific procedures more frequently when solving higher-order problems. Additionally, the more domain-specific procedures students used, the higher the likelihood that they would answer the problem correctly, up to five procedures. However, if students used just one domain-general procedure, they were as likely to answer the problem correctly as if they had used two to five domain-general procedures. Our findings provide a categorization scheme and framework for additional research on biology problem solving and suggest several important implications for researchers and instructors. © 2016 L. B. Prevost and P. P. Lemons. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  19. Stochastic search, optimization and regression with energy applications

    NASA Astrophysics Data System (ADS)

    Hannah, Lauren A.

    Designing clean energy systems will be an important task over the next few decades. One of the major roadblocks is a lack of mathematical tools to economically evaluate those energy systems. However, solutions to these mathematical problems are also of interest to the operations research and statistical communities in general. This thesis studies three problems that are of interest to the energy community itself or provide support for solution methods: R&D portfolio optimization, nonparametric regression and stochastic search with an observable state variable. First, we consider the one stage R&D portfolio optimization problem to avoid the sequential decision process associated with the multi-stage. The one stage problem is still difficult because of a non-convex, combinatorial decision space and a non-convex objective function. We propose a heuristic solution method that uses marginal project values---which depend on the selected portfolio---to create a linear objective function. In conjunction with the 0-1 decision space, this new problem can be solved as a knapsack linear program. This method scales well to large decision spaces. We also propose an alternate, provably convergent algorithm that does not exploit problem structure. These methods are compared on a solid oxide fuel cell R&D portfolio problem. Next, we propose Dirichlet Process mixtures of Generalized Linear Models (DPGLM), a new method of nonparametric regression that accommodates continuous and categorical inputs, and responses that can be modeled by a generalized linear model. We prove conditions for the asymptotic unbiasedness of the DP-GLM regression mean function estimate. We also give examples for when those conditions hold, including models for compactly supported continuous distributions and a model with continuous covariates and categorical response. We empirically analyze the properties of the DP-GLM and why it provides better results than existing Dirichlet process mixture regression models. We evaluate DP-GLM on several data sets, comparing it to modern methods of nonparametric regression like CART, Bayesian trees and Gaussian processes. Compared to existing techniques, the DP-GLM provides a single model (and corresponding inference algorithms) that performs well in many regression settings. Finally, we study convex stochastic search problems where a noisy objective function value is observed after a decision is made. There are many stochastic search problems whose behavior depends on an exogenous state variable which affects the shape of the objective function. Currently, there is no general purpose algorithm to solve this class of problems. We use nonparametric density estimation to take observations from the joint state-outcome distribution and use them to infer the optimal decision for a given query state. We propose two solution methods that depend on the problem characteristics: function-based and gradient-based optimization. We examine two weighting schemes, kernel-based weights and Dirichlet process-based weights, for use with the solution methods. The weights and solution methods are tested on a synthetic multi-product newsvendor problem and the hour-ahead wind commitment problem. Our results show that in some cases Dirichlet process weights offer substantial benefits over kernel based weights and more generally that nonparametric estimation methods provide good solutions to otherwise intractable problems.

  20. Diagrams Benefit Symbolic Problem-Solving

    ERIC Educational Resources Information Center

    Chu, Junyi; Rittle-Johnson, Bethany; Fyfe, Emily R.

    2017-01-01

    Background: The format of a mathematics problem often influences students' problem-solving performance. For example, providing diagrams in conjunction with story problems can benefit students' understanding, choice of strategy, and accuracy on story problems. However, it remains unclear whether providing diagrams in conjunction with symbolic…

  1. [Determinism and Freedom of Choice in the Brain Functioning].

    PubMed

    Ivanitsky, A M

    2015-01-01

    The problem is considered whether the brain response is completely determined by the stimulus and the personal experience or in some cases the brain is free to choose its behavioral response to achieve the desired goal. The attempt is made to approach to this important philosophical problem basing on modern knowledge about the brain. The paper consists of four parts. In the first part the theoretical views about the free choice problem solving are considered, including views about the freedom of choice as a useful illusion, the hypothesis on appliance of quantum mechanics laws to the brain functioning and the theory of mentalism. In other tree parts consequently the more complicated brain functions such as choice reaction, thinking and creation are analyzed. The general conclusion is that the possibility of quite unpredictable, but sometimes very effective decisions increases when the brain functions are more and more complicated. This fact can be explained with two factors: increasing stochasticity of the brain processes and the role of top-down determinations from mental to neural levels, according to the theory of mentalism.

  2. Strategy Choice in Solving Arithmetic Word Problems: Are There Differences between Students with Learning Disabilities, G-V Poor Performance, and Typical Achievement Students?

    ERIC Educational Resources Information Center

    Gonzalez, Juan E. Jimenez; Espinel, Ana Isabel Garcia

    2002-01-01

    A study was designed to test whether there are differences between Spanish children (ages 7-9) with arithmetic learning disabilities (n=60), garden-variety (G-V) poor performance (n=44), and typical children (n=44) in strategy choice when solving arithmetic word problems. No significant differences were found between children with dyscalculia and…

  3. Interactions among attention-deficit hyperactivity disorder (ADHD) and problem gambling in a probabilistic reward-learning task.

    PubMed

    Abouzari, Mehdi; Oberg, Scott; Gruber, Aaron; Tata, Matthew

    2015-09-15

    Problem gambling is thought to be highly comorbid with attention-deficit hyperactivity disorder (ADHD). We propose that the neurobiological pathologies underlying problem gambling overlap with those in ADHD. In this study, we used a simplified computerized version of the Iowa Gambling Task (IGT) to assess differences in reinforcement-driven choice adaptation among participants with pathological gambling and/or ADHD. The task contained two choice options with different net payouts over the session; a good bet that resulted in a win of +50 points on 60% of trials (and -50 points on 40%), and a bad bet that resulted in +100 points on 40% of the trials (and -100 points on 60%). We quantified participants' preference for the good bet over the session and their sensitivity to reinforcement. Both the control subjects and medicated ADHD nongamblers significantly increased the proportion of good bets over the 400-trial session. Subjects with problem gambling performed worse than controls and ADHD nongamblers, but better than our limited sample of unmedicated ADHD gamblers. Control subjects, medicated ADHD nongamblers, and unmedicated ADHD nongamblers tended to tolerate losses following good bets, whereas unmedicated ADHD gamblers tended to tolerate losses following bad bets. These data reveal that ADHD, particularly when treated with medication, is not associated with poor choices on the IGT, but may exacerbate pathological choices in problem gamblers. It seems that stabilization of dopamine signaling that occurs when ADHD is treated is itself also a treatment for certain forms of problem gambling. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  4. Voice and choice by delegation.

    PubMed

    van de Bovenkamp, Hester; Vollaard, Hans; Trappenburg, Margo; Grit, Kor

    2013-02-01

    In many Western countries, options for citizens to influence public services are increased to improve the quality of services and democratize decision making. Possibilities to influence are often cast into Albert Hirschman's taxonomy of exit (choice), voice, and loyalty. In this article we identify delegation as an important addition to this framework. Delegation gives individuals the chance to practice exit/choice or voice without all the hard work that is usually involved in these options. Empirical research shows that not many people use their individual options of exit and voice, which could lead to inequality between users and nonusers. We identify delegation as a possible solution to this problem, using Dutch health care as a case study to explore this option. Notwithstanding various advantages, we show that voice and choice by delegation also entail problems of inequality and representativeness.

  5. Informed Choice and Deaf Children: Underpinning Concepts and Enduring Challenges

    ERIC Educational Resources Information Center

    Young, Alys; Carr, Gwen; Hunt, Ros; McCracken, Wendy; Skipp, Amy; Tattersall, Helen

    2006-01-01

    This article concerns the first stage of a research and development project that aimed to produce both parent and professional guidelines on the promotion and provision of informed choice for families with deaf children. It begins with a theoretical discussion of the problems associated with the concept of informed choice and deaf child services…

  6. Providing Information to Parents of Children with Mental Health Problems: A Discrete Choice Conjoint Analysis of Professional Preferences

    ERIC Educational Resources Information Center

    Cunningham, Charles E.; Deal, Ken; Rimas, Heather; Chen, Yvonne; Buchanan, Don H.; Sdao-Jarvie, Kathie

    2009-01-01

    We used discrete choice conjoint analysis to model the ways 645 children's mental health (CMH) professionals preferred to provide information to parents seeking CMH services. Participants completed 20 choice tasks presenting experimentally varied combinations of the study's 14 4-level CMH information transfer attributes. Latent class analysis…

  7. The Effect of Positive or Negative Frame on the Choices of Students in School Psychology and Educational Administration.

    ERIC Educational Resources Information Center

    Fagley, N. S.; Miller, Paul M.; Jones, Robert N.

    1999-01-01

    Doctoral students (N=109) in school psychology and educational administration responded to five decision problems whose outcomes were framed either positively as gains or negatively as losses. Frame and profession significantly affected the number of risky choices. Educational administration students made more risky choices than school psychology…

  8. A fair range of choice: justifying maximum patient choice in the British National Health Service.

    PubMed

    Wilmot, Stephen

    2007-06-01

    In this paper I put forward an ethical argument for the provision of extensive patient choice by the British National Health Service. I base this argument on traditional liberal rights to freedom of choice, on a welfare right to health care, and on a view of health as values-based. I argue that choice, to be ethically sustainable on this basis, must be values-based and rational. I also consider whether the British taxpayer may be persuadable with regard to the moral acceptability of patient choice, making use of Rawls' theory of political liberalism in this context. I identify issues that present problems in terms of public acceptance of choice, and also identify a boundary issue with regard to public health choices as against individual choices.

  9. Sociological research on the population awareness regarding ophthalmological care in ukraine.

    PubMed

    Ieremeieva, Tetiana V

    nowadays, there are about 45 million blind individuals and, according to the prognosis, their quantity will reach over 76 million in 2020. In such a way, nowadays ophthalmological problems become more widespread, and the market of the ophthalmological services is not studied enough to understand all the tendencies and processes. was to study the patients' awareness on eye diseases and choice peculiarities of the information sources and medical institutions among various population age groups of Lutsk, Rivne and Ternopil cities. the research was conducted as an anonymous questionnaire survey of respondents according to a specially designed integrated protocol by means of interviewing people at the streets of Lutsk (n=2000), Rivne (n=1500) and Ternopil (n=1500) cities. there was conducted a research on the population awareness concerning vision problems, analysis of social factors and peculiarities of the choice of information sources about eye diseases and factors influencing the choice of a medical institution and an ophthalmologist. It was determined that younger population prefers private medical institutions in almost half of the cases (95% confidence interval (CI) of the private institution choice probability: 0,48-0,52), while older population prefers mainly state ones (95% CI of the choice probability: 0,71-0,74). it was determined depending on the age, the range of people having vision problems varied from 22% in the "under 30 years" population group up to 76% in the "over 60 years" group, although at least 21,5% of the whole population realizing their problems do not address an ophthalmologist.

  10. Sociological research on the population awareness regarding ophthalmological care in ukraine.

    PubMed

    Ieremeieva, Tetiana V

    2016-01-01

    nowadays, there are about 45 million blind individuals and, according to the prognosis, their quantity will reach over 76 million in 2020. In such a way, nowadays ophthalmological problems become more widespread, and the market of the ophthalmological services is not studied enough to understand all the tendencies and processes. was to study the patients' awareness on eye diseases and choice peculiarities of the information sources and medical institutions among various population age groups of Lutsk, Rivne and Ternopil cities. the research was conducted as an anonymous questionnaire survey of respondents according to a specially designed integrated protocol by means of interviewing people at the streets of Lutsk (n=2000), Rivne (n=1500) and Ternopil (n=1500) cities. there was conducted a research on the population awareness concerning vision problems, analysis of social factors and peculiarities of the choice of information sources about eye diseases and factors influencing the choice of a medical institution and an ophthalmologist. It was determined that younger population prefers private medical institutions in almost half of the cases (95% confidence interval (CI) of the private institution choice probability: 0,48-0,52), while older population prefers mainly state ones (95% CI of the choice probability: 0,71-0,74). it was determined depending on the age, the range of people having vision problems varied from 22% in the "under 30 years" population group up to 76% in the "over 60 years" group, although at least 21,5% of the whole population realizing their problems do not address an ophthalmologist.

  11. Drug choice as a self-handicapping strategy in response to noncontingent success.

    PubMed

    Berglas, S; Jones, E E

    1978-04-01

    In two closely related experiments, college student subjects were instructed to choose between a drug that allegedly interfered with performance and a drug that allegedly enhanced performance. This choice was the main dependent measure of the experiment. The drug choice intervened between work on soluble or insoluble problems and a promised retest on similar problems. In Experiment 1, all subjects received success feedback after their initial problem-solving attempts, thus creating one condition in which the success appeared to be accidental (noncontingent on performance) and one in which the success appeared to be contingent on appropriate knowledge. Males in the noncontingent-success condition were alone in preferring the performance-inhibiting drug, presumably because they wished to externalize probable failure on the retest. The predicted effect, however, did not hold for female subjects. Experiment 2 replicated the unique preference shown by males after noncontingent success and showed the critical importance of success feedback.

  12. An information processing view of framing effects: the role of causal schemas in decision making.

    PubMed

    Jou, J; Shanteau, J; Harris, R J

    1996-01-01

    People prefer a sure gain to a probable larger gain when the two choices are presented from a gain perspective, but a probable larger loss to a sure loss when the objectively identical choices are presented from a loss perspective. Such reversals of preference due to the context of the problem are known as framing effects. In the present study, schema activation and subjects' interpretations of the problems were examined as sources of the framing effects. Results showed that such effects could be eliminated by introducing into a problem a causal schema that provided a rationale for the reciprocal relationship between the gains and the losses. Moreover, when subjects were freed from framing they were consistently risk seeking in decisions about human life, but risk averse in decisions about property. Irrationality in choice behaviors and the ecological implication of framing effects are discussed.

  13. Quality of life of people with mental health problems: a synthesis of qualitative research

    PubMed Central

    2012-01-01

    Purpose To identify the domains of quality of life important to people with mental health problems. Method A systematic review of qualitative research undertaken with people with mental health problems using a framework synthesis. Results We identified six domains: well-being and ill-being; control, autonomy and choice; self-perception; belonging; activity; and hope and hopelessness. Firstly, symptoms or ‘ill-being’ were an intrinsic aspect of quality of life for people with severe mental health problems. Additionally, a good quality of life was characterised by the feeling of being in control (particularly of distressing symptoms), autonomy and choice; a positive self-image; a sense of belonging; engagement in meaningful and enjoyable activities; and feelings of hope and optimism. Conversely, a poor quality life, often experienced by those with severe mental health difficulties, was characterized by feelings of distress; lack of control, choice and autonomy; low self-esteem and confidence; a sense of not being part of society; diminished activity; and a sense of hopelessness and demoralization. Conclusions Generic measures fail to address the complexity of quality of life measurement and the broad range of domains important to people with mental health problems. PMID:23173689

  14. Strategies in a symmetric quantum Kolkata restaurant problem

    NASA Astrophysics Data System (ADS)

    Sharif, Puya; Heydari, Hoshang

    2012-12-01

    The Quantum Kolkata restaurant problem is a multiple-choice version of the quantum minority game, where a set of n non-communicating players have to chose between one of m choices. A payoff is granted to the players that make a unique choice. It has previously been shown that shared entanglement and quantum operations can aid the players to coordinate their actions and acquire higher payoffs than is possible with classical randomization. In this paper the initial quantum state is expanded to a family of GHZ-type states and strategies are discussed in terms of possible final outcomes. It is shown that the players individually seek outcomes that maximize the collective good.

  15. Beyond Problem-Based Learning: Using Dynamic PBL in Chemistry

    ERIC Educational Resources Information Center

    Overton, Tina L.; Randles, Christopher A.

    2015-01-01

    This paper describes the development and implementation of a novel pedagogy, dynamic problem-based learning. The pedagogy utilises real-world problems that evolve throughout the problem-based learning activity and provide students with choice and different data sets. This new dynamic problem-based learning approach was utilised to teach…

  16. Choice, Contol and Change: Using Scientific Evidence to Promote Healthful Food and Activity Choices

    ERIC Educational Resources Information Center

    Koch, Pamela; Barton, Angela Calabrese; Whitaker, Rabi; Contento, Isobel

    2007-01-01

    Childhood obesity and its long-term health implications should be of major concern to science educators. In an effort to support teachers and youth about this growing problem, a five-unit, 19-lesson module entitled Choice, Control, and Change (C3) was developed at Teachers College Columbia University. C3 is a standards-driven and inquiry-based…

  17. Influence of the large-small split effect on strategy choice in complex subtraction.

    PubMed

    Xiang, Yan Hui; Wu, Hao; Shang, Rui Hong; Chao, Xiaomei; Ren, Ting Ting; Zheng, Li Ling; Mo, Lei

    2018-04-01

    Two main theories have been used to explain the arithmetic split effect: decision-making process theory and strategy choice theory. Using the inequality paradigm, previous studies have confirmed that individuals tend to adopt a plausibility-checking strategy and a whole-calculation strategy to solve large and small split problems in complex addition arithmetic, respectively. This supports strategy choice theory, but it is unknown whether this theory also explains performance in solving different split problems in complex subtraction arithmetic. This study used small, intermediate and large split sizes, with each split condition being further divided into problems requiring and not requiring borrowing. The reaction times (RTs) for large and intermediate splits were significantly shorter than those for small splits, while accuracy was significantly higher for large and middle splits than for small splits, reflecting no speed-accuracy trade-off. Further, RTs and accuracy differed significantly between the borrow and no-borrow conditions only for small splits. This study indicates that strategy choice theory is suitable to explain the split effect in complex subtraction arithmetic. That is, individuals tend to choose the plausibility-checking strategy or the whole-calculation strategy according to the split size. © 2016 International Union of Psychological Science.

  18. Automation of Tooling Backup and Cutter Selection for Engineering Production

    NASA Astrophysics Data System (ADS)

    Terekhov, M. V.; Averchenkov, V. I.; Reutov, A. A.; Handozhko, A. V.

    2017-01-01

    This paper reports the analysis of a tool support procedure for mechanical engineering and basic trends in the automation of this field are revealed. The system of technical-organizational measures directed at the formation, management and development of the tool stock and a high degree of technological readiness of manufacturing are described. The problems of an automated optimum cutter selection are considered. A mathematical support for a choice of cutters with through-away tips is described. A simulator for the description of combined cutters is presented. Basic criteria defining cutter choice are established. The problem of a multi-criterion fuzzy estimation of alternatives at different significance of choice criteria is solved. The criterion significance ranking at the parameter choice of cutter plates and tool supports is carried out. A set of estimations of cutter plate forms and other cutter parameters taking into account a relative significance of criteria is defined. The application of a decisive rule in the choice of an alternative required is described, which consists in the definition of the intersection of sets of alternative estimations.

  19. Using School Choice: Analyzing How Parents Access Educational Freedom. School Choice Issues in Depth

    ERIC Educational Resources Information Center

    Forster, Greg

    2005-01-01

    This report provides a summary of the process parents must go through to participate in each of the nation's school choice programs, identifying problem areas in some programs. For the first time in one place, this report collects data on participation in each of the programs in current and previous years. Data are given for the number of students…

  20. Risky Choice with Heuristics: Reply to Birnbaum (2008), Johnson, Schulte-Mecklenbeck, and Willemsen (2008), and Rieger and Wang (2008)

    ERIC Educational Resources Information Center

    Brandstatter, Eduard; Gigerenzer, Gerd; Hertwig, Ralph

    2008-01-01

    E. Brandstatter, G. Gigerenzer, and R. Hertwig (2006) showed that the priority heuristic matches or outperforms modifications of expected utility theory in predicting choice in 4 diverse problem sets. M. H. Birnbaum (2008) argued that sets exist in which the opposite is true. The authors agree--but stress that all choice strategies have regions of…

  1. Algorithm of the automated choice of points of the acupuncture for EHF-therapy

    NASA Astrophysics Data System (ADS)

    Lyapina, E. P.; Chesnokov, I. A.; Anisimov, Ya. E.; Bushuev, N. A.; Murashov, E. P.; Eliseev, Yu. Yu.; Syuzanna, H.

    2007-05-01

    Offered algorithm of the automated choice of points of the acupuncture for EHF-therapy. The recipe formed by algorithm of an automated choice of points for acupunctural actions has a recommendational character. Clinical investigations showed that application of the developed algorithm in EHF-therapy allows to normalize energetic state of the meridians and to effectively solve many problems of an organism functioning.

  2. Further examination of factors that influence preference for positive versus negative reinforcement.

    PubMed

    Kodak, Tiffany; Lerman, Dorothea C; Volkert, Valerie M; Trosclair, Nicole

    2007-01-01

    Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer during treatment (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Lalli et al., 1999). However, a number of variables may influence choice between concurrently available forms of reinforcement. An analogue for treatment situations in which positive reinforcement for compliance is in direct competition with negative reinforcement for problem behavior was used in the current study to evaluate several variables that may influence choice. Participants were 5 children who had been diagnosed with developmental disabilities and who engaged in problem behavior maintained by escape from demands. In the first phase, the effects of task preference and schedule of reinforcement on choice between a 30-s break and a high-preference food item were evaluated. The food item was preferred over the break, regardless of the preference level of the task or the reinforcement schedule, for all but 1 participant. In the second phase, the quality of the break was manipulated by combining escape with toys, attention, or both. Only 1 participant showed preference for the enriched break. In the third phase, choice of a medium- or low-preference food item versus the enriched break was evaluated. Three of 4 participants showed preference for the break over the less preferred food item. Results extend previous research by identifying some of the conditions under which individuals who engage in escape-maintained behavior will prefer a food reinforcer over the functional one.

  3. Further Examination of Factors that Influence Preference for Positive Versus Negative Reinforcement

    PubMed Central

    Kodak, Tiffany; Lerman, Dorothea C; Volkert, Valerie M; Trosclair, Nicole

    2007-01-01

    Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer during treatment (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Lalli et al., 1999). However, a number of variables may influence choice between concurrently available forms of reinforcement. An analogue for treatment situations in which positive reinforcement for compliance is in direct competition with negative reinforcement for problem behavior was used in the current study to evaluate several variables that may influence choice. Participants were 5 children who had been diagnosed with developmental disabilities and who engaged in problem behavior maintained by escape from demands. In the first phase, the effects of task preference and schedule of reinforcement on choice between a 30-s break and a high-preference food item were evaluated. The food item was preferred over the break, regardless of the preference level of the task or the reinforcement schedule, for all but 1 participant. In the second phase, the quality of the break was manipulated by combining escape with toys, attention, or both. Only 1 participant showed preference for the enriched break. In the third phase, choice of a medium- or low-preference food item versus the enriched break was evaluated. Three of 4 participants showed preference for the break over the less preferred food item. Results extend previous research by identifying some of the conditions under which individuals who engage in escape-maintained behavior will prefer a food reinforcer over the functional one. PMID:17471792

  4. Designing for Decision Making

    ERIC Educational Resources Information Center

    Jonassen, David H.

    2012-01-01

    Decision making is the most common kind of problem solving. It is also an important component skill in other more ill-structured and complex kinds of problem solving, including policy problems and design problems. There are different kinds of decisions, including choices, acceptances, evaluations, and constructions. After describing the centrality…

  5. IODC 1998 Lens Design Problem Revisited: A Strategy for Simplifying Glass Choices in an Apochromatic Design

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seppala, L G

    2000-09-15

    A glass-choice strategy, based on separately designing an achromatic lens before progressing to an apochromatic lens, simplified my approach to solving the International Optical Design Conference (IODC) 1998 lens design problem. The glasses that are needed to make the lens apochromatic are combined into triplet correctors with two ''buried'' surfaces. By applying this strategy, I reached successful solutions that used only six glasses--three glasses for the achromatic design and three additional glasses for the apochromatic design.

  6. Proceedings for the ICASE Workshop on Heterogeneous Boundary Conditions

    NASA Technical Reports Server (NTRS)

    Perkins, A. Louise; Scroggs, Jeffrey S.

    1991-01-01

    Domain Decomposition is a complex problem with many interesting aspects. The choice of decomposition can be made based on many different criteria, and the choice of interface of internal boundary conditions are numerous. The various regions under study may have different dynamical balances, indicating that different physical processes are dominating the flow in these regions. This conference was called in recognition of the need to more clearly define the nature of these complex problems. This proceedings is a collection of the presentations and the discussion groups.

  7. The Neural Basis of Risky Choice with Affective Outcomes

    PubMed Central

    Suter, Renata S.; Pachur, Thorsten; Hertwig, Ralph; Endestad, Tor; Biele, Guido

    2015-01-01

    Both normative and many descriptive theories of decision making under risk are based on the notion that outcomes are weighted by their probability, with subsequent maximization of the (subjective) expected outcome. Numerous investigations from psychology, economics, and neuroscience have produced evidence consistent with this notion. However, this research has typically investigated choices involving relatively affect-poor, monetary outcomes. We compared choice in relatively affect-poor, monetary lottery problems with choice in relatively affect-rich medical decision problems. Computational modeling of behavioral data and model-based neuroimaging analyses provide converging evidence for substantial differences in the respective decision mechanisms. Relative to affect-poor choices, affect-rich choices yielded a more strongly curved probability weighting function of cumulative prospect theory, thus signaling that the psychological impact of probabilities is strongly diminished for affect-rich outcomes. Examining task-dependent brain activation, we identified a region-by-condition interaction indicating qualitative differences of activation between affect-rich and affect-poor choices. Moreover, brain activation in regions that were more active during affect-poor choices (e.g., the supramarginal gyrus) correlated with individual trial-by-trial decision weights, indicating that these regions reflect processing of probabilities. Formal reverse inference Neurosynth meta-analyses suggested that whereas affect-poor choices seem to be based on brain mechanisms for calculative processes, affect-rich choices are driven by the representation of outcomes’ emotional value and autobiographical memories associated with them. These results provide evidence that the traditional notion of expectation maximization may not apply in the context of outcomes laden with affective responses, and that understanding the brain mechanisms of decision making requires the domain of the decision to be taken into account. PMID:25830918

  8. The neural basis of risky choice with affective outcomes.

    PubMed

    Suter, Renata S; Pachur, Thorsten; Hertwig, Ralph; Endestad, Tor; Biele, Guido

    2015-01-01

    Both normative and many descriptive theories of decision making under risk are based on the notion that outcomes are weighted by their probability, with subsequent maximization of the (subjective) expected outcome. Numerous investigations from psychology, economics, and neuroscience have produced evidence consistent with this notion. However, this research has typically investigated choices involving relatively affect-poor, monetary outcomes. We compared choice in relatively affect-poor, monetary lottery problems with choice in relatively affect-rich medical decision problems. Computational modeling of behavioral data and model-based neuroimaging analyses provide converging evidence for substantial differences in the respective decision mechanisms. Relative to affect-poor choices, affect-rich choices yielded a more strongly curved probability weighting function of cumulative prospect theory, thus signaling that the psychological impact of probabilities is strongly diminished for affect-rich outcomes. Examining task-dependent brain activation, we identified a region-by-condition interaction indicating qualitative differences of activation between affect-rich and affect-poor choices. Moreover, brain activation in regions that were more active during affect-poor choices (e.g., the supramarginal gyrus) correlated with individual trial-by-trial decision weights, indicating that these regions reflect processing of probabilities. Formal reverse inference Neurosynth meta-analyses suggested that whereas affect-poor choices seem to be based on brain mechanisms for calculative processes, affect-rich choices are driven by the representation of outcomes' emotional value and autobiographical memories associated with them. These results provide evidence that the traditional notion of expectation maximization may not apply in the context of outcomes laden with affective responses, and that understanding the brain mechanisms of decision making requires the domain of the decision to be taken into account.

  9. Can Limiting Choice Increase Social Welfare? The Elderly and Health Insurance

    PubMed Central

    Hanoch, Yaniv; Rice, Thomas

    2006-01-01

    Herbert Simon's work on bounded rationality has had little impact on health policy discourse, despite numerous supportive findings. This is particularly surprising in regard to the elderly, a group marked by a decline in higher cognitive functions. Elders' cognitive capacity to make decisions will be challenged even further with the introduction of the new Medicare prescription drug benefit program, mainly because of the many options available. At the same time, a growing body of evidence points to the perils of having too many choices. By combining research from decision science, economics, and psychology, we highlight the potential problems with the expanding health insurance choices facing the elderly and conclude with some policy suggestions to alleviate the problem. PMID:16529568

  10. Why Governments Run Schools.

    ERIC Educational Resources Information Center

    Brown, Byron W.

    1992-01-01

    Discusses problems of uncertainty and imperfect information that affect organizational choices for schools. Develops two models suggesting that schools, whether public or private, resemble each other while offering diverse curricula and outcomes. Considers the question of institutional choice by applying transaction cost economics to the options…

  11. Using Decision Trees for Estimating Mode Choice of Trips in Buca-Izmir

    NASA Astrophysics Data System (ADS)

    Oral, L. O.; Tecim, V.

    2013-05-01

    Decision makers develop transportation plans and models for providing sustainable transport systems in urban areas. Mode Choice is one of the stages in transportation modelling. Data mining techniques can discover factors affecting the mode choice. These techniques can be applied with knowledge process approach. In this study a data mining process model is applied to determine the factors affecting the mode choice with decision trees techniques by considering individual trip behaviours from household survey data collected within Izmir Transportation Master Plan. From this perspective transport mode choice problem is solved on a case in district of Buca-Izmir, Turkey with CRISP-DM knowledge process model.

  12. A Conditional Curie-Weiss Model for Stylized Multi-group Binary Choice with Social Interaction

    NASA Astrophysics Data System (ADS)

    Opoku, Alex Akwasi; Edusei, Kwame Owusu; Ansah, Richard Kwame

    2018-04-01

    This paper proposes a conditional Curie-Weiss model as a model for decision making in a stylized society made up of binary decision makers that face a particular dichotomous choice between two options. Following Brock and Durlauf (Discrete choice with social interaction I: theory, 1955), we set-up both socio-economic and statistical mechanical models for the choice problem. We point out when both the socio-economic and statistical mechanical models give rise to the same self-consistent equilibrium mean choice level(s). Phase diagram of the associated statistical mechanical model and its socio-economic implications are discussed.

  13. Monte Carlo Study Elucidates the Type 1/Type 2 Choice in Apoptotic Death Signaling in Healthy and Cancer Cells

    PubMed Central

    Raychaudhuri, Subhadip; Raychaudhuri, Somkanya C

    2013-01-01

    Apoptotic cell death is coordinated through two distinct (type 1 and type 2) intracellular signaling pathways. How the type 1/type 2 choice is made remains a central problem in the biology of apoptosis and has implications for apoptosis related diseases and therapy. We study the problem of type 1/type 2 choice in silico utilizing a kinetic Monte Carlo model of cell death signaling. Our results show that the type 1/type 2 choice is linked to deterministic versus stochastic cell death activation, elucidating a unique regulatory control of the apoptotic pathways. Consistent with previous findings, our results indicate that caspase 8 activation level is a key regulator of the choice between deterministic type 1 and stochastic type 2 pathways, irrespective of cell types. Expression levels of signaling molecules downstream also regulate the type 1/type 2 choice. A simplified model of DISC clustering elucidates the mechanism of increased active caspase 8 generation and type 1 activation in cancer cells having increased sensitivity to death receptor activation. We demonstrate that rapid deterministic activation of the type 1 pathway can selectively target such cancer cells, especially if XIAP is also inhibited; while inherent cell-to-cell variability would allow normal cells stay protected. PMID:24709706

  14. The relation of post-work ruminative thinking with eating behaviour.

    PubMed

    Cropley, Mark; Michalianou, Georgia; Pravettoni, Gabriella; Millward, Lynne J

    2012-02-01

    Inability to unwind about work during leisure time has been associated with a number of negative health outcomes. This study was concerned with a possible behavioural pathway between unwinding and disease and examined the relationship between work-related rumination and food choice. Work-related rumination is arguably a core to understanding the 'unwinding process', and food choice is a well-established indicator of nutritional health. Two hundred and sixty-eight full-time workers from a range of white-collar occupations completed a self-report measure of ruminative thinking about work and an eating behaviour questionnaire. Three types of ruminative thinking were identified by factor analysis and labelled affective rumination, problem-solving pondering and detachment. In terms of food choice, high-relative to low-affective ruminators reported eating more unhealthy foods, and low detachers reported eating less cooked meals and more processed foods compared to high detachers. Problem-solving pondering was not associated with food choice, and none of the factors were associated with healthy food choice. It was concluded that failure to unwind from work is not necessarily related to unhealthy food choices. What appears to be the crucial factor is the type of perseverative thinking that people engage in post-work. Limitations and future directions are discussed. Copyright © 2011 John Wiley & Sons, Ltd.

  15. The construct-behavior gap in behavioral decision research: A challenge beyond replicability.

    PubMed

    Regenwetter, Michel; Robinson, Maria M

    2017-10-01

    Behavioral decision research compares theoretical constructs like preferences to behavior such as observed choices. Three fairly common links from constructs to behavior are (1) to tally, across participants and decision problems, the number of choices consistent with one predicted pattern of pairwise preferences; (2) to compare what most people choose in each decision problem against a predicted preference pattern; or (3) to enumerate the decision problems in which two experimental conditions generate a 1-sided significant difference in choice frequency 'consistent' with the theory. Although simple, these theoretical links are heuristics. They are subject to well-known reasoning fallacies, most notably the fallacy of sweeping generalization and the fallacy of composition. No amount of replication can alleviate these fallacies. On the contrary, reiterating logically inconsistent theoretical reasoning over and again across studies obfuscates science. As a case in point, we consider pairwise choices among simple lotteries and the hypotheses of overweighting or underweighting of small probabilities, as well as the description-experience gap. We discuss ways to avoid reasoning fallacies in bridging the conceptual gap between hypothetical constructs, such as, for example, "overweighting" to observable pairwise choice data. Although replication is invaluable, successful replication of hard-to-interpret results is not. Behavioral decision research stands to gain much theoretical and empirical clarity by spelling out precise and formally explicit theories of how hypothetical constructs translate into observable behavior. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. Framing effects in choices between multioutcome life-expectancy lotteries.

    PubMed

    Bernstein, L M; Chapman, G B; Elstein, A S

    1999-01-01

    To explore framing or editing effects and a method to debias framing in a clinical context. Clinical scenarios using multioutcome life-expectancy lotteries of equal value required choices between two supplementary drugs that either prolonged or shortened life from the 20-year beneficial effect of a baseline drug. The effects of these supplementary drugs were presented in two conditions, using a between-subjects design. In segregated editing (n = 116) the effects were presented separately from the effects of the baseline drug. In integrated editing (n = 100), effects of supplementary and baseline drugs were combined in the lottery presentation. Each subject responded to 30 problems. To explore one method of debiasing, another 100 subjects made choices after viewing both segregated and integrated editings of 20 problems (dual framing). Statistically significant preference reversals between segregated and integrated editing of pure lotteries occurred only when one framing placed outcomes in the gain domain, and the other framing placed them in the loss domain. When both editings resulted in gain-domain outcomes only, there was no framing effect. There was a related relationship of framing-effect shifts from losses to gains in mixed-lottery-choice problems. Responses to the dual framing condition did not consistently coincide with responses to either single framing. In some situations, dual framing eliminated or lessened framing effects. The results support two components of prospect theory, coding outcomes as gains or losses from a reference point, and an s-shaped utility function (concave in gain, convex in loss domains). Presenting both alternative editings of a complex situation prior to choice more fully informs the decision maker and may help to reduce framing effects. Given the extent to which preferences shift in response to alternative presentations, it is unclear which choice represents the subject's "true preferences."

  17. Choosing experiments to accelerate collective discovery

    PubMed Central

    Rzhetsky, Andrey; Foster, Jacob G.; Foster, Ian T.

    2015-01-01

    A scientist’s choice of research problem affects his or her personal career trajectory. Scientists’ combined choices affect the direction and efficiency of scientific discovery as a whole. In this paper, we infer preferences that shape problem selection from patterns of published findings and then quantify their efficiency. We represent research problems as links between scientific entities in a knowledge network. We then build a generative model of discovery informed by qualitative research on scientific problem selection. We map salient features from this literature to key network properties: an entity’s importance corresponds to its degree centrality, and a problem’s difficulty corresponds to the network distance it spans. Drawing on millions of papers and patents published over 30 years, we use this model to infer the typical research strategy used to explore chemical relationships in biomedicine. This strategy generates conservative research choices focused on building up knowledge around important molecules. These choices become more conservative over time. The observed strategy is efficient for initial exploration of the network and supports scientific careers that require steady output, but is inefficient for science as a whole. Through supercomputer experiments on a sample of the network, we study thousands of alternatives and identify strategies much more efficient at exploring mature knowledge networks. We find that increased risk-taking and the publication of experimental failures would substantially improve the speed of discovery. We consider institutional shifts in grant making, evaluation, and publication that would help realize these efficiencies. PMID:26554009

  18. Framing effects in medical situations: distinctions of attribute, goal and risky choice frames.

    PubMed

    Peng, Jiaxi; Jiang, Yuan; Miao, Danmin; Li, Rui; Xiao, Wei

    2013-06-01

    To verify whether three different framing effects (risky choice, attribute and goal) exist in simulated medical situations and to analyse any differences. Medical decision-making problems were established, relating to medical skill evaluation, patient compliance and a selection of treatment options. All problems were described in positive and negative frame conditions. Significantly more positive evaluations were made if the doctor's medical records were described as 'of 100 patients, 70 patients became better' compared with those described as 'of 100 patients, 30 patients didn't become better'. Doctor's advice described in a negative frame resulted in significantly more decisions to comply, compared with advice described in a positive frame. Treatment options described in terms of survival rates resulted in significantly more adventurous choices compared with options described in terms of mortality rates. Decision-making reversal appeared in the risky choice and attribute frames, but not the goal frame. Framing effects were shown to exist in simulated medical situations, but there were significant differences among the three kinds of such effects.

  19. The issue of gauge choice in the Landau problem and the physics of canonical and mechanical orbital angular momenta

    NASA Astrophysics Data System (ADS)

    Wakamatsu, M.; Kitadono, Y.; Zhang, P.-M.

    2018-05-01

    One intriguing issue in the nucleon spin decomposition problem is the existence of two types of decompositions, which are representably characterized by two different orbital angular momenta (OAMs) of quarks. The one is the mechanical OAM, while the other is the so-called gauge-invariant canonical (g.i.c.) OAM, the concept of which was introduced by Chen et al. An especially delicate quantity is the g.i.c. OAM, which must be distinguished from the ordinary (gauge-variant) canonical OAM. We find that, owing to its analytically solvable nature, the famous Landau problem offers an ideal tool to understand the difference and the physical meaning of the above three OAMs, i.e. the standard canonical OAM, g.i.c. OAM, and the mechanical OAM. We analyze these three OAMs in two different formulations of the Landau problem, first in the standard (gauge-fixed) formulation and second in the gauge-invariant (but path-dependent) formulation of DeWitt. Especially interesting is the latter formalism. It is shown that the choice of path has an intimate connection with the choice of gauge, but they are not necessarily equivalent. Then, we answer the question about what is the consequence of a particular choice of path in DeWitt's formalism. This analysis also clarifies the implication of the gauge symmetry hidden in the concept of g.i.c. OAM. Finally, we show that the finding above offers a clear understanding about the uniqueness or non-uniqueness problem of the nucleon spin decomposition, which arises from the arbitrariness in the definition of the so-called physical component of the gauge field.

  20. A Spreadsheet Simulation of the Monty Hall Problem

    ERIC Educational Resources Information Center

    Patterson, Mike C.; Harmel, Bob; Friesen, Dan

    2010-01-01

    The "Monty Hall" problem or "Three Door" problem--where a person chooses one of three doors in hope of winning a valuable prize but is subsequently offered the choice of changing his or her selection--is a well known and often discussed probability problem. In this paper, the structure, history, and ultimate solution of the…

  1. MARC calculations for the second WIPP structural benchmark problem

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morgan, H.S.

    1981-05-01

    This report describes calculations made with the MARC structural finite element code for the second WIPP structural benchmark problem. Specific aspects of problem implementation such as element choice, slip line modeling, creep law implementation, and thermal-mechanical coupling are discussed in detail. Also included are the computational results specified in the benchmark problem formulation.

  2. Optimal reservoir operation policies using novel nested algorithms

    NASA Astrophysics Data System (ADS)

    Delipetrev, Blagoj; Jonoski, Andreja; Solomatine, Dimitri

    2015-04-01

    Historically, the two most widely practiced methods for optimal reservoir operation have been dynamic programming (DP) and stochastic dynamic programming (SDP). These two methods suffer from the so called "dual curse" which prevents them to be used in reasonably complex water systems. The first one is the "curse of dimensionality" that denotes an exponential growth of the computational complexity with the state - decision space dimension. The second one is the "curse of modelling" that requires an explicit model of each component of the water system to anticipate the effect of each system's transition. We address the problem of optimal reservoir operation concerning multiple objectives that are related to 1) reservoir releases to satisfy several downstream users competing for water with dynamically varying demands, 2) deviations from the target minimum and maximum reservoir water levels and 3) hydropower production that is a combination of the reservoir water level and the reservoir releases. Addressing such a problem with classical methods (DP and SDP) requires a reasonably high level of discretization of the reservoir storage volume, which in combination with the required releases discretization for meeting the demands of downstream users leads to computationally expensive formulations and causes the curse of dimensionality. We present a novel approach, named "nested" that is implemented in DP, SDP and reinforcement learning (RL) and correspondingly three new algorithms are developed named nested DP (nDP), nested SDP (nSDP) and nested RL (nRL). The nested algorithms are composed from two algorithms: 1) DP, SDP or RL and 2) nested optimization algorithm. Depending on the way we formulate the objective function related to deficits in the allocation problem in the nested optimization, two methods are implemented: 1) Simplex for linear allocation problems, and 2) quadratic Knapsack method in the case of nonlinear problems. The novel idea is to include the nested optimization algorithm into the state transition that lowers the starting problem dimension and alleviates the curse of dimensionality. The algorithms can solve multi-objective optimization problems, without significantly increasing the complexity and the computational expenses. The algorithms can handle dense and irregular variable discretization, and are coded in Java as prototype applications. The three algorithms were tested at the multipurpose reservoir Knezevo of the Zletovica hydro-system located in the Republic of Macedonia, with eight objectives, including urban water supply, agriculture, ensuring ecological flow, and generation of hydropower. Because the Zletovica hydro-system is relatively complex, the novel algorithms were pushed to their limits, demonstrating their capabilities and limitations. The nSDP and nRL derived/learned the optimal reservoir policy using 45 (1951-1995) years historical data. The nSDP and nRL optimal reservoir policy was tested on 10 (1995-2005) years historical data, and compared with nDP optimal reservoir operation in the same period. The nested algorithms and optimal reservoir operation results are analysed and explained.

  3. Therapy and Counseling

    MedlinePlus

    ... infidelity, divorce, or other relationship issues sexual problems stress and anxiety addictions and compulsions grief, loss, or bereavement anger career choice parenting or family problems phobias insomnia fertility issues chronic pain or illness domestic violence ...

  4. Health Checkup

    MedlinePlus

    Regular health exams and tests can help find problems before they start. They also can help find problems early, ... and screenings you need depends on your age, health and family history, and lifestyle choices such as ...

  5. Paramedics on the job: dynamic trunk motion assessment at the workplace.

    PubMed

    Prairie, Jérôme; Corbeil, Philippe

    2014-07-01

    Many paramedics' work accidents are related to physical aspects of the job, and the most affected body part is the low back. This study documents the trunk motion exposure of paramedics on the job. Nine paramedics were observed over 12 shifts (120 h). Trunk postures were recorded with the computer-assisted CUELA measurement system worn on the back like a knapsack. Average duration of an emergency call was 23.5 min. Sagittal trunk flexion of >40° and twisting rotation of >24° were observed in 21% and 17% of time-sampled postures. Medical care on the scene (44% of total time) involved prolonged flexed and twisted postures (∼ 10s). The highest extreme sagittal trunk flexion (63°) and twisting rotation (40°) were observed during lifting activities, which lasted 2% of the total time. Paramedics adopted trunk motions that may significantly increase the risk of low back disorders during medical care and patient-handling activities. Copyright © 2013. Published by Elsevier Ltd.

  6. Spatial interpolation of pesticide drift from hand-held knapsack sprayers used in potato production

    NASA Astrophysics Data System (ADS)

    Garcia-Santos, Glenda; Pleschberger, Martin; Scheiber, Michael; Pilz, Jürgen

    2017-04-01

    Tropical mountainous regions in developing countries are often neglected in research and policy but represent key areas to be considered if sustainable agricultural and rural development is to be promoted. One example is the lack of information of pesticide drift soil deposition, which can support pesticide risk assessment for soil, surface water, bystanders and off-target plants and fauna. This is considered a serious gap, given the evidence of pesticide-related poisoning in those regions. Empirical data of drift deposition of a pesticide surrogate, Uranine tracer, were obtained within one of the highest potato producing regions in Colombia. Based on the empirical data, different spatial interpolation techniques i.e. Thiessen, inverse distance squared weighting, co-kriging, pair-copulas and drift curves depending on distance and wind speed were tested and optimized. Results of the best performing spatial interpolation methods, suitable curves to assess mean relative drift and implications on risk assessment studies will be presented.

  7. The Thinnest Path Problem

    DTIC Science & Technology

    2016-07-22

    their corresponding transmission powers . At first glance, one may wonder whether the thinnest path problem is simply a shortest path problem with the...nature of the shortest path problem. Another aspect that complicates the problem is the choice of the transmission power at each node (within a maximum...fixed transmission power at each node (in this case, the resulting hypergraph degenerates to a standard graph), the thinnest path problem is NP

  8. Causes and types of health effects during the use of crop protection chemicals: data from a survey of over 6,300 smallholder applicators in 24 different countries.

    PubMed

    Tomenson, John A; Matthews, Graham A

    2009-08-01

    The present investigation looks in detail at the causes and types of health incidents reported by 6,300 mainly smallholder agrochemical users in 24 countries during 2005 and 2006. The investigation is based on a questionnaire survey of knowledge, attitude and practice that concentrated on the sequence of events from purchasing the pesticide to disposal. Information was also collected about health problems experienced while using agrochemicals. The survey targeted mainly smallholder knapsack spray operators who were expected to be at a highest risk of exposure. In the 12 months prior to interview, 1.2% of users reported an agrochemical-related incident that required hospital treatment, 5.8% reported an incident requiring at least trained medical treatment but not hospitalisation and 19.8% reported only a minor sign or symptom. Users who had experienced an incident involving agricultural equipment were 3.38 (95% CI 2.29-4.99) times more likely to experience an agrochemical-related health incident, but confident users who felt that their use of personal protective equipment while spraying was best practice were 0.60 (95% CI 0.44-0.84) times less likely to experience such an incident. Over 80% of product-related incidents were caused by insecticides and the incidence rate per spraying time for incidents linked to insecticides was significantly higher than that for fungicides or herbicides. Headache/dizziness and nausea/vomiting, often smell related, were the most common symptoms reported by users who listed agrochemical products that had caused them health problems (52 and 38% of product mentions, respectively). In most countries, the incidence of serious health effects was low; however, there was a high incidence of minor signs and symptoms in a few countries, especially in Africa. A disproportionate number of incidents occurred during insecticide use relative to the time that they were sprayed. Failure to exercise caution as indicated by whether users had incidents involving agricultural equipment or livestock, and lack of confidence in their practices were the most important predictors of agrochemical-related incidents.

  9. Choice of Variables and Preconditioning for Time Dependent Problems

    NASA Technical Reports Server (NTRS)

    Turkel, Eli; Vatsa, Verr N.

    2003-01-01

    We consider the use of low speed preconditioning for time dependent problems. These are solved using a dual time step approach. We consider the effect of this dual time step on the parameter of the low speed preconditioning. In addition, we compare the use of two sets of variables, conservation and primitive variables, to solve the system. We show the effect of these choices on both the convergence to a steady state and the accuracy of the numerical solutions for low Mach number steady state and time dependent flows.

  10. Teaching Emotional Intelligence: Making Informed Choices. K-College.

    ERIC Educational Resources Information Center

    Lewkowicz, Adina Bloom

    Teachers can help lessen their students' frustrations, make classroom time more productive, and prevent behavioral and learning problems by providing students with information and skills with which to make informed, positive, and independent choices regarding their emotional, social, physical, and mental well-being. This resource for teachers…

  11. Matching and Conditioned Reinforcement Rate

    ERIC Educational Resources Information Center

    Shahan, Timothy A.; Podlesnik, Christopher A.; Jimenez-Gomez, Corina

    2006-01-01

    Attempts to examine the effects of variations in relative conditioned reinforcement rate on choice have been confounded by changes in rates of primary reinforcement or changes in the value of the conditioned reinforcer. To avoid these problems, this experiment used concurrent observing responses to examine sensitivity of choice to relative…

  12. Group differences in adult simple arithmetic: good retrievers, not-so-good retrievers, and perfectionists.

    PubMed

    Hecht, Steven A

    2006-01-01

    We used the choice/no-choice methodology in two experiments to examine patterns of strategy selection and execution in groups of undergraduates. Comparisons between choice and no-choice trials revealed three groups. Some participants good retrievers) were consistently able to use retrieval to solve almost all arithmetic problems. Other participants (perfectionists) successfully used retrieval substantially less often in choice-allowed trials than when strategy choices were prohibited. Not-so-good retrievers retrieved correct answers less often than the other participants in both the choice-allowed and no-choice conditions. No group differences emerged with respect to time needed to search and access answers from long-term memory; however, not-so-good retrievers were consistently slower than the other subgroups at executing fact-retrieval processes that are peripheral to memory search and access. Theoretical models of simple arithmetic, such as the Strategy Choice and Discovery Simulation (Shrager & Siegler, 1998), should be updated to include the existence of both perfectionist and not-so-good retriever adults.

  13. Summertime, and the Choosin' Ain't Easy: An Ice Cream Counting Problem.

    ERIC Educational Resources Information Center

    Kreith, Kurt

    1992-01-01

    Utilizes the problem of determining the number of different ice cream cones and cups that can be made from a choice of 31 flavors to investigate the concepts of combinations and permutations. Provides a set of six related problems with their answers. (MDH)

  14. Modeling Incorrect Responses to Multiple-Choice Items with Multilinear Formula Score Theory.

    ERIC Educational Resources Information Center

    Drasgow, Fritz; And Others

    This paper addresses the information revealed in incorrect option selection on multiple choice items. Multilinear Formula Scoring (MFS), a theory providing methods for solving psychological measurement problems of long standing, is first used to estimate option characteristic curves for the Armed Services Vocational Aptitude Battery Arithmetic…

  15. Erik Erikson's Theory of Psychosocial Development and Vocational Behavior

    ERIC Educational Resources Information Center

    Munley, Patrick H.

    1975-01-01

    Stage resolution attitudes, derived from the first six stage crises outlined by Erikson, were explored as variables influencing problems in vocational choice and vocational maturity. Findings indicated students who made adjusted vocational choices and developed mature career attitudes had also been more successful resolving the first six…

  16. An Analysis of Student Choices in Medical Ethical Dilemmas.

    ERIC Educational Resources Information Center

    Woloshin, Phyllis Lerman

    This report describes a study undertaken to assess student choices in medical ethical dilemmas. Medical ethical dilemmas are interpreted to include problems such as abortion, euthanasia, sterilization, experimentation on humans, allocation of scarce medical resources, and physician and health personnel training. The major purpose of the study was…

  17. Questioning Collectives and Agencies: A Commentary on Curricular Choices

    ERIC Educational Resources Information Center

    Arnold, Jenny

    2015-01-01

    This commentary explores theoretical alternatives for viewing the problem identified by Volny Fages and Virginie Albe in their article entitled Social issues in nanoscience and nanotechnology Master's degrees: The socio-political stakes of curricular choices. An approach to social research is suggested that would render visible the associations…

  18. How to Assess Student Performance in Science: Going beyond Multiple-Choice Tests. Third Edition

    ERIC Educational Resources Information Center

    Butler, Susan M.; McColskey, Wendy; O'Sullivan, Rita

    2005-01-01

    Educational systems promote student growth in a variety of dimensions. Basic content knowledge can be effectively assessed with multiple-choice and completion tests. However educational reforms have become more concerned with higher-order cognitive dimensions (problem-solving, creativity), social dimensions (communication skills, ability to work…

  19. Project Choice: Lessons Learned in Dropout Prevention.

    ERIC Educational Resources Information Center

    Sims, Abby

    In Project Choice, Ewing Marion Kauffman, through his Kauffman Foundation, offered a college education to inner city youth in selected schools in Kansas City, Kansas, and Kansas City, Missouri. In exchange students and parents agreed among other things that students would avoid disciplinary problems in school and the community, maintain…

  20. Restricted Liberty, Parental Choice and Homeschooling

    ERIC Educational Resources Information Center

    Merry, Michael S.; Karsten, Sjoerd

    2010-01-01

    In this paper the authors carefully study the problem of liberty as it applies to school choice, and whether there ought to be restricted liberty in the case of homeschooling. They examine three prominent concerns that might be brought against homeschooling, viz., that it aggravates social inequality, worsens societal conflict and works against…

  1. Reasoning and choice in the Monty Hall Dilemma (MHD): implications for improving Bayesian reasoning

    PubMed Central

    Tubau, Elisabet; Aguilar-Lleyda, David; Johnson, Eric D.

    2015-01-01

    The Monty Hall Dilemma (MHD) is a two-step decision problem involving counterintuitive conditional probabilities. The first choice is made among three equally probable options, whereas the second choice takes place after the elimination of one of the non-selected options which does not hide the prize. Differing from most Bayesian problems, statistical information in the MHD has to be inferred, either by learning outcome probabilities or by reasoning from the presented sequence of events. This often leads to suboptimal decisions and erroneous probability judgments. Specifically, decision makers commonly develop a wrong intuition that final probabilities are equally distributed, together with a preference for their first choice. Several studies have shown that repeated practice enhances sensitivity to the different reward probabilities, but does not facilitate correct Bayesian reasoning. However, modest improvements in probability judgments have been observed after guided explanations. To explain these dissociations, the present review focuses on two types of causes producing the observed biases: Emotional-based choice biases and cognitive limitations in understanding probabilistic information. Among the latter, we identify a crucial cause for the universal difficulty in overcoming the equiprobability illusion: Incomplete representation of prior and conditional probabilities. We conclude that repeated practice and/or high incentives can be effective for overcoming choice biases, but promoting an adequate partitioning of possibilities seems to be necessary for overcoming cognitive illusions and improving Bayesian reasoning. PMID:25873906

  2. A random utility model of delay discounting and its application to people with externalizing psychopathology.

    PubMed

    Dai, Junyi; Gunn, Rachel L; Gerst, Kyle R; Busemeyer, Jerome R; Finn, Peter R

    2016-10-01

    Previous studies have demonstrated that working memory capacity plays a central role in delay discounting in people with externalizing psychopathology. These studies used a hyperbolic discounting model, and its single parameter-a measure of delay discounting-was estimated using the standard method of searching for indifference points between intertemporal options. However, there are several problems with this approach. First, the deterministic perspective on delay discounting underlying the indifference point method might be inappropriate. Second, the estimation procedure using the R2 measure often leads to poor model fit. Third, when parameters are estimated using indifference points only, much of the information collected in a delay discounting decision task is wasted. To overcome these problems, this article proposes a random utility model of delay discounting. The proposed model has 2 parameters, 1 for delay discounting and 1 for choice variability. It was fit to choice data obtained from a recently published data set using both maximum-likelihood and Bayesian parameter estimation. As in previous studies, the delay discounting parameter was significantly associated with both externalizing problems and working memory capacity. Furthermore, choice variability was also found to be significantly associated with both variables. This finding suggests that randomness in decisions may be a mechanism by which externalizing problems and low working memory capacity are associated with poor decision making. The random utility model thus has the advantage of disclosing the role of choice variability, which had been masked by the traditional deterministic model. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  3. Behavioural social choice: a status report.

    PubMed

    Regenwetter, Michel; Grofman, Bernard; Popova, Anna; Messner, William; Davis-Stober, Clintin P; Cavagnaro, Daniel R

    2009-03-27

    Behavioural social choice has been proposed as a social choice parallel to seminal developments in other decision sciences, such as behavioural decision theory, behavioural economics, behavioural finance and behavioural game theory. Behavioural paradigms compare how rational actors should make certain types of decisions with how real decision makers behave empirically. We highlight that important theoretical predictions in social choice theory change dramatically under even minute violations of standard assumptions. Empirical data violate those critical assumptions. We argue that the nature of preference distributions in electorates is ultimately an empirical question, which social choice theory has often neglected. We also emphasize important insights for research on decision making by individuals. When researchers aggregate individual choice behaviour in laboratory experiments to report summary statistics, they are implicitly applying social choice rules. Thus, they should be aware of the potential for aggregation paradoxes. We hypothesize that such problems may substantially mar the conclusions of a number of (sometimes seminal) papers in behavioural decision research.

  4. A review of the application and contribution of discrete choice experiments to inform human resources policy interventions

    PubMed Central

    Lagarde, Mylene; Blaauw, Duane

    2009-01-01

    Although the factors influencing the shortage and maldistribution of health workers have been well-documented by cross-sectional surveys, there is less evidence on the relative determinants of health workers' job choices, or on the effects of policies designed to address these human resources problems. Recently, a few studies have adopted an innovative approach to studying the determinants of health workers' job preferences. In the absence of longitudinal datasets to analyse the decisions that health workers have actually made, authors have drawn on methods from marketing research and transport economics and used Discrete Choice Experiments to analyse stated preferences of health care providers for different job characteristics. We carried out a literature review of studies using discrete choice experiments to investigate human resources issues related to health workers, both in developed and developing countries. Several economic and health systems bibliographic databases were used, and contacts were made with practitioners in the field to identify published and grey literature. Ten studies were found that used discrete choice experiments to investigate the job preferences of health care providers. The use of discrete choice experiments techniques enabled researchers to determine the relative importance of different factors influencing health workers' choices. The studies showed that non-pecuniary incentives are significant determinants, sometimes more powerful than financial ones. The identified studies also emphasized the importance of investigating the preferences of different subgroups of health workers. Discrete choice experiments are a valuable tool for informing decision-makers on how to design strategies to address human resources problems. As they are relatively quick and cheap survey instruments, discrete choice experiments present various advantages for informing policies in developing countries, where longitudinal labour market data are seldom available. Yet they are complex research instruments requiring expertise in a number of different areas. Therefore it is essential that researchers also understand the potential limitations of discrete choice experiment methods. PMID:19630965

  5. How to Design a Spectrometer.

    PubMed

    Scheeline, Alexander

    2017-10-01

    Designing a spectrometer requires knowledge of the problem to be solved, the molecules whose properties will contribute to a solution of that problem and skill in many subfields of science and engineering. A seemingly simple problem, design of an ultraviolet, visible, and near-infrared spectrometer, is used to show the reasoning behind the trade-offs in instrument design. Rather than reporting a fully optimized instrument, the Yin and Yang of design choices, leading to decisions about financial cost, materials choice, resolution, throughput, aperture, and layout are described. To limit scope, aspects such as grating blaze, electronics design, and light sources are not presented. The review illustrates the mixture of mathematical rigor, rule of thumb, esthetics, and availability of components that contribute to the art of spectrometer design.

  6. How did you guess? Or, what do multiple-choice questions measure?

    PubMed

    Cox, K R

    1976-06-05

    Multiple-choice questions classified as requiring problem-solving skills have been interpreted as measuring problem-solving skills within students, with the implicit hypothesis that questions needing an increasingly complex intellectual process should present increasing difficulty to the student. This hypothesis was tested in a 150-question paper taken by 721 students in seven Australian medical schools. No correlation was observed between difficulty and assigned process. Consequently, the question-answering process was explored with a group of final-year students. Anecdotal recall by students gave heavy weight to knowledge rather than problem solving in answering these questions. Assignment of the 150 questions to the classification by three teachers and six students showed their congruence to be a little above random probability.

  7. The August Krogh principle applies to plants

    NASA Technical Reports Server (NTRS)

    Wayne, R.; Staves, M. P.

    1996-01-01

    The Krogh principle refers to the use of a large number of animals to study the large number of physiological problems, rather than limiting study to a particular organism for all problems. There may be organisms that are more suited to study of a particular problem than others. This same principle applies to plants. The authors are concerned with the recent trend in plant biology of using Arabidopsis thaliana as the "organism of choice." Arabidopsis is an excellent organism for molecular genetic research, but other plants are superior models for other research areas of plant biology. The authors present examples of the successful use of the Krogh principle in plant cell biology research, emphasizing the particular characteristics of the selected research organisms that make them the appropriate choice.

  8. An Introduction to Multi-player, Multi-choice Quantum Games: Quantum Minority Games & Kolkata Restaurant Problems

    NASA Astrophysics Data System (ADS)

    Sharif, Puya; Heydari, Hoshang

    We give a self contained introduction to a few quantum game protocols, starting with the quantum version of the two-player two-choice game of Prisoners dilemma, followed by an n-player generalization trough the quantum minority games, and finishing with a contribution towards an n-player m-choice generalization with a quantum version of a three-player Kolkata restaurant problem. We have omitted some technical details accompanying these protocols, and instead laid the focus on presenting some general aspects of the field as a whole. This review contains an introduction to the formalism of quantum information theory, as well as to important game theoretical concepts, and is aimed to work as a review suiting economists and game theorists with limited knowledge of quantum physics as well as to physicists with limited knowledge of game theory.

  9. Using Data Analysis Problems in a Large General Microbiology Course.

    ERIC Educational Resources Information Center

    Deutch, Charles E.

    1997-01-01

    Argues that data analysis problems can be used successfully in large introductory microbiology courses, even when exams consist entirely of multiple-choice questions and out-of-class contact with the instructor is limited. Discusses course organization, problem structure, student performance and response, advantages of using data analysis…

  10. Students' and Teachers' Conceptual Metaphors for Mathematical Problem Solving

    ERIC Educational Resources Information Center

    Yee, Sean P.

    2017-01-01

    Metaphors are regularly used by mathematics teachers to relate difficult or complex concepts in classrooms. A complex topic of concern in mathematics education, and most STEM-based education classes, is problem solving. This study identified how students and teachers contextualize mathematical problem solving through their choice of metaphors.…

  11. Framing Effects: Dynamics and Task Domains

    PubMed

    Wang

    1996-11-01

    The author examines the mechanisms and dynamics of framing effects in risky choices across three distinct task domains (i.e., life-death, public property, and personal money). The choice outcomes of the problems presented in each of the three task domains had a binary structure of a sure thing vs a gamble of equal expected value; the outcomes differed in their framing conditions and the expected values, raging from 6000, 600, 60, to 6, numerically. It was hypothesized that subjects would become more risk seeking, if the sure outcome was below their aspiration level (the minimum requirement). As predicted, more subjects preferred the gamble when facing the life-death choice problems than facing the counterpart problems presented in the other two task domains. Subjects' risk preference varied categorically along the group size dimension in the life-death domain but changed more linearly over the expected value dimension in the monetary domain. Framing effects were observed in 7 of 13 pairs of problems, showing a positive frame-risk aversion and negative frame-risk seeking relationship. In addition, two types of framing effects were theoretically defined and empirically identified. A bidirectional framing effect involves a reversal in risk preference, and occurs when a decision maker's risk preference is ambiguous or weak. Four bidirectional effects were observed; in each case a majority of subjects preferred the sure outcome under a positive frame but the gamble under a negative frame. In contrast, a unidirectional framing effect refers to a preference shift due to the framing of choice outcomes: A majority of subjects preferred one choice outcome (either the sure thing or the gamble) under both framing conditions, with positive frame augmented the preference for the sure thing and negative frame augmented the preference for the gamble. These findings revealed some dynamic regularities of framing effects and posed implications for developing predictive and testable models of human decision making.

  12. [The framing effect: medical implications].

    PubMed

    Mazzocco, Ketti; Cherubini, Paolo; Rumiati, Rino

    2005-01-01

    Over the last 20 years, many studies explored how the way information is presented modifies choices. This sort of effect, referred to as "framing effects", typically consists of the inversion of choices when presenting structurally identical decision problems in different ways. It is a common assumption that physicians are unaffected (or less affected) by the surface description of a decision problem, because they are formally trained in medical decision making. However, several studies showed that framing effects occur even in the medical field. The complexity and variability of these effects are remarkable, making it necessary to distinguish among different framing effects, depending on whether the effect is obtained by modifying adjectives (attribute framing), goals of a behavior (goal framing), or the probability of an outcome (risky choice framing). A further reason for the high variability of the framing effects seems to be the domain of the decision problem, with different effects occurring in prevention decisions, disease-detection decisions, and treatment decisions. The present work reviews the studies on framing effects, in order to summarize them and clarify their possible role in medical decision making.

  13. Problems of Younger Workers in the USSR

    ERIC Educational Resources Information Center

    Kotlyar, Alexander

    1974-01-01

    Young workers, persons from sixteen to thirty years old, have problems relating to occupational choice, vocational guidance, vocational training and other educational opportunities, job satisfaction, and housing, complicating their search for an occupational and social identity. (AG)

  14. The Framing of Decisions and the Psychology of Choice.

    ERIC Educational Resources Information Center

    Tversky, Amos; Kahneman, Daniel

    1981-01-01

    Presents evidence that the psychological principles that govern the perception of decision problems and evaluation of probabilities and outcomes produce predictable shifts of preference when the same problem is framed in different ways. (Author/SK)

  15. Computational fluency and strategy choice predict individual and cross-national differences in complex arithmetic.

    PubMed

    Vasilyeva, Marina; Laski, Elida V; Shen, Chen

    2015-10-01

    The present study tested the hypothesis that children's fluency with basic number facts and knowledge of computational strategies, derived from early arithmetic experience, predicts their performance on complex arithmetic problems. First-grade students from United States and Taiwan (N = 152, mean age: 7.3 years) were presented with problems that differed in difficulty: single-, mixed-, and double-digit addition. Children's strategy use varied as a function of problem difficulty, consistent with Siegler's theory of strategy choice. The use of decomposition strategy interacted with computational fluency in predicting the accuracy of double-digit addition. Further, the frequency of decomposition and computational fluency fully mediated cross-national differences in accuracy on these complex arithmetic problems. The results indicate the importance of both fluency with basic number facts and the decomposition strategy for later arithmetic performance. (c) 2015 APA, all rights reserved).

  16. Choice, Preferences, and Constraints: Evidence from Public School Applications in Denver

    ERIC Educational Resources Information Center

    Denice, Patrick; Gross, Betheny

    2016-01-01

    Does ''choosing a home'' still matter for ''choosing a school,'' despite implementation of school choice policies designed to weaken this link? Prior research shows how the presence of such policies does little to solve the problems of stratification and segregation associated with residentially based enrollment systems, since families differ…

  17. Learning-Method Choices and Personal Characteristics in Solving a Physical Education Problem

    ERIC Educational Resources Information Center

    Vincent-Morin, Madeleine; Lafont, Lucile

    2005-01-01

    The goal of this study was to identify the relationships between the learning choices made by pupils and their personal characteristics, including cognitive style (field dependence--independence), a motivational variable (feeling of self-efficacy), and a cognitive variable (task representation). The participants were 64 twelve-year-old sixth…

  18. Violent Society, Violent Schools: It's a Question of Choice.

    ERIC Educational Resources Information Center

    Morgenstern, Robert E.

    A contemporary theory of behavior is that faulty patterns of thinking divide the criminal from the noncriminal. The causation of school violence is children choosing to be violent; and the problem of school violence is acceptance of their choice. Short-term control measures are adherence to systematic school rules, use of technology, security…

  19. Cheating on Multiple-Choice Exams: Monitoring, Assessment, and an Optional Assignment

    ERIC Educational Resources Information Center

    Nath, Leda; Lovaglia, Michael

    2009-01-01

    Academic dishonesty is unethical. Exam cheating is viewed as more serious than most other forms (Pincus and Schmelkin 2003). The authors review the general cheating problem, introduce a program to conservatively identify likely cheaters on multiple-choice exams, and offer a procedure for handling likely cheaters. Feedback from students who confess…

  20. Turning to Teaching: Gender and Career Choice

    ERIC Educational Resources Information Center

    Raggl, Andrea; Troman, Geoff

    2008-01-01

    As the largest public sector institution in the United Kingdom, education is a key site for studying the context of "choice" and changes in the identities of professional workers in contemporary society. Recruitment and retention problems in education have led to the creation of new routes into teaching to attract career changers from…

  1. Behavioral Assessment of Impulsivity: A Comparison of Children with and without Attention Deficit Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Neef, Nancy A.; Marckel, Julie; Ferreri, Summer J.; Bicard, David F.; Endo, Sayaka; Aman, Michael G.; Miller, Kelly M.; Jung, Sunhwa; Nist, Lindsay; Armstrong, Nancy

    2005-01-01

    We conducted a brief computer-based assessment involving choices of concurrently presented arithmetic problems associated with competing reinforcer dimensions to assess impulsivity (choices controlled primarily by reinforcer immediacy) as well as the relative influence of other dimensions (reinforcer rate, quality, and response effort), with 58…

  2. How IRT Can Solve Problems of Ipsative Data in Forced-Choice Questionnaires

    ERIC Educational Resources Information Center

    Brown, Anna; Maydeu-Olivares, Alberto

    2013-01-01

    In multidimensional forced-choice (MFC) questionnaires, items measuring different attributes are presented in blocks, and participants have to rank order the items within each block (fully or partially). Such comparative formats can reduce the impact of numerous response biases often affecting single-stimulus items (aka rating or Likert scales).…

  3. Representation Use and Strategy Choice in Physics Problem Solving

    ERIC Educational Resources Information Center

    De Cock, Mieke

    2012-01-01

    In this paper, we examine student success on three variants of a test item given in different representational formats (verbal, pictorial, and graphical), with an isomorphic problem statement. We confirm results from recent papers where it is mentioned that physics students' problem-solving competence can vary with representational format and that…

  4. An Introduction to Multilinear Formula Score Theory. Measurement Series 84-4.

    ERIC Educational Resources Information Center

    Levine, Michael V.

    Formula score theory (FST) associates each multiple choice test with a linear operator and expresses all of the real functions of item response theory as linear combinations of the operator's eigenfunctions. Hard measurement problems can then often be reformulated as easier, standard mathematical problems. For example, the problem of estimating…

  5. Skills and Dispositions for Creative Problem Solving during the Artmaking Process

    ERIC Educational Resources Information Center

    Pitri, Eliza

    2013-01-01

    In this article, Eliza Pitri states, "when allowed to make and explain their own choices, students develop invaluable creative problem-solving skills." Opportunities for such critical thinking abound in the art classroom. The importance of identifying how skills and dispositions related to creative problem solving are expressed in a…

  6. Problems Involved in the Choice and Use of Materials in Airplane Construction

    NASA Technical Reports Server (NTRS)

    Brenner, Paul

    1932-01-01

    The present state of the problem of materials in airplane construction is studied on the basis of data giving the principal characteristics of different materials and showing how they affect the form of airplane parts.

  7. Processes in arithmetic strategy selection: a fMRI study.

    PubMed

    Taillan, Julien; Ardiale, Eléonore; Anton, Jean-Luc; Nazarian, Bruno; Félician, Olivier; Lemaire, Patrick

    2015-01-01

    This neuroimaging (functional magnetic resonance imaging) study investigated neural correlates of strategy selection. Young adults performed an arithmetic task in two different conditions. In both conditions, participants had to provide estimates of two-digit multiplication problems like 54 × 78. In the choice condition, participants had to select the better of two available rounding strategies, rounding-up (RU) strategy (i.e., doing 60 × 80 = 4,800) or rounding-down (RD) strategy (i.e., doing 50 × 70 = 3,500 to estimate product of 54 × 78). In the no-choice condition, participants did not have to select strategy on each problem but were told which strategy to use; they executed RU and RD strategies each on a series of problems. Participants also had a control task (i.e., providing correct products of multiplication problems like 40 × 50). Brain activations and performance were analyzed as a function of these conditions. Participants were able to frequently choose the better strategy in the choice condition; they were also slower when they executed the difficult RU than the easier RD. Neuroimaging data showed greater brain activations in right anterior cingulate cortex (ACC), dorso-lateral prefrontal cortex (DLPFC), and angular gyrus (ANG), when selecting (relative to executing) the better strategy on each problem. Moreover, RU was associated with more parietal cortex activation than RD. These results suggest an important role of fronto-parietal network in strategy selection and have important implications for our further understanding and modeling cognitive processes underlying strategy selection.

  8. Processes in arithmetic strategy selection: a fMRI study

    PubMed Central

    Taillan, Julien; Ardiale, Eléonore; Anton, Jean-Luc; Nazarian, Bruno; Félician, Olivier; Lemaire, Patrick

    2015-01-01

    This neuroimaging (functional magnetic resonance imaging) study investigated neural correlates of strategy selection. Young adults performed an arithmetic task in two different conditions. In both conditions, participants had to provide estimates of two-digit multiplication problems like 54 × 78. In the choice condition, participants had to select the better of two available rounding strategies, rounding-up (RU) strategy (i.e., doing 60 × 80 = 4,800) or rounding-down (RD) strategy (i.e., doing 50 × 70 = 3,500 to estimate product of 54 × 78). In the no-choice condition, participants did not have to select strategy on each problem but were told which strategy to use; they executed RU and RD strategies each on a series of problems. Participants also had a control task (i.e., providing correct products of multiplication problems like 40 × 50). Brain activations and performance were analyzed as a function of these conditions. Participants were able to frequently choose the better strategy in the choice condition; they were also slower when they executed the difficult RU than the easier RD. Neuroimaging data showed greater brain activations in right anterior cingulate cortex (ACC), dorso-lateral prefrontal cortex (DLPFC), and angular gyrus (ANG), when selecting (relative to executing) the better strategy on each problem. Moreover, RU was associated with more parietal cortex activation than RD. These results suggest an important role of fronto-parietal network in strategy selection and have important implications for our further understanding and modeling cognitive processes underlying strategy selection. PMID:25698995

  9. Textbook Forum: Equilibrium Constants of Chemical Reactions Involving Condensed Phases: Pressure Dependence and Choice of Standard State.

    ERIC Educational Resources Information Center

    Perlmutter-Hayman, Berta

    1984-01-01

    Problems of equilibria in condensed phases (particularly those involving solutes in dilute solutions) are encountered by students in their laboratory work; the thermodynamics of these equilibria is neglected in many textbooks. Therefore, several aspects of this topic are explored, focusing on pressure dependence and choice of standard state. (JN)

  10. How Generalizable Is Your Experiment? An Index for Comparing Samples and Populations

    ERIC Educational Resources Information Center

    Tipton, Elizabeth

    2013-01-01

    Recent research on the design of social experiments has highlighted the effects of different design choices on research findings. Since experiments rarely collect their samples using random selection, in order to address these external validity problems and design choices, recent research has focused on two areas. The first area is on methods for…

  11. Making Consumer Choices. Secondary Learning Guide 6. Project Connect. Linking Self-Family-Work.

    ERIC Educational Resources Information Center

    Emily Hall Tremaine Foundation, Inc., Hartford, CT.

    This competency-based secondary learning guide on making consumer choices is part of a series that are adaptations of guides developed for adult consumer and homemaking education programs. The guides provide students with experiences that help them learn to do the following: make decisions; use creative approaches to solve problems; establish…

  12. Implementation of School Choice Policy: Interpretation and Response by Parents of Students with Special Educational Needs.

    ERIC Educational Resources Information Center

    Bagley, Carl; Woods, Philip A.; Woods, Glenys

    2001-01-01

    Provides empirically based insights into preferences, perceptions, and responses of parents of students with special education needs to the 1990s restructured school system in England. Uses analyses of quantitative/qualitative data generated by a large-scale research study on school choice. Reveals depth and range of problems encountered by these…

  13. Private Schools and Parental Choice: Dubious Assumptions, Frail Claims, and Excessive Hyperbole. Occasional Paper.

    ERIC Educational Resources Information Center

    Corwin, Ronald G.

    The preoccupation with choice between public and private schools offered under voucher programs obscures the greater problem of a lack of variety in the present educational system. If providing a greater variety of school structures and improving the educational system is the objective, competition between the public and private sectors will not…

  14. The Display of Multiple Choice Question Bank on Microfilm

    ERIC Educational Resources Information Center

    Stevens, J. M.; Harris, F. T. C.

    1977-01-01

    An automated question bank maintained by the Department of Research and Services in Education at the Middlesex Hospital Medical School provides a printed copy of each of 25,000 multiple choice questions (95 percent relating to the whole spectrum of the medical curriculum). Problems with this procedure led to experimental work storing the data on…

  15. High Pressure Reform: Examining Urban Schools' Response to Multiple School Choice Policies

    ERIC Educational Resources Information Center

    Holme, Jennifer Jellison; Carkhum, Rian; Rangel, Virginia Snodgrass

    2013-01-01

    Over the past several decades, policymakers have sought to address the problem of school failure by exposing traditional public schools to competitive market forces. In this analysis, we examine how two traditional public schools in a "high pressure/high choice" urban school cluster in Texas responded to a number of overlapping choice…

  16. Patterns of problem-solving in children's literacy and arithmetic.

    PubMed

    Farrington-Flint, Lee; Vanuxem-Cotterill, Sophie; Stiller, James

    2009-11-01

    Patterns of problem-solving among 5-to-7 year-olds' were examined on a range of literacy (reading and spelling) and arithmetic-based (addition and subtraction) problem-solving tasks using verbal self-reports to monitor strategy choice. The results showed higher levels of variability in the children's strategy choice across Years I and 2 on the arithmetic (addition and subtraction) than literacy-based tasks (reading and spelling). However, across all four tasks, the children showed a tendency to move from less sophisticated procedural-based strategies, which included phonological strategies for reading and spelling and counting-all and finger modellingfor addition and subtraction, to more efficient retrieval methods from Years I to 2. Distinct patterns in children's problem-solving skill were identified on the literacy and arithmetic tasks using two separate cluster analyses. There was a strong association between these two profiles showing that those children with more advanced problem-solving skills on the arithmetic tasks also showed more advanced profiles on the literacy tasks. The results highlight how different-aged children show flexibility in their use of problem-solving strategies across literacy and arithmetical contexts and reinforce the importance of studying variations in children's problem-solving skill across different educational contexts.

  17. How Do They Solve It? An Insight into the Learner's Approach to the Mechanism of Physics Problem Solving

    ERIC Educational Resources Information Center

    Hegde, Balasubrahmanya; Meera, B. N.

    2012-01-01

    A perceived difficulty is associated with physics problem solving from a learner's viewpoint, arising out of a multitude of reasons. In this paper, we have examined the microstructure of students' thought processes during physics problem solving by combining the analysis of responses to multiple-choice questions and semistructured student…

  18. Who Is He? Children with ASD and ADHD Take the Listener into Account in Their Production of Ambiguous Pronouns

    PubMed Central

    Kuijper, Sanne J. M.; Hartman, Catharina A.; Hendriks, Petra

    2015-01-01

    During conversation, speakers constantly make choices about how specific they wish to be in their use of referring expressions. In the present study we investigate whether speakers take the listener into account or whether they base their referential choices solely on their own representation of the discourse. We do this by examining the cognitive mechanisms that underlie the choice of referring expression at different discourse moments. Furthermore, we provide insights into how children with Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD) use referring expressions and whether their use differs from that of typically developing (TD) children. Children between 6 and 12 years old (ASD: n=46; ADHD: n=37; TD: n=38) were tested on their production of referring expressions and on Theory of Mind, response inhibition and working memory. We found support for the view that speakers take the listener into account when choosing a referring expression: Theory of Mind was related to referential choice only at those moments when speakers could not solely base their choice on their own discourse representation to be understood. Working memory appeared to be involved in keeping track of the different referents in the discourse. Furthermore, we found that TD children as well as children with ASD and children with ADHD took the listener into account in their choice of referring expression. In addition, children with ADHD were less specific than TD children in contexts with more than one referent. The previously observed problems with referential choice in children with ASD may lie in difficulties in keeping track of longer and more complex discourses, rather than in problems with taking into account the listener. PMID:26147200

  19. A responsible method of making healthcare choices.

    PubMed

    Scandlen, Greg

    2002-01-01

    The essential problem in healthcare has never been fee-for-service. The problem is third-party payment that inevitably leads to excessive demand for services. Third-party payers will always try to limit the use and cost of services to reduce their exposure. The big question facing us in the next 10 years is who decides what gets paid for and what doesn't. Will it be employers, insurers, the government? Or it will it be consumers? Many employers have concluded that Americans are perfectly capable of expressing their preferences and choices in healthcare. But they need to understand that resources are limited and trade-offs are required.

  20. Decision-making Strategies and Performance among Seniors1

    PubMed Central

    Besedeš, Tibor; Deck, Cary; Sarangi, Sudipta; Shor, Mikhael

    2011-01-01

    Using paper and pencil experiments administered in senior centers, we examine decision-making performance in multi-attribute decision problems. We differentiate the effects of declining cognitive performance and changing cognitive process on decision-making performance of seniors as they age. We find a significant decline in performance with age due to reduced reliance on common heuristics and increased decision-making randomness among our oldest subjects. However, we find that increasing the number of options in a decision problem increases the number of heuristics brought to the task. This challenges the choice overload view that people give up when confronted with too much choice. PMID:22408282

  1. Motion and force control of multiple robotic manipulators

    NASA Technical Reports Server (NTRS)

    Wen, John T.; Kreutz-Delgado, Kenneth

    1992-01-01

    This paper addresses the motion and force control problem of multiple robot arms manipulating a cooperatively held object. A general control paradigm is introduced which decouples the motion and force control problems. For motion control, different control strategies are constructed based on the variables used as the control input in the controller design. There are three natural choices; acceleration of a generalized coordinate, arm tip force vectors, and the joint torques. The first two choices require full model information but produce simple models for the control design problem. The last choice results in a class of relatively model independent control laws by exploiting the Hamiltonian structure of the open loop system. The motion control only determines the joint torque to within a manifold, due to the multiple-arm kinematic constraint. To resolve the nonuniqueness of the joint torques, two methods are introduced. If the arm and object models are available, an optimization can be performed to best allocate the desired and effector control force to the joint actuators. The other possibility is to control the internal force about some set point. It is shown that effective force regulation can be achieved even if little model information is available.

  2. CHAPTER 10: CURRENT TECHNICAL PROBLEMS IN EMERGY ANALYSIS

    EPA Science Inventory

    Technical problems related to the determination of the emergy base for self-organization in environmental systems are considered in this paper. The comparability of emergy analysis results depends on emergy analysts making similar choices in determining the emergy base for a part...

  3. Human Prenatal Effects: Methodological Problems and Some Suggested Solutions

    ERIC Educational Resources Information Center

    Copans, Stuart A.

    1974-01-01

    Briefly reviews the relevant literature on human prenatal effects, describes some of the possible designs for such studies; and discusses some of the methodological problem areas: sample choice, measurement of prenatal variables, monitoring of labor and delivery, and neonatal assessment. (CS)

  4. A survey exploring self-reported indoor and outdoor footwear habits, foot problems and fall status in people with stroke and Parkinson's.

    PubMed

    Bowen, Catherine; Ashburn, Ann; Cole, Mark; Donovan-Hall, Margaret; Burnett, Malcolm; Robison, Judy; Mamode, Louis; Pickering, Ruth; Bader, Dan; Kunkel, Dorit

    Ill-fitting shoes have been implicated as a risk factor for falls but research to date has focused on people with arthritis, diabetes and the general older population; little is known about people with neurological conditions. This survey for people with stroke and Parkinson's explored people's choice of indoor and outdoor footwear, foot problems and fall history. Following ethical approval, 1000 anonymous postal questionnaires were distributed to health professionals, leads of Parkinson's UK groups and stroke clubs in the wider Southampton area, UK. These collaborators handed out survey packs to people with a confirmed diagnosis of stroke or Parkinson's. Three hundred and sixty three completed surveys were returned (218 from people with Parkinson's and 145 from people with stroke). Most respondents wore slippers indoors and walking shoes outdoors and considered comfort and fit the most important factors when buying footwear. Foot problems were reported by 43 % (95 % confidence intervals 36 to 52 %; stroke) and 53 % (95 % confidence interval 46 to 59 %; Parkinson's) of respondents; over 50 % had never accessed foot care support. Fifty percent of all respondents reported falls. In comparison to non-fallers, a greater proportion of fallers reported foot problems (57 %), with greater proportions reporting problems impacting on balance and influencing choice of footwear ( p  < 0.01) in comparison to non-fallers in each case. Forty-seven percent of fallers with foot problems had not accessed foot care support. Many people with stroke and Parkinson's wear slippers indoors. A high percentage of these individuals reported both foot problems and falls impacting on footwear habits and choice of footwear; however many did not receive foot care support. These findings highlight that further exploration of footwear and foot problems in these populations is warranted to provide evidence based advice on safe and appropriate footwear to support rehabilitation and fall prevention.

  5. Formal language constrained path problems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barrett, C.; Jacob, R.; Marathe, M.

    1997-07-08

    In many path finding problems arising in practice, certain patterns of edge/vertex labels in the labeled graph being traversed are allowed/preferred, while others are disallowed. Motivated by such applications as intermodal transportation planning, the authors investigate the complexity of finding feasible paths in a labeled network, where the mode choice for each traveler is specified by a formal language. The main contributions of this paper include the following: (1) the authors show that the problem of finding a shortest path between a source and destination for a traveler whose mode choice is specified as a context free language is solvablemore » efficiently in polynomial time, when the mode choice is specified as a regular language they provide algorithms with improved space and time bounds; (2) in contrast, they show that the problem of finding simple paths between a source and a given destination is NP-hard, even when restricted to very simple regular expressions and/or very simple graphs; (3) for the class of treewidth bounded graphs, they show that (i) the problem of finding a regular language constrained simple path between source and a destination is solvable in polynomial time and (ii) the extension to finding context free language constrained simple paths is NP-complete. Several extensions of these results are presented in the context of finding shortest paths with additional constraints. These results significantly extend the results in [MW95]. As a corollary of the results, they obtain a polynomial time algorithm for the BEST k-SIMILAR PATH problem studied in [SJB97]. The previous best algorithm was given by [SJB97] and takes exponential time in the worst case.« less

  6. Forced Choices: Role Play and the Problem of Disappearing Syntax

    ERIC Educational Resources Information Center

    Kellogg, David

    2014-01-01

    We begin with the observation that some Korean elementary school children in English class, confined to a single situation and even a single language exponent in a role play, appear to produce far more coherent dialogue than the previous week when they were allowed completely free choices in language. We note that at the same time as their…

  7. Adult Career Counseling Using Possible Selves--A Quasi-Experimental Field Study in Naturalistic Settings

    ERIC Educational Resources Information Center

    Plimmer, Geoff

    2012-01-01

    This study examined the effectiveness of an adult career development program designed to reflect the diversity and demands of career choices, the low level of comfort many have with career choices, and the limited resources available to resolve complex adult career problems. A possible selves process was used, delivered through a blend of computer…

  8. Drivin' Trucks, Huntin' Bucks, and Reading Aristotle?: The Rural Student's College Choice Dilemma

    ERIC Educational Resources Information Center

    Strawn, Rachel Mayes

    2014-01-01

    Even though rural students make up a fifth of the population of all American students, they do not attend college in numbers equivalent to urban and suburban students. The rural student faces influences related to college choice that differ from those of suburban and urban students. These influences, which could be considered problems or barriers,…

  9. Retraining the European Workforce: How Technologies Can Help. Training Discussion Paper No. 95.

    ERIC Educational Resources Information Center

    Araujo e Oliveira, Joao Batista; Lau, Alex

    The discussion of long- versus short-term effects is usually absent when it comes to the choice of training technology. Short-term effects become the major criteria for the choice: training resolves a concrete problem. An important reason for thinking about long-term effects of training and training strategies is the ultimate objective of training…

  10. Redundancy allocation problem for k-out-of- n systems with a choice of redundancy strategies

    NASA Astrophysics Data System (ADS)

    Aghaei, Mahsa; Zeinal Hamadani, Ali; Abouei Ardakan, Mostafa

    2017-03-01

    To increase the reliability of a specific system, using redundant components is a common method which is called redundancy allocation problem (RAP). Some of the RAP studies have focused on k-out-of- n systems. However, all of these studies assumed predetermined active or standby strategies for each subsystem. In this paper, for the first time, we propose a k-out-of- n system with a choice of redundancy strategies. Therefore, a k-out-of- n series-parallel system is considered when the redundancy strategy can be chosen for each subsystem. In other words, in the proposed model, the redundancy strategy is considered as an additional decision variable and an exact method based on integer programming is used to obtain the optimal solution of the problem. As the optimization of RAP belongs to the NP-hard class of problems, a modified version of genetic algorithm (GA) is also developed. The exact method and the proposed GA are implemented on a well-known test problem and the results demonstrate the efficiency of the new approach compared with the previous studies.

  11. Blueberry Pancakes, Please.

    ERIC Educational Resources Information Center

    Leana, Frank C.

    1994-01-01

    Describes three case vignettes of college freshmen who are unhappy with their choice of schools early in their freshman years. Considers problems in dormitory living, academic pressures, and interpersonal problems. Discusses change in the campus environment in recent decades and the need for adult involvement in campus life. (NB)

  12. Learning to Write about Mathematics

    ERIC Educational Resources Information Center

    Parker, Renee; Breyfogle, M. Lynn

    2011-01-01

    Beginning in third grade, Pennsylvania students are required to take the Pennsylvania State Standardized Assessment (PSSA), which presents multiple-choice mathematics questions and open-ended mathematics problems. Consistent with the Communication Standard of the National Council of Teachers of Mathematics, while solving the open-ended problems,…

  13. Wavelet-sparsity based regularization over time in the inverse problem of electrocardiography.

    PubMed

    Cluitmans, Matthijs J M; Karel, Joël M H; Bonizzi, Pietro; Volders, Paul G A; Westra, Ronald L; Peeters, Ralf L M

    2013-01-01

    Noninvasive, detailed assessment of electrical cardiac activity at the level of the heart surface has the potential to revolutionize diagnostics and therapy of cardiac pathologies. Due to the requirement of noninvasiveness, body-surface potentials are measured and have to be projected back to the heart surface, yielding an ill-posed inverse problem. Ill-posedness ensures that there are non-unique solutions to this problem, resulting in a problem of choice. In the current paper, it is proposed to restrict this choice by requiring that the time series of reconstructed heart-surface potentials is sparse in the wavelet domain. A local search technique is introduced that pursues a sparse solution, using an orthogonal wavelet transform. Epicardial potentials reconstructed from this method are compared to those from existing methods, and validated with actual intracardiac recordings. The new technique improves the reconstructions in terms of smoothness and recovers physiologically meaningful details. Additionally, reconstruction of activation timing seems to be improved when pursuing sparsity of the reconstructed signals in the wavelet domain.

  14. Simple and complex mental subtraction: strategy choice and speed-of-processing differences in younger and older adults.

    PubMed

    Geary, D C; Frensch, P A; Wiley, J G

    1993-06-01

    Thirty-six younger adults (10 male, 26 female; ages 18 to 38 years) and 36 older adults (14 male, 22 female; ages 61 to 80 years) completed simple and complex paper-and-pencil subtraction tests and solved a series of simple and complex computer-presented subtraction problems. For the computer task, strategies and solution times were recorded on a trial-by-trial basis. Older Ss used a developmentally more mature mix of problem-solving strategies to solve both simple and complex subtraction problems. Analyses of component scores derived from the solution times suggest that the older Ss are slower at number encoding and number production but faster at executing the borrow procedure. In contrast, groups did not appear to differ in the speed of subtraction fact retrieval. Results from a computational simulation are consistent with the interpretation that older adults' advantage for strategy choices and for the speed of executing the borrow procedure might result from more practice solving subtraction problems.

  15. Microcomputer data acquisition and control.

    PubMed

    East, T D

    1986-01-01

    In medicine and biology there are many tasks that involve routine well defined procedures. These tasks are ideal candidates for computerized data acquisition and control. As the performance of microcomputers rapidly increases and cost continues to go down the temptation to automate the laboratory becomes great. To the novice computer user the choices of hardware and software are overwhelming and sadly most of the computer sales persons are not at all familiar with real-time applications. If you want to bill your patients you have hundreds of packaged systems to choose from; however, if you want to do real-time data acquisition the choices are very limited and confusing. The purpose of this chapter is to provide the novice computer user with the basics needed to set up a real-time data acquisition system with the common microcomputers. This chapter will cover the following issues necessary to establish a real time data acquisition and control system: Analysis of the research problem: Definition of the problem; Description of data and sampling requirements; Cost/benefit analysis. Choice of Microcomputer hardware and software: Choice of microprocessor and bus structure; Choice of operating system; Choice of layered software. Digital Data Acquisition: Parallel Data Transmission; Serial Data Transmission; Hardware and software available. Analog Data Acquisition: Description of amplitude and frequency characteristics of the input signals; Sampling theorem; Specification of the analog to digital converter; Hardware and software available; Interface to the microcomputer. Microcomputer Control: Analog output; Digital output; Closed-Loop Control. Microcomputer data acquisition and control in the 21st Century--What is in the future? High speed digital medical equipment networks; Medical decision making and artificial intelligence.

  16. Good choices, great future: an applied theatre prevention program to reduce alcohol-related risky behaviours during Schoolies.

    PubMed

    Quek, Lake-Hui; White, Angela; Low, Christine; Brown, Judith; Dalton, Nigel; Dow, Debbie; Connor, Jason P

    2012-11-01

    The contextual and temporal factors of post-school celebratory events ('Schoolies') place young people at elevated risk of excessive drinking compared with other social occasions. This study investigates the impact of an applied theatre prevention program 'Choices' in reducing the risk of drinking and other risk behaviours during Schoolies celebrations. Choices was delivered in the last term of Year 12 across 28 North Queensland schools. A total of 352 school leavers (43.1% male, mean age = 17.14 years) completed a questionnaire at Whitsunday Schoolies, Queensland, Australia on 23-24 November 2010. Nearly 49% of respondents had attended Choices. The survey included measures of alcohol use, illicit drug use and associated problems during Schoolies and a month prior to Schoolies. After controlling for gender and pre-Schoolies drinking, school leavers who attended Choices were significantly less likely to report illicit drug use (OR = 0.51, P < 0.05) and problem behaviours (OR = 0.40, P < 0.01) than those who did not attend Choices. There was, however, no intervention effect in risky drinking (i.e. drank on 5 or more days, typical amount five or more standard drink and binge drank on 3 or more days) at Schoolies (OR = 0.92, P = 0.80). Delivery of a youth-specific applied theatre prevention program employing a harm minimisation framework may be effective in reducing high-risk behaviours associated with alcohol consumption at celebratory events, even if young people expect to engage in excessive alcohol consumption. © 2012 Australasian Professional Society on Alcohol and other Drugs.

  17. What Students Choose to Do and Have to Say about Use of Multiple Representations in College Algebra

    ERIC Educational Resources Information Center

    Herman, Marlena

    2007-01-01

    This report summarizes findings on strategies chosen by students (n=38) when solving algebra problems related to various functions with the freedom to use a TI-83 graphing calculator, influences on student problem-solving strategy choices, student ability to approach algebra problems with use of multiple representations, and student beliefs on how…

  18. Food Selectivity, Mealtime Behavior Problems, Spousal Stress, and Family Food Choices in Children with and without Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Curtin, C.; Hubbard, K.; Anderson, S. E.; Mick, E.; Must, A.; Bandini, L. G.

    2015-01-01

    Mealtime behavior problems and family stress occur frequently among families of children with autism spectrum disorder (ASD). However, it is unknown whether food selectivity is an associated factor. The associations of high food selectivity with mealtime behavior problems, spousal stress, and influence on family members were assessed among 53…

  19. Reliability and Validity of a Procedure to Measure Diagnostic Reasoning and Problem-Solving Skills Taught in Predoctoral Orthodontic Education.

    ERIC Educational Resources Information Center

    Albanese, Mark A.; Jacobs, Richard M.

    1990-01-01

    The reliability and validity of a procedure to measure diagnostic-reasoning and problem-solving skills taught in predoctoral orthodontic education were studied using 68 second year dental students. The procedure includes stimulus material and 33 multiple-choice items. It is a feasible way of assessing problem-solving skills in dentistry education…

  20. Assignment Choice, Effort, and Assignment Completion: Does Work Ethic Predict Those Who Choose Higher-Effort Assignments?

    ERIC Educational Resources Information Center

    Parkhurst, John T.; Fleisher, Matthew S.; Skinner, Christopher H.; Woehr, David J.; Hawthorn-Embree, Meredith L.

    2011-01-01

    After completing the Multidimensional Work-Ethic Profile (MWEP), 98 college students were given a 20-problem math computation assignment and instructed to stop working on the assignment after completing 10 problems. Next, they were allowed to choose to finish either the partially completed assignment that had 10 problems remaining or a new…

  1. Joint Labor-Management Decision Making: Choices, Outcomes, and Problems.

    ERIC Educational Resources Information Center

    Cooke, William N.

    1991-01-01

    Reviews the literature and analyses of the joint problem-solving strategies that have emerged during the 1980s and are used by management and labor to improve company performance, employee welfare, and labor-management relations. Includes a 58-item bibliography and 32 additional references. (JOW)

  2. Soft Technologies, Hard Choices. Worldwatch Paper 21.

    ERIC Educational Resources Information Center

    Norman, Colin

    The infusion of technology into society has created social and environmental problems as well as benefits. Four concerns linked with technology are discussed in this paper: rising unemployment, growing social inequalities, dwindling oil and gas reserves, and potential long-term ecological problems. Indiscriminate transfer of modern labor-saving…

  3. Helping students learn effective problem solving strategies by reflecting with peers

    NASA Astrophysics Data System (ADS)

    Mason, Andrew; Singh, Chandralekha

    2010-07-01

    We study how introductory physics students engage in reflection with peers about problem solving. The recitations for an introductory physics course with 200 students were broken into a "peer reflection" (PR) group and a traditional group. Each week in recitation, small teams of students in the PR group reflected on selected problems from the homework and discussed why the solutions of some students employed better problem solving strategies than others. The graduate and undergraduate teaching assistants in the PR recitations provided guidance and coaching to help students learn effective problem solving heuristics. In the traditional group recitations students could ask the graduate TA questions about the homework before they took a weekly quiz. The traditional group recitation quiz questions were similar to the homework questions selected for peer reflection in the PR group recitations. As one measure of the impact of this intervention, we investigated how likely students were to draw diagrams to help with problem solving on the final exam with only multiple-choice questions. We found that the PR group drew diagrams on more problems than the traditional group even when there was no explicit reward for doing so. Also, students who drew more diagrams for the multiple-choice questions outperformed those who did not, regardless of which group they were a member.

  4. Identifying instructional tasks that occasion problem behaviors and assessing the effects of student versus teacher choice among these tasks.

    PubMed

    Vaughn, B J; Horner, R H

    1997-01-01

    Levels of problem behavior were assessed when 4 students with severe disabilities received instruction on preferred versus nonpreferred tasks and when tasks of each type were chosen by the teacher rather than by the student. In Phase 1, interview and direct observation assessments were conducted to identify relative preferences for academic tasks. In Phase 2, the effects of these lower preference and higher preference tasks on the rate of problem behavior were evaluated using a multielement design. The results showed that lower preference tasks were associated with higher rates of problem behaviors and that students, when given a choice, consistently selected the tasks that had been identified through interview and direct observation as higher preference. In Phase 3, we assessed whether allowing the students to choose between pairs of lower preference tasks or between pairs of higher preference tasks reduced problem behavior relative to a condition in which the teacher selected the same tasks. For 2 of 4 students, the rates of problem behavior were lower when students (rather than the teacher) selected the lower preference activity. Higher preference tasks for 3 students were associated with relatively low rates of problem behavior regardless of whether the student or the teacher selected the task.

  5. Issues or Identity? Cognitive Foundations of Voter Choice

    PubMed Central

    Jenke, Libby; Huettel, Scott A.

    2016-01-01

    Voter choice is one of the most important problems in political science. The most common models assume that voting is a rational choice based on policy positions (e.g., key issues) and non-policy information (e.g., social identity, personality). Though such models explain macroscopic features of elections, they also reveal important anomalies that have been resistant to explanation. We argue for a new approach that builds upon recent research in cognitive science and neuroscience; specifically, we contend that policy positions and social identities do not combine in merely an additive manner, but compete to determine voter preferences. This model not only explains several key anomalies in voter choice, but also suggests new directions for research in both political science and cognitive science. PMID:27769726

  6. A Subjective Rational Choice

    NASA Astrophysics Data System (ADS)

    Vinogradov, G. P.

    2017-01-01

    The problem of constructing a choice model of an agent with endogenous purposes of evolution is under debate. It is demonstrated that its solution requires the development of well-known methods of decision-making while taking into account the relation of action mode motivation to an agent’s ambition to implement subjectively understood interests and the environment state. The latter is submitted for consideration as a purposeful state situation model that exists only in the mind of an agent. It is the situation that is a basis for getting an insight into the agent’s ideas on the possible selected action mode results. The agent’s ambition to build his confidence in the feasibility of the action mode and the possibility of achieving the desired state requires him to use the procedures of forming an idea model based on the measured values of environment state. This leads to the gaming approach for the choice problem and its solution can be obtained on a set of trade-off alternatives.

  7. The Possible Application of Socioeconomic Careers and Path Analysis Concepts to the Study of Factors Relevant to Physicians' Choice of Practice Location.

    ERIC Educational Resources Information Center

    Grimes, Walter F.

    In response to the current shortage of rural physicians and the difficulties encountered in studying this problem, this paper attempts to apply a specific multivariate technique (path analysis) and the socioeconomic careers model of Featherman and others to the study of the physician's choice of practice location. The socioeconomic careers model…

  8. Using Distractor-Driven Standards-Based Multiple-Choice Assessments and Rasch Modeling to Investigate Hierarchies of Chemistry Misconceptions and Detect Structural Problems with Individual Items

    ERIC Educational Resources Information Center

    Herrmann-Abell, Cari F.; DeBoer, George E.

    2011-01-01

    Distractor-driven multiple-choice assessment items and Rasch modeling were used as diagnostic tools to investigate students' understanding of middle school chemistry ideas. Ninety-one items were developed according to a procedure that ensured content alignment to the targeted standards and construct validity. The items were administered to 13360…

  9. Higher Education Marketing Strategies Based on Factors Impacting the Enrollees' Choice of a University and an Academic Program

    ERIC Educational Resources Information Center

    Kalimullin, Aydar M.; Dobrotvorskaya, Svetlana G.

    2016-01-01

    The relevance of studying the stated problem is due to the fact that for increasing the efficiency of higher education marketing it is necessary to take into account several factors, namely, factors that impact the choice of a university and an academic program by enrollees, as well as socio-psychological characteristics of the latter, while…

  10. Alternative-Specific and Case-Specific Factors Involved in the Decisions of Islamic School Teachers Affecting Teacher Retention: A Discrete Choice Experiment

    ERIC Educational Resources Information Center

    Abd-El-Hafez, Alaa Karem

    2015-01-01

    Teacher retention is a concern in all educational sectors in America. It is of special importance to Islamic schools, which tend to lack the resources necessary in recruiting and training new teachers. This dissertation addressed this problem in full-time Islamic schools in New York State by conducting a discrete choice experiment, which reflects…

  11. Experiments to Generate New Data about School Choice: Commentary on "Defining Continuous Improvement and Cost Minimization Possibilities through School Choice Experiments" and Merrifield's Reply

    ERIC Educational Resources Information Center

    Berg, Nathan; Merrifield, John

    2009-01-01

    Benefiting from new data provided by experimental economists, behavioral economics is now moving beyond empirical tests of standard behavioral assumptions to the problem of designing improved institutions that are tuned to fit real-world behavior. It is therefore worthwhile to consider the potential for new experiments to advance school choice…

  12. Scramjet Nozzles

    DTIC Science & Technology

    2010-09-01

    and y, the axial and radial coordinates respectively. Point c lies somewhere within the mesh generated by the initial expansion (the kernel). All that...and the surface will be subjected to high heat loads restricting the choice of suitable materials. Material choice has direct implications for...Some legacy trajectory codes might not be able to deal with anything other than axial forces from engines, reflecting the class of problem they were

  13. Course Modality Choice and Student Performance in Business Statistics Courses in Post Secondary Institutions

    ERIC Educational Resources Information Center

    Radners, Richard Harry, Jr.

    2011-01-01

    Limited research has been conducted on the role of course modality choice (face-to-face [FTF] or online [OL]) on course grades. At the study site, an independent college, the research problem was the lack of research on the proportions of undergraduate students who completed a statistics course as part of their academic program, in either OL or…

  14. Path integral measure, constraints and ghosts for massive gravitons with a cosmological constant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Metaxas, Dimitrios

    2009-12-15

    For massive gravity in a de Sitter background one encounters problems of stability when the curvature is larger than the graviton mass. I analyze this situation from the path integral point of view and show that it is related to the conformal factor problem of Euclidean quantum (massless) gravity. When a constraint for massive gravity is incorporated and the proper treatment of the path integral measure is taken into account one finds that, for particular choices of the DeWitt metric on the space of metrics (in fact, the same choices as in the massless case), one obtains the opposite boundmore » on the graviton mass.« less

  15. Long-range analysis of density fitting in extended systems

    NASA Astrophysics Data System (ADS)

    Varga, Scarontefan

    Density fitting scheme is analyzed for the Coulomb problem in extended systems from the correctness of long-range behavior point of view. We show that for the correct cancellation of divergent long-range Coulomb terms it is crucial for the density fitting scheme to reproduce the overlap matrix exactly. It is demonstrated that from all possible fitting metric choices the Coulomb metric is the only one which inherently preserves the overlap matrix for infinite systems with translational periodicity. Moreover, we show that by a small additional effort any non-Coulomb metric fit can be made overlap-preserving as well. The problem is analyzed for both ordinary and Poisson basis set choices.

  16. Separate neural mechanisms underlie choices and strategic preferences in risky decision making.

    PubMed

    Venkatraman, Vinod; Payne, John W; Bettman, James R; Luce, Mary Frances; Huettel, Scott A

    2009-05-28

    Adaptive decision making in real-world contexts often relies on strategic simplifications of decision problems. Yet, the neural mechanisms that shape these strategies and their implementation remain largely unknown. Using an economic decision-making task, we dissociate brain regions that predict specific choices from those predicting an individual's preferred strategy. Choices that maximized gains or minimized losses were predicted by functional magnetic resonance imaging activation in ventromedial prefrontal cortex or anterior insula, respectively. However, choices that followed a simplifying strategy (i.e., attending to overall probability of winning) were associated with activation in parietal and lateral prefrontal cortices. Dorsomedial prefrontal cortex, through differential functional connectivity with parietal and insular cortex, predicted individual variability in strategic preferences. Finally, we demonstrate that robust decision strategies follow from neural sensitivity to rewards. We conclude that decision making reflects more than compensatory interaction of choice-related regions; in addition, specific brain systems potentiate choices depending on strategies, traits, and context.

  17. Separate neural mechanisms underlie choices and strategic preferences in risky decision making

    PubMed Central

    Venkatraman, Vinod; Payne, John W.; Bettman, James R.; Luce, Mary Frances; Huettel, Scott A.

    2011-01-01

    Adaptive decision making in real-world contexts often relies on strategic simplifications of decision problems. Yet, the neural mechanisms that shape these strategies and their implementation remain largely unknown. Using a novel economic decision-making task, we dissociate brain regions that predict specific choices from those predicting an individual’s preferred strategy. Choices that maximized gains or minimized losses were predicted by fMRI activation in ventromedial prefrontal cortex or anterior insula, respectively. However, choices that followed a simplifying strategy (i.e., attending to overall probability of winning) were associated with activation in parietal and lateral prefrontal cortices. Dorsomedial prefrontal cortex, through differential functional connectivity with parietal and insular cortex, predicted individual variability in strategic preferences. Finally, we demonstrate that robust decision strategies follow from neural sensitivity to rewards. We conclude that decision making reflects more than compensatory interaction of choice-related regions; in addition, specific brain systems potentiate choices depending upon strategies, traits, and context. PMID:19477159

  18. Optimal assessment of multiple cues.

    PubMed Central

    Fawcett, Tim W; Johnstone, Rufus A

    2003-01-01

    In a wide range of contexts from mate choice to foraging, animals are required to discriminate between alternative options on the basis of multiple cues. How should they best assess such complex multicomponent stimuli? Here, we construct a model to investigate this problem, focusing on a simple case where a 'chooser' faces a discrimination task involving two cues. These cues vary in their accuracy and in how costly they are to assess. As an example, we consider a mate-choice situation where females choose between males of differing quality. Our model predicts the following: (i) females should become less choosy as the cost of finding new males increases; (ii) females should prioritize cues differently depending on how choosy they are; (iii) females may sometimes prioritize less accurate cues; and (iv) which cues are most important depends on the abundance of desirable mates. These predictions are testable in mate-choice experiments where the costs of choice can be manipulated. Our findings are applicable to other discrimination tasks besides mate choice, for example a predator's choice between palatable and unpalatable prey, or an altruist's choice between kin and non-kin. PMID:12908986

  19. Role of Information in Consumer Selection of Health Plans

    PubMed Central

    Sainfort, François; Booske, Bridget C.

    1996-01-01

    Considerable efforts are underway in the public and private sectors to increase the amount of information available to consumers when making health plan choices. The objective of this study was to examine the role of information in consumer health plan decisionmaking. A computer system was developed which provides different plan descriptions with the option of accessing varying types and levels of information. The system tracked the information search processes and recorded the hypothetical plan choices of 202 subjects. Results are reported showing the relationship between information and problem perception, preference structure, choice of plan, and attitude towards the decision. PMID:10165036

  20. The overconstraint of response time models: rethinking the scaling problem.

    PubMed

    Donkin, Chris; Brown, Scott D; Heathcote, Andrew

    2009-12-01

    Theories of choice response time (RT) provide insight into the psychological underpinnings of simple decisions. Evidence accumulation (or sequential sampling) models are the most successful theories of choice RT. These models all have the same "scaling" property--that a subset of their parameters can be multiplied by the same amount without changing their predictions. This property means that a single parameter must be fixed to allow the estimation of the remaining parameters. In the present article, we show that the traditional solution to this problem has overconstrained these models, unnecessarily restricting their ability to account for data and making implicit--and therefore unexamined--psychological assumptions. We show that versions of these models that address the scaling problem in a minimal way can provide a better description of data than can their overconstrained counterparts, even when increased model complexity is taken into account.

  1. Learning in occupational transitions: a study of the process following job loss.

    PubMed

    Hallqvist, Anders; Hydén, Lars-Christer

    2012-01-01

    This article examines how workers supported by outplacement services engage with an occupational transition through problem solving and learning. The participants were 23 mid-life redundant white collar workers with at least eight years in their sector, organization or occupation. The selected interviewees either participated in training to broaden their professional competence or did not make any such 'expansive' efforts. The study was based on narrative interviews, which enabled a detailed cross case examination of individuals' actions and choices and how the process unfolds over time. The results showed that people treat their job loss as a practical problem to be solved using various strategies. This problem-solving process is structured, with people passing similar crossroads defining particular challenges and opportunities giving people limited sets of choices. The results point to the significance of creativity and learning in occupational transitions.

  2. The forced-choice paradigm and the perception of facial expressions of emotion.

    PubMed

    Frank, M G; Stennett, J

    2001-01-01

    The view that certain facial expressions of emotion are universally agreed on has been challenged by studies showing that the forced-choice paradigm may have artificially forced agreement. This article addressed this methodological criticism by offering participants the opportunity to select a none of these terms are correct option from a list of emotion labels in a modified forced-choice paradigm. The results show that agreement on the emotion label for particular facial expressions is still greater than chance, that artifactual agreement on incorrect emotion labels is obviated, that participants select the none option when asked to judge a novel expression, and that adding 4 more emotion labels does not change the pattern of agreement reported in universality studies. Although the original forced-choice format may have been prone to artifactual agreement, the modified forced-choice format appears to remedy that problem.

  3. ChoiceKey: a real-time speech recognition program for psychology experiments with a small response set.

    PubMed

    Donkin, Christopher; Brown, Scott D; Heathcote, Andrew

    2009-02-01

    Psychological experiments often collect choice responses using buttonpresses. However, spoken responses are useful in many cases-for example, when working with special clinical populations, or when a paradigm demands vocalization, or when accurate response time measurements are desired. In these cases, spoken responses are typically collected using a voice key, which usually involves manual coding by experimenters in a tedious and error-prone manner. We describe ChoiceKey, an open-source speech recognition package for MATLAB. It can be optimized by training for small response sets and different speakers. We show ChoiceKey to be reliable with minimal training for most participants in experiments with two different responses. Problems presented by individual differences, and occasional atypical responses, are examined, and extensions to larger response sets are explored. The ChoiceKey source files and instructions may be downloaded as supplemental materials for this article from brm.psychonomic-journals.org/content/supplemental.

  4. A Linear Algebraic Approach to Teaching Interpolation

    ERIC Educational Resources Information Center

    Tassa, Tamir

    2007-01-01

    A novel approach for teaching interpolation in the introductory course in numerical analysis is presented. The interpolation problem is viewed as a problem in linear algebra, whence the various forms of interpolating polynomial are seen as different choices of a basis to the subspace of polynomials of the corresponding degree. This approach…

  5. Evaluation of Complex Human Performance: The Promise of Computer-Based Simulation

    ERIC Educational Resources Information Center

    Newsom, Robert S.; And Others

    1978-01-01

    For the training and placement of professional workers, multiple-choice instruments are the norm for wide-scale measurement and evaluation efforts. These instruments contain fundamental problems. Computer-based management simulations may provide solutions to these problems, appear scoreable and reliable, offer increased validity, and are better…

  6. Refusing To Play the Blame Game.

    ERIC Educational Resources Information Center

    Dowd, JoAnne

    1997-01-01

    Frustrated by her ninth graders' misbehavior with a substitute teacher, a high school English teacher shelved her recriminations and engaged miscreants in a problem-solving exercise examining the incident. Establishing a protocol to talk about problems openly, without fear of retribution, made a big difference. Boys admitted to some poor choices;…

  7. Lexical Frames and Reported Speech

    ERIC Educational Resources Information Center

    Williams, Howard

    2004-01-01

    This paper addresses a problem of lexical choice that arises for ESL/EFL learners in the writing of research papers, critiques, interview reports, or any other sort of discourse that requires source attribution. The problem falls naturally into two parts. One part concerns the general lack of linguistic resources typically available (for various…

  8. New York Community Environment Study Questionnaire.

    ERIC Educational Resources Information Center

    Glaser, Daniel; Snow, Mary

    This questionnaire assesses neighborhood drug problem concern, drug use practices, knowledge of drugs and agencies dealing with drugs, and views on drug education in persons aged 13 or older. The questionnaire has 31 items (multiple-choice or free response), most with several parts. The items deal with demographic and personal data, problems in…

  9. The Relationship between Instructional Variables and Problem Behavior: A Review.

    ERIC Educational Resources Information Center

    Munk, Dennis D.; Repp, Alan C.

    1994-01-01

    This paper reviews studies that have used instructional variables as nonaversive interventions for problem behaviors of individuals with severe disabilities. These include student choice of task, task variation, pace of instruction, interspersal of high probability tasks, partial versus whole task training, decreasing task difficulty, and a…

  10. How to Develop Teachers' Mathematical Molding Teaching Skills

    ERIC Educational Resources Information Center

    Mrayyan, Salwa

    2016-01-01

    This study aimed at developing some of the mathematical modelling skills necessary for the student teachers in mathematics education College. Modeling involves making genuine choices, modeling problems have many possible justifiable answers, modeling problems matter to the end-user who needs to understand something or make a decision. Modeling…

  11. Adolescent Health: A Generation at Risk.

    ERIC Educational Resources Information Center

    Hechinger, Fred M.

    1994-01-01

    A 3-day conference brought together health and education experts to explore responses to adolescent health problems and to suggest ways to implement the recommendations put forward in "Fateful Choices: Healthy Youth for the 21st Century," by Fred M. Hechinger. Conference participants identified a number of adolescent health problems and the areas…

  12. Students' Conceptual Difficulties in Quantum Mechanics: Potential Well Problems

    ERIC Educational Resources Information Center

    Ozcan, Ozgur; Didis, Nilufer; Tasar, Mehmet Fatih

    2009-01-01

    In this study, students' conceptual difficulties about some basic concepts in quantum mechanics like one-dimensional potential well problems and probability density of tunneling particles were identified. For this aim, a multiple choice instrument named Quantum Mechanics Conceptual Test has been developed by one of the researchers of this study…

  13. Environmental Problems, Causes, and Solutions: An Open Question

    ERIC Educational Resources Information Center

    Negev, Maya; Garb, Yaakov; Biller, Roni; Sagy, Gonen; Tal, Alon

    2010-01-01

    In a national evaluation of environmental literacy in Israel, (Negev, Sagy, Garb, Salzberg, & Tal, 2008), the authors included both multiple choice questions and open questions. In this article the authors describe the qualitative analysis of the answers to an open question regarding a local environmental problem. Most participants specified…

  14. Examining Parents’ Preferences for Group and Individual Parent Training For Children with ADHD Symptoms

    PubMed Central

    Wymbs, Frances A.; Cunningham, Charles E.; Chen, Yvonne; Rimas, Heather M.; Deal, Ken; Waschbusch, Daniel A.; Pelham, William E.

    2015-01-01

    Parent training (PT) programs have been found to reduce some behavioral impairment associated with children’s attention deficit hyperactivity disorder (ADHD) as well as improve parenting competence, but poor uptake and participation by parents are formidable barriers that affect service effectiveness. We used a discrete choice experiment (DCE) to examine how parent preferences for treatment format (i.e. group versus individual) might influence their participation in PT. Participants were 445 parents seeking mental health services for children with elevated symptoms of ADHD in Ontario, Canada. Parents completed a discrete-choice experiment (DCE) composed of 30 choice tasks used to gauge PT format preference. Results showed that 58.7% of parents preferred individual PT; these parents were most interested in interventions that would make them feel more informed about their child’s problems and in understanding—as opposed to solving—their child’s problems. A minority of parents (19.4 %) preferred group PT; these parents were most interested in active, skill-building services that would help them solve their child’s problems. About one-fifth of parents (21.9 %) preferred the Minimal Information alternative (i.e. receiving neither individual or group PT); these parents reported the highest levels of depression and the most severe mental health problems in their child. Results highlight the importance of considering parent preferences for format, and suggest that alternative formats to standard PT should be considered for multiply stressed families. PMID:25700219

  15. Cultural differences in complex addition: efficient Chinese versus adaptive Belgians and Canadians.

    PubMed

    Imbo, Ineke; LeFevre, Jo-Anne

    2009-11-01

    In the present study, the authors tested the effects of working-memory load on math problem solving in 3 different cultures: Flemish-speaking Belgians, English-speaking Canadians, and Chinese-speaking Chinese currently living in Canada. Participants solved complex addition problems (e.g., 58 + 76) in no-load and working-memory load conditions, in which either the central executive or the phonological loop was loaded. The authors used the choice/no-choice method to obtain unbiased measures of strategy selection and strategy efficiency. The Chinese participants were faster than the Belgians, who were faster and more accurate than the Canadians. The Chinese also required fewer working-memory resources than did the Belgians and Canadians. However, the Chinese chose less adaptively from the available strategies than did the Belgians and Canadians. These cultural differences in math problem solving are likely the result of different instructional approaches during elementary school (practice and training in Asian countries vs. exploration and flexibility in non-Asian countries), differences in the number language, and informal cultural norms and standards. The relevance of being adaptive is discussed as well as the implications of the results in regards to the strategy choice and discovery simulation model of strategy selection (J. Shrager & R. S. Siegler, 1998).

  16. Modeling Mode Choice Behavior Incorporating Household and Individual Sociodemographics and Travel Attributes Based on Rough Sets Theory

    PubMed Central

    Chen, Xuewu; Wei, Ming; Wu, Jingxian; Hou, Xianyao

    2014-01-01

    Most traditional mode choice models are based on the principle of random utility maximization derived from econometric theory. Alternatively, mode choice modeling can be regarded as a pattern recognition problem reflected from the explanatory variables of determining the choices between alternatives. The paper applies the knowledge discovery technique of rough sets theory to model travel mode choices incorporating household and individual sociodemographics and travel information, and to identify the significance of each attribute. The study uses the detailed travel diary survey data of Changxing county which contains information on both household and individual travel behaviors for model estimation and evaluation. The knowledge is presented in the form of easily understood IF-THEN statements or rules which reveal how each attribute influences mode choice behavior. These rules are then used to predict travel mode choices from information held about previously unseen individuals and the classification performance is assessed. The rough sets model shows high robustness and good predictive ability. The most significant condition attributes identified to determine travel mode choices are gender, distance, household annual income, and occupation. Comparative evaluation with the MNL model also proves that the rough sets model gives superior prediction accuracy and coverage on travel mode choice modeling. PMID:25431585

  17. The impact of approximations and arbitrary choices on geophysical images

    NASA Astrophysics Data System (ADS)

    Valentine, Andrew P.; Trampert, Jeannot

    2016-01-01

    Whenever a geophysical image is to be constructed, a variety of choices must be made. Some, such as those governing data selection and processing, or model parametrization, are somewhat arbitrary: there may be little reason to prefer one choice over another. Others, such as defining the theoretical framework within which the data are to be explained, may be more straightforward: typically, an `exact' theory exists, but various approximations may need to be adopted in order to make the imaging problem computationally tractable. Differences between any two images of the same system can be explained in terms of differences between these choices. Understanding the impact of each particular decision is essential if images are to be interpreted properly-but little progress has been made towards a quantitative treatment of this effect. In this paper, we consider a general linearized inverse problem, applicable to a wide range of imaging situations. We write down an expression for the difference between two images produced using similar inversion strategies, but where different choices have been made. This provides a framework within which inversion algorithms may be analysed, and allows us to consider how image effects may arise. In this paper, we take a general view, and do not specialize our discussion to any specific imaging problem or setup (beyond the restrictions implied by the use of linearized inversion techniques). In particular, we look at the concept of `hybrid inversion', in which highly accurate synthetic data (typically the result of an expensive numerical simulation) is combined with an inverse operator constructed based on theoretical approximations. It is generally supposed that this offers the benefits of using the more complete theory, without the full computational costs. We argue that the inverse operator is as important as the forward calculation in determining the accuracy of results. We illustrate this using a simple example, based on imaging the density structure of a vibrating string.

  18. Energy Choices for Consumers

    ERIC Educational Resources Information Center

    Nolan, William T.

    1977-01-01

    Sample problems concerning energy consumption and conservation with air conditioners, electric ranges, refrigerators and televisions are provided. The energy efficiency ratio (EER) is also discussed. (CP)

  19. Nicotine intake and problem solving strategies are modified during a cognitively demanding water maze task in rats.

    PubMed

    Nesil, Tanseli; Kanit, Lutfiye; Pogun, Sakire

    2015-11-01

    Nicotine is the major addictive component in tobacco, and despite well-established adverse health effects of tobacco addiction, some smokers have difficulty quitting. The acute cognitive enhancement and/or the amelioration of the cognitive disruption during withdrawal that some smokers experience after smoking are among important factors that hinder quit attempts. The animal model presented in the current study is comparable to the human smoking condition although nicotine intake routes are different. Rats were exposed to a free choice of oral nicotine starting at adolescence, and given a water maze (WM) task as adults. This design allowed us to see if rats alter their nicotine intake during the WM task and if nicotine preference and intake modify abilities and strategies rats use for problem solving. Male and female rats were exposed to a free choice of oral nicotine/water for 24weeks, starting at five weeks of age. After this period, they were selected based on their nicotine intake and, together with control animals that received only water, were subjected to a place-learning task in the WM. Free-choice nicotine exposure continued during WM testing. Following acquisition, the probe trial presented the rats with a choice between using two different strategies for problem solving. Nicotine supported acquisition and rats increased their nicotine intake during WM testing; this effect was more pronounced in male rats with minimum nicotine preference and intake. Furthermore, nicotine modified the "female type" strategy in solving the place-learning task and nicotine treated female rats, unlike control females, behaved like males. The increase in nicotine intake during mental engagement, and the sexually dimorphic effect of nicotine on problem solving strategies that we have observed in rats, may suggest that implementing sex-specific smoking cessation approaches, especially under stressful and cognitively demanding conditions, may be useful in helping smokers quit. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Open problem-based instruction impacts understanding of physiological concepts differently in undergraduate students

    PubMed Central

    Franklin, Brandon M.; Xiang, Lin; Collett, Jason A.; Rhoads, Megan K.

    2015-01-01

    Student populations are diverse such that different types of learners struggle with traditional didactic instruction. Problem-based learning has existed for several decades, but there is still controversy regarding the optimal mode of instruction to ensure success at all levels of students' past achievement. The present study addressed this problem by dividing students into the following three instructional groups for an upper-level course in animal physiology: traditional lecture-style instruction (LI), guided problem-based instruction (GPBI), and open problem-based instruction (OPBI). Student performance was measured by three summative assessments consisting of 50% multiple-choice questions and 50% short-answer questions as well as a final overall course assessment. The present study also examined how students of different academic achievement histories performed under each instructional method. When student achievement levels were not considered, the effects of instructional methods on student outcomes were modest; OPBI students performed moderately better on short-answer exam questions than both LI and GPBI groups. High-achieving students showed no difference in performance for any of the instructional methods on any metric examined. In students with low-achieving academic histories, OPBI students largely outperformed LI students on all metrics (short-answer exam: P < 0.05, d = 1.865; multiple-choice question exam: P < 0.05, d = 1.166; and final score: P < 0.05, d = 1.265). They also outperformed GPBI students on short-answer exam questions (P < 0.05, d = 1.109) but not multiple-choice exam questions (P = 0.071, d = 0.716) or final course outcome (P = 0.328, d = 0.513). These findings strongly suggest that typically low-achieving students perform at a higher level under OPBI as long as the proper support systems (formative assessment and scaffolding) are provided to encourage student success. PMID:26628656

  1. Work Status Choice and the Distribution of Family Earnings.

    DTIC Science & Technology

    1984-11-01

    were in the market. Since wages for secondary earners are observable only for market participants, censoring corrections will have to be made to...obtain the true correlation of earners’ earnings. The problem of censoring corrections has been extensively studied in the female labor supply...earners are defined to be male members other than the HH. The censoring framework is fairly similar to the occupation-choice model discussed earlier

  2. Solving Geometric Problems by Using Algebraic Representation for Junior High School Level 3 in Van Hiele at Geometric Thinking Level

    ERIC Educational Resources Information Center

    Suwito, Abi; Yuwono, Ipung; Parta, I. Nengah; Irawati, Santi; Oktavianingtyas, Ervin

    2016-01-01

    This study aims to determine the ability of algebra students who have 3 levels van Hiele levels. Follow its framework Dindyal framework (2007). Students are required to do 10 algebra shaped multiple choice, then students work 15 about the geometry of the van Hiele level in the form of multiple choice questions. The question has been tested levels…

  3. Diet-induced impulsivity: Effects of a high-fat and a high-sugar diet on impulsive choice in rats

    PubMed Central

    Pirkle, Jesseca R. A.; Kirkpatrick, Kimberly

    2017-01-01

    Impulsive choice is a common charactertistic among individuals with gambling problems, obesity, and substance abuse issues. Impulsive choice has been classified as a trans-disease process, and understanding the etiology of trait impulsivity could help to understand how diseases and disorders related to impulsive choice are manifested. The Western diet is a possible catalyst of impulsive choice as individuals who are obese and who eat diets high in fat and sugar are typically more impulsive. However, such correlational evidence is unable to discern the direction and causal nature of the relationship. The present study sought to determine how diet may directly contribute to impulsive choice. After 8 weeks of dietary exposure (high-fat, high-sugar, chow), the rats were tested on an impulsive choice task, which presented choices between a smaller-sooner reward (SS) and a larger-later reward (LL). Then, the rats were transferred to a chow diet and retested on the impulsive choice task. The high-sugar and high-fat groups made significantly more impulsive choices than the chow group. Both groups became more self-controlled when they were off the diet, but there were some residual effects of the diet on choice behavior. These results suggest that diet, specifically one high in processed fat or sugar, induces impulsive choice. This diet-induced impulsivity could be a precursor to other disorders that are characterized by impulsivity, such as diet-induced obesity, and could offer potential understanding of the trans-disease nature of impulsive choice. PMID:28662133

  4. Diet-induced impulsivity: Effects of a high-fat and a high-sugar diet on impulsive choice in rats.

    PubMed

    Steele, Catherine C; Pirkle, Jesseca R A; Kirkpatrick, Kimberly

    2017-01-01

    Impulsive choice is a common charactertistic among individuals with gambling problems, obesity, and substance abuse issues. Impulsive choice has been classified as a trans-disease process, and understanding the etiology of trait impulsivity could help to understand how diseases and disorders related to impulsive choice are manifested. The Western diet is a possible catalyst of impulsive choice as individuals who are obese and who eat diets high in fat and sugar are typically more impulsive. However, such correlational evidence is unable to discern the direction and causal nature of the relationship. The present study sought to determine how diet may directly contribute to impulsive choice. After 8 weeks of dietary exposure (high-fat, high-sugar, chow), the rats were tested on an impulsive choice task, which presented choices between a smaller-sooner reward (SS) and a larger-later reward (LL). Then, the rats were transferred to a chow diet and retested on the impulsive choice task. The high-sugar and high-fat groups made significantly more impulsive choices than the chow group. Both groups became more self-controlled when they were off the diet, but there were some residual effects of the diet on choice behavior. These results suggest that diet, specifically one high in processed fat or sugar, induces impulsive choice. This diet-induced impulsivity could be a precursor to other disorders that are characterized by impulsivity, such as diet-induced obesity, and could offer potential understanding of the trans-disease nature of impulsive choice.

  5. Efficient computation of optimal actions.

    PubMed

    Todorov, Emanuel

    2009-07-14

    Optimal choice of actions is a fundamental problem relevant to fields as diverse as neuroscience, psychology, economics, computer science, and control engineering. Despite this broad relevance the abstract setting is similar: we have an agent choosing actions over time, an uncertain dynamical system whose state is affected by those actions, and a performance criterion that the agent seeks to optimize. Solving problems of this kind remains hard, in part, because of overly generic formulations. Here, we propose a more structured formulation that greatly simplifies the construction of optimal control laws in both discrete and continuous domains. An exhaustive search over actions is avoided and the problem becomes linear. This yields algorithms that outperform Dynamic Programming and Reinforcement Learning, and thereby solve traditional problems more efficiently. Our framework also enables computations that were not possible before: composing optimal control laws by mixing primitives, applying deterministic methods to stochastic systems, quantifying the benefits of error tolerance, and inferring goals from behavioral data via convex optimization. Development of a general class of easily solvable problems tends to accelerate progress--as linear systems theory has done, for example. Our framework may have similar impact in fields where optimal choice of actions is relevant.

  6. Hypothetical contractarianism and the disclosure requirement problem in informed consent.

    PubMed

    Cust, Kenneth F T

    1991-01-01

    Two of the more deeply problematic issues surrounding the doctrine of informed consent are providing a justification for the practice of informed consent and providing an account of the nature and amount of information that must be disclosed in order for informed consent to take place. This paper is concerned with the latter problem, the problem of disclosure requirements, but it deals with this problem in a novel way; it approaches the problem by asking what fully informed and fully rational agents would agree to under certain hypothetical conditions. In general terms I juxtapose the hypothetical contractarianism found in Rawls' A Theory of Justice with that found in Gauthier's Morals By Agreement and ask what their respective hypothetical contractors would agree to with respect to choosing a particular standard of disclosure to govern the practice of informed consent. In more specific terms a contrast is made between what a Rawlsian agent behind a veil of ignorance would choose as compared to what, in Gauthier's terms, an ideal actor making an Archimedean choice would choose. The idea of an Archimedean point, and the subsequent choice made from that point, although technically identified by Rawls, originated with Archimedes of Syracuse.

  7. Issues or Identity? Cognitive Foundations of Voter Choice.

    PubMed

    Jenke, Libby; Huettel, Scott A

    2016-11-01

    Voter choice is one of the most important problems in political science. The most common models assume that voting is a rational choice based on policy positions (e.g., key issues) and nonpolicy information (e.g., social identity, personality). Though such models explain macroscopic features of elections, they also reveal important anomalies that have been resistant to explanation. We argue for a new approach that builds upon recent research in cognitive science and neuroscience; specifically, we contend that policy positions and social identities do not combine in merely an additive manner, but compete to determine voter preferences. This model not only explains several key anomalies in voter choice, but also suggests new directions for research in both political science and cognitive science. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Simplest chronoscope. III. Further comparisons between reaction times obtained by meterstick versus machine.

    PubMed

    Montare, Alberto

    2013-06-01

    The three classical Donders' reaction time (RT) tasks (simple, choice, and discriminative RTs) were employed to compare reaction time scores from college students obtained by use of Montare's simplest chronoscope (meterstick) methodology to scores obtained by use of a digital-readout multi-choice reaction timer (machine). Five hypotheses were tested. Simple RT, choice RT, and discriminative RT were faster when obtained by meterstick than by machine. The meterstick method showed higher reliability than the machine method and was less variable. The meterstick method of the simplest chronoscope may help to alleviate the longstanding problems of low reliability and high variability of reaction time performances; while at the same time producing faster performance on Donders' simple, choice and discriminative RT tasks than the machine method.

  9. Using Reflection with Peers to Help Students Learn Effective Problem Solving Strategies

    NASA Astrophysics Data System (ADS)

    Mason, Andrew; Singh, Chandralekha

    2010-10-01

    We describe a study in which introductory physics students engage in reflection with peers about problem solving. The recitations for an introductory physics course with 200 students were broken into the "Peer Reflection" (PR) group and the traditional group. Each week in recitation, students in the PR group reflected in small teams on selected problems from the homework. The graduate and undergraduate teaching assistants (TAs) in the PR group recitations provided guidance and coaching to help students learn effective problem solving heuristics. In the recitations for the traditional group, students had the opportunity to ask the graduate TA questions about the homework before they took a weekly quiz. On the final exam with only multiple-choice questions, the PR group drew diagrams on more problems than the traditional group, even when there was no external reward for doing so. Since there was no partial credit for drawing the diagrams on the scratch books, students did not draw diagrams simply to get credit for the effort shown and must value the use of diagrams for solving problems if they drew them. We also find that, regardless of whether the students belonged to the traditional or PR groups, those who drew more diagrams for the multiple-choice questions outperformed those who did not draw them.

  10. Inter-Industry Wage Differentials and the Gender Wage Gap: An Identification Problem.

    ERIC Educational Resources Information Center

    Horrace, William C.; Oaxaca, Ronald L.

    2001-01-01

    States that a method for estimating gender wage gaps by industry yields estimates that vary according to arbitrary choice of omitted reference groups. Suggests alternative methods not susceptible to this problem that can be applied to other contexts, such as racial, union/nonunion, and immigrant/native wage differences. (SK)

  11. Cyberbullying from the Perspective of Choice Theory

    ERIC Educational Resources Information Center

    Tanrikulu, Taskin

    2014-01-01

    This study aims to propose a theoretical explanation for the cyberbullying problem, which is the use of cyber communication tools to endanger other people. In recent years, the cyberbullying problem, which is widespread especially among the young, has been the subject of scientific studies. These studies have mostly focused on the issues of causes…

  12. Mobile Devices at School: Possibilities, Problems, and Tough Choices

    ERIC Educational Resources Information Center

    Adams, Dennis; Angeles, Rebecca

    2008-01-01

    This article takes a "point/counterpoint" approach to considering the educational use of mobile devices. It views the possibilities and problems surrounding the use of small laptops, cellphones, iPhones, etc. Although clear answers to questions regarding the classroom use of digital devices are hard to come by, the authors believe that educators…

  13. The (Even) Bolder Model: The Clinical Psychologist as Metaphysician-Scientist-Practitioner.

    ERIC Educational Resources Information Center

    O'Donohue, William

    1989-01-01

    Examines the roles of metaphysics in science and psychotherapy. Examines the views of Karl Popper and Imre Lakatos. Concludes that psychotherapy involves metaphysics in the following ways: (1) problem choice; (2) research and therapy design; (3) observation statements; (4) resolving the Duhemian problem; and (5) including anomalous results in…

  14. Document image improvement for OCR as a classification problem

    NASA Astrophysics Data System (ADS)

    Summers, Kristen M.

    2003-01-01

    In support of the goal of automatically selecting methods of enhancing an image to improve the accuracy of OCR on that image, we consider the problem of determining whether to apply each of a set of methods as a supervised classification problem for machine learning. We characterize each image according to a combination of two sets of measures: a set that are intended to reflect the degree of particular types of noise present in documents in a single font of Roman or similar script and a more general set based on connected component statistics. We consider several potential methods of image improvement, each of which constitutes its own 2-class classification problem, according to whether transforming the image with this method improves the accuracy of OCR. In our experiments, the results varied for the different image transformation methods, but the system made the correct choice in 77% of the cases in which the decision affected the OCR score (in the range [0,1]) by at least .01, and it made the correct choice 64% of the time overall.

  15. Choosing among possible persons: The ethics of prenatal selection in the postgenomic age.

    PubMed

    Mauron, Alex

    2015-01-01

    The "spectre of eugenics" is often raised about various current reproductive practices that imply a form of choice between future possible persons. Some of these practices are linked to genetic technologies such as pre-implantation genetic diagnosis, others merely entail the choice of a procreator having specific traits, such as in artificial insemination with donor. The weight and limits of this reproof of eugenics are examined, with special attention to the conceptual problems resulting from confusing choices involving virtual persons with the selection of existing persons. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  16. Lifestyle choices and mental health: a longitudinal survey with German and Chinese students.

    PubMed

    Velten, Julia; Bieda, Angela; Scholten, Saskia; Wannemüller, André; Margraf, Jürgen

    2018-05-16

    A healthy lifestyle can be beneficial for one's mental health. Thus, identifying healthy lifestyle choices that promote psychological well-being and reduce mental problems is useful to prevent mental disorders. The aim of this longitudinal study was to evaluate the predictive values of a broad range of lifestyle choices for positive mental health (PMH) and mental health problems (MHP) in German and Chinese students. Data were assessed at baseline and at 1-year follow-up. Samples included 2991 German (M age  = 21.69, SD = 4.07) and 12,405 Chinese (M age  = 20.59, SD = 1.58) university students. Lifestyle choices were body mass index, frequency of physical and mental activities, frequency of alcohol consumption, smoking, vegetarian diet, and social rhythm irregularity. PMH and MHP were measured with the Positive Mental Health Scale and a 21-item version of the Depression Anxiety and Stress Scale. The predictive values of lifestyle choices for PMH and MHP at baseline and follow-up were assessed with single-group and multi-group path analyses. Better mental health (higher PMH and fewer MHP) at baseline was predicted by a lower body mass index, a higher frequency of physical and mental activities, non-smoking, a non-vegetarian diet, and a more regular social rhythm. When controlling for baseline mental health, age, and gender, physical activity was a positive predictor of PMH, smoking was a positive predictor of MHP, and a more irregular social rhythm was a positive predictor of PMH and a negative predictor of MHP at follow-up. The good fit of a multi-group model indicated that most lifestyle choices predict mental health comparably across samples. Some country-specific effects emerged: frequency of alcohol consumption, for example, predicted better mental health in German and poorer mental health in Chinese students. Our findings underline the importance of healthy lifestyle choices for improved psychological well-being and fewer mental health difficulties. Effects of lifestyle on mental health are comparable in German and Chinese students. Some healthy lifestyle choices (i.e., more frequent physical activity, non-smoking, regular social rhythm) are related to improvements in mental health over a 1-year period.

  17. Determinants of choice, and vulnerability and recovery in addiction.

    PubMed

    Lamb, R J; Maguire, David R; Ginsburg, Brett C; Pinkston, Jonathan W; France, Charles P

    2016-06-01

    Addiction may be viewed as choice governed by competing contingencies. One factor impacting choice, particularly as it relates to addiction, is sensitivity to delayed rewards. Discounting of delayed rewards influences addiction vulnerability because of competition between relatively immediate gains of drug use, e.g. intoxication, versus relatively remote gains of abstinence, e.g. family stability. Factors modifying delay sensitivity can be modeled in the laboratory. For instance, increased delay sensitivity can be similarly observed in adolescent humans and non-human animals. Similarly, genetic factors influence delay sensitivity in humans and animals. Recovery from addiction may also be viewed as choice behavior. Thus, reinforcing alternative behavior facilitates recovery because reinforcing alternative behavior decreases the frequency of using drugs. How reinforcing alternative behavior influences recovery can also be modeled in the laboratory. For instance, relapse risk decreases as abstinence duration increases, and this decreasing risk can be modeled in animals using choice procedures. In summary, addiction in many respects can be conceptualized as a problem of choice. Animal models of choice disorders stand to increase our understanding of the core processes that establish and maintain addiction and serve as a proving ground for development of novel treatments. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Determinants of choice, and vulnerability and recovery in addiction

    PubMed Central

    Lamb, R.J.; Maguire, David R.; Ginsburg, Brett C.; Pinkston, Jonathan W.; France, Charles P.

    2016-01-01

    Addiction may be viewed as choice governed by competing contingencies. One factor impacting choice, particularly as it relates to addiction, is sensitivity to delayed rewards. Discounting of delayed rewards influences addiction vulnerability because of competition between relatively immediate gains of drug use, e.g. intoxication, versus relatively remote gains of abstinence, e.g. family stability. Factors modifying delay sensitivity can be modeled in the laboratory. For instance, increased delay sensitivity can be similarly observed in adolescent humans and non-human animals. Similarly, genetic factors influence delay sensitivity in humans and animals. Recovery from addiction may also be viewed as choice behavior. Thus, reinforcing alternative behavior facilitates recovery because reinforcing alternative behavior decreases the frequency of using drugs. How reinforcing alternative behavior influences recovery can also be modeled in the laboratory. For instance, relapse risk decreases as abstinence duration increases, and this decreasing risk can be modeled in animals using choice procedures. In summary, addiction in many respects can be conceptualized as a problem of choice. Animal models of choice disorders stand to increase our understanding of the core processes that establish and maintain addiction and serve as a proving ground for development of novel treatments. PMID:27083500

  19. Strategic and non-strategic problem gamblers differ on decision-making under risk and ambiguity.

    PubMed

    Lorains, Felicity K; Dowling, Nicki A; Enticott, Peter G; Bradshaw, John L; Trueblood, Jennifer S; Stout, Julie C

    2014-07-01

    To analyse problem gamblers' decision-making under conditions of risk and ambiguity, investigate underlying psychological factors associated with their choice behaviour and examine whether decision-making differed in strategic (e.g., sports betting) and non-strategic (e.g., electronic gaming machine) problem gamblers. Cross-sectional study. Out-patient treatment centres and university testing facilities in Victoria, Australia. Thirty-nine problem gamblers and 41 age, gender and estimated IQ-matched controls. Decision-making tasks included the Iowa Gambling Task (IGT) and a loss aversion task. The Prospect Valence Learning (PVL) model was used to provide an explanation of cognitive, motivational and response style factors involved in IGT performance. Overall, problem gamblers performed more poorly than controls on both the IGT (P = 0.04) and the loss aversion task (P = 0.01), and their IGT decisions were associated with heightened attention to gains (P = 0.003) and less consistency (P = 0.002). Strategic problem gamblers did not differ from matched controls on either decision-making task, but non-strategic problem gamblers performed worse on both the IGT (P = 0.006) and the loss aversion task (P = 0.02). Furthermore, we found differences in the PVL model parameters underlying strategic and non-strategic problem gamblers' choices on the IGT. Problem gamblers demonstrated poor decision-making under conditions of risk and ambiguity. Strategic (e.g. sports betting, poker) and non-strategic (e.g. electronic gaming machines) problem gamblers differed in decision-making and the underlying psychological processes associated with their decisions. © 2014 Society for the Study of Addiction.

  20. Investigating Proenvironmental Behavior: The Case of Commuting Mode Choice

    NASA Astrophysics Data System (ADS)

    Trinh, Tu Anh; Phuong Linh Le, Thi

    2018-04-01

    The central aim of this article is to investigate mode choice behavior among commuters in Ho Chi Minh City using disaggregate mode choice model and norm activation theory. A better understanding of commuters’ choice of transport mode provide an opportunity to obtain valuable information on their travel behaviors which help to build a basic for proffering solutions stimulating commuters to switch to public transport, which in turn contribute to deal with traffic problems and environmental issues. Binary logistic regression was employed under disaggregate choice method. Key findings indicated that Demographic factors including Age (-0.308), Married (-9.089), Weather (-8.272); Trip factors including Travel cost (0.437), Travel distance (0.252), and Norm activation theory (Awareness of consequences: AC2 (-1.699), AC4 (2.951), AC6 (-3.523), AC7 (-2.092), AC9 (-3.045), AC11 (+ 2.939), and Personal norms: PN2 (-2.695)) had strong impact on the commuters’ mode choice. Although motorcycle was the major transport mode among commuters, they presented their willingness to switch to bus transport if it had less negative impacts on the environment and their daily living environment.

  1. [A multi-measure analysis of the similarity, attraction, and compromise effects in multi-attribute decision making].

    PubMed

    Tsuzuki, Takashi; Matsui, Hiroshi; Kikuchi, Manabu

    2012-12-01

    In multi-attribute decision making, the similarity, attraction, and compromise effects warrant specific investigation as they cause violations of principles in rational choice. In order to investigate these three effects simultaneously, we assigned 145 undergraduates to three context effect conditions. We requested them to solve the same 20 hypothetical purchase problems, each of which had three alternatives described along two attributes. We measured their choices, confidence ratings, and response times. We found that manipulating the third alternative had significant context effects for choice proportions and confidence ratings in all three conditions. Furthermore, the attraction effect was the most prominent with regard to choice proportions. In the compromise effect condition, although the choice proportion of the third alternative was high, the confidence rating was low and the response time was long. These results indicate that the relationship between choice proportions and confidence ratings requires further theoretical investigation. They also suggest that a combination of experimental and modeling studies is imperative to reveal the mechanisms underlying the context effects in multi-attribute, multi-alternative decision making.

  2. Simultaneous and semi-alternating projection algorithms for solving split equality problems.

    PubMed

    Dong, Qiao-Li; Jiang, Dan

    2018-01-01

    In this article, we first introduce two simultaneous projection algorithms for solving the split equality problem by using a new choice of the stepsize, and then propose two semi-alternating projection algorithms. The weak convergence of the proposed algorithms is analyzed under standard conditions. As applications, we extend the results to solve the split feasibility problem. Finally, a numerical example is presented to illustrate the efficiency and advantage of the proposed algorithms.

  3. Les Representations Graphiques Dans La Resolution De Problemes: Une Experience D'Entrainement D'Etudiants Dans Un Club Mathematique (Graphic Representations in Problem Solving: A Training Program for Students in a Mathematical Club).

    ERIC Educational Resources Information Center

    Callejo, Maria Luz

    1994-01-01

    Reports, in French, an investigation on the use of graphic representations in problem-solving tasks of the type in Spanish Mathematical Olympiads. Analysis showed that the choice and interpretation of the first graphic representation played a decisive role in the discovery of the solution. (34 references) (Author/MKR)

  4. How to choose a calving law

    NASA Astrophysics Data System (ADS)

    O'Leary, M.

    2014-12-01

    Any model of an ocean-terminating ice mass requires a frontal boundary condition, often referred to as a "calving law". The choice of this boundary condition can have complex and poorly-understood effects on the behaviour of the system. Despite this, calving laws are often chosen based on numerical convenience or fashions in the literature. This can often lead to predictions which have "hidden dependencies" on the particular choice of calving law. As an attempt to alleviate this problem, I will show results from a wide variety of calving laws, applied to tidewater glacier scenarios. I will demonstrate how the decadal-scale stability of a tidewater system can put constraints on possible calving laws, and how certain observational phenomena, such as the presence of "pinning points" are largely independent of the choice of calving law. These results can be used by practitioners to decide on appropriate calving laws for the specific problems at hand. They should also be useful to help direct research into new calving laws, and to guide our conception of what an ideal calving law should look like.

  5. Design-Filter Selection for H2 Control of Microgravity Isolation Systems: A Single-Degree-of-Freedom Case Study

    NASA Technical Reports Server (NTRS)

    Hampton, R. David; Whorton, Mark S.

    2000-01-01

    Many microgravity space-science experiments require active vibration isolation, to attain suitably low levels of background acceleration for useful experimental results. The design of state-space controllers by optimal control methods requires judicious choices of frequency-weighting design filters. Kinematic coupling among states greatly clouds designer intuition in the choices of these filters, and the masking effects of the state observations cloud the process further. Recent research into the practical application of H2 synthesis methods to such problems, indicates that certain steps can lead to state frequency-weighting design-filter choices with substantially improved promise of usefulness, even in the face of these difficulties. In choosing these filters on the states, one considers their relationships to corresponding design filters on appropriate pseudo-sensitivity- and pseudo-complementary-sensitivity functions. This paper investigates the application of these considerations to a single-degree-of-freedom microgravity vibration-isolation test case. Significant observations that were noted during the design process are presented. along with explanations based on the existent theory for such problems.

  6. Interacting holographic dark energy models: a general approach

    NASA Astrophysics Data System (ADS)

    Som, S.; Sil, A.

    2014-08-01

    Dark energy models inspired by the cosmological holographic principle are studied in homogeneous isotropic spacetime with a general choice for the dark energy density . Special choices of the parameters enable us to obtain three different holographic models, including the holographic Ricci dark energy (RDE) model. Effect of interaction between dark matter and dark energy on the dynamics of those models are investigated for different popular forms of interaction. It is found that crossing of phantom divide can be avoided in RDE models for β>0.5 irrespective of the presence of interaction. A choice of α=1 and β=2/3 leads to a varying Λ-like model introducing an IR cutoff length Λ -1/2. It is concluded that among the popular choices an interaction of the form Q∝ Hρ m suits the best in avoiding the coincidence problem in this model.

  7. Conceptualising a child-centric paradigm : do we have freedom of choice in donor conception reproduction?

    PubMed

    Adams, Damian H

    2013-10-01

    Since its inception, donor conception practices have been a reproductive choice for the infertile. Past and current practices have the potential to cause significant and lifelong harm to the offspring through loss of kinship, heritage, identity, and family health history, and possibly through introducing physical problems. Legislation and regulation in Australia that specifies that the welfare of the child born as a consequence of donor conception is paramount may therefore be in conflict with the outcomes. Altering the paradigm to a child-centric model, however, impinges on reproductive choice and rights of adults involved in the process. With some lobby groups pushing for increased reproductive choice while others emphasise offspring rights there is a dichotomy of interests that society and legislators need to address. Concepts pertaining to a shift toward a child-centric paradigm are discussed.

  8. The selection criteria elements of X-ray optics system

    NASA Astrophysics Data System (ADS)

    Plotnikova, I. V.; Chicherina, N. V.; Bays, S. S.; Bildanov, R. G.; Stary, O.

    2018-01-01

    At the design of new modifications of x-ray tomography there are difficulties in the right choice of elements of X-ray optical system. Now this problem is solved by practical consideration, selection of values of the corresponding parameters - tension on an x-ray tube taking into account the thickness and type of the studied material. For reduction of time and labor input of design it is necessary to create the criteria of the choice, to determine key parameters and characteristics of elements. In the article two main elements of X-ray optical system - an x-ray tube and the detector of x-ray radiation - are considered. Criteria of the choice of elements, their key characteristics, the main dependences of parameters, quality indicators and also recommendations according to the choice of elements of x-ray systems are received.

  9. Drunk decisions: Alcohol shifts choice from habitual towards goal-directed control in adolescent intermediate-risk drinkers.

    PubMed

    Obst, Elisabeth; Schad, Daniel J; Huys, Quentin Jm; Sebold, Miriam; Nebe, Stephan; Sommer, Christian; Smolka, Michael N; Zimmermann, Ulrich S

    2018-05-01

    Studies in humans and animals suggest a shift from goal-directed to habitual decision-making in addiction. We therefore tested whether acute alcohol administration reduces goal-directed and promotes habitual decision-making, and whether these effects are moderated by self-reported drinking problems. Fifty-three socially drinking males completed the two-step task in a randomised crossover design while receiving an intravenous infusion of ethanol (blood alcohol level=80 mg%), or placebo. To minimise potential bias by long-standing heavy drinking and subsequent neuropsychological impairment, we tested 18- to 19-year-old adolescents. Alcohol administration consistently reduced habitual, model-free decisions, while its effects on goal-directed, model-based behaviour varied as a function of drinking problems measured with the Alcohol Use Disorders Identification Test. While adolescents with low risk for drinking problems (scoring <8) exhibited an alcohol-induced numerical reduction in goal-directed choices, intermediate-risk drinkers showed a shift away from habitual towards goal-directed decision-making, such that alcohol possibly even improved their performance. We assume that alcohol disrupted basic cognitive functions underlying habitual and goal-directed decisions in low-risk drinkers, thereby enhancing hasty choices. Further, we speculate that intermediate-risk drinkers benefited from alcohol as a negative reinforcer that reduced unpleasant emotional states, possibly displaying a novel risk factor for drinking in adolescence.

  10. Theory of protective empowering for balancing patient safety and choices.

    PubMed

    Chiovitti, Rosalina F

    2011-01-01

    Registered nurses in psychiatric-mental health nursing continuously balance the ethical principles of duty to do good (beneficence) and no harm (non-maleficence) with the duty to respect patient choices (autonomy). However, the problem of nurses' level of control versus patients' choices remains a challenge. The aim of this article is to discuss how nurses accomplish their simultaneous responsibility for balancing patient safety (beneficence and non-maleficence) with patient choices (autonomy) through the theory of protective empowering. This is done by reflecting on interview excerpts about caring from 17 registered nurses taking part in a grounded theory study conducted in three acute urban psychiatric hospital settings in Canada. The interplay between the protective and empowering dimensions of the theory of protective empowering was found to correspond with international, national, and local nursing codes of ethics and standards. The overall core process of protective empowering, and its associated reflective questions, is offered as a new lens for balancing patient safety with choices.

  11. How to make moral choices.

    PubMed

    Chambers, David W

    2011-01-01

    Moral choice is committing to act for what one believes is right and good. It is less about what we know than about defining who we are. Three cases typical of those used in the principles or dilemmas approach to teaching ethics are presented. But they are analyzed using an alternative approach based on seven moral choice heuristics--approaches proven to increase the likelihood of locating the best course of action. The approaches suggested for analyzing moral choice situations include: (a) identify the outcomes of available alternative courses of action; (b) rule out strategies that involve deception, coercion, reneging on promises, collusion, and contempt for others; (c) be authentic (do not deceive yourself); (d) relate to others on a human basis; (e) downplay rational justifications; (f) match the solution to the problem, not the other way around; (g) execute on the best solution, do not hold out for the perfect one; and (h) take action to improve the choice after it has been made.

  12. "Righting" the Writing Problem.

    ERIC Educational Resources Information Center

    Shaughnessy, Michael F.; Eastham, Nicholas

    The problem of college students' writing skills or lack thereof is generally agreed upon in academia. One cause is the inordinate amount of multiple choice/true false/fill in the blank type of tests that students take in high school and college. Not only is there is a dearth of actual classes in writing available, few students recognize the need…

  13. Facts about Texas Children. Excerpted from Children, Choice, and Change.

    ERIC Educational Resources Information Center

    Harris, Lorwen Connie

    The environment in which Texas children grow up is crucial to their future and to the future of the state. Almost 500,000 Texas families were poor in 1985. Poverty sets the stage for numerous childhood maladies: infant mortality, health problems, child abuse, learning disabilities, malnutrition, and mental health problems. As poor children grow up…

  14. Cost Containment: An Economist's View

    PubMed Central

    Neuhauser, Duncan

    1980-01-01

    Rising medical care costs are not the problem they seem to be, in part because quality of care is not considered. The problem may be more the absence of choice of alternative health benefit packages with price differences. The future of health services in the United States will have more competing alternatives requiring physicians to be more cost conscious. PMID:6992461

  15. Psychological Help-Seeking Intention among College Students across Three Problem Areas

    ERIC Educational Resources Information Center

    Hess, Timothy R.; Tracey, Terence J. G.

    2013-01-01

    The theory of planned behavior (TPB) was used to understand psychological help-seeking intention for 3 common concerns: anxiety or depression, career choice concerns, and alcohol or drug use. Eight hundred eighty-nine university students completed surveys for the TPB variables plus belief in personal efficacy and control to solve the problems.…

  16. Conduct Problems and Peer Rejection in Childhood: A Randomized Trial of the Making Choices and Strong Families Programs

    ERIC Educational Resources Information Center

    Fraser, Mark W.; Day, Steven H.; Galinsky, Maeda J.; Hodges, Vanessa G.; Smokowski, Paul R.

    2004-01-01

    This article discusses the effectiveness of a multicomponent intervention designed to disrupt developmental processes associated with conduct problems and peer rejection in childhood. Compared with 41 children randomized to a wait list control condition, 45 children in an intervention condition received a social skills training program. At the…

  17. Social and Economic Trends in Rural America. The White House Rural Development Background Paper.

    ERIC Educational Resources Information Center

    Deavers, Kenneth L.; Brown, David L.

    Emphasizing developmental problems caused by the rapid population and employment growth in rural America during the 1970's, this document describes social, economic, and governmental trends in rural America and suggests some federal policy choices that might be made in support of rural development. Problem areas and policy suggestions are…

  18. Recognizing Value of Educational Collaboration between High Schools and Universities Facilitated by Modern ICT

    ERIC Educational Resources Information Center

    Zielinski, K.; Czekierda, L.; Malawski, F.; Stras, R.; Zielinski, S.

    2017-01-01

    In this paper, we address the problem of an educational gap existing between high schools and universities: many students consider their choice of field of study as inappropriate, mostly due to insufficient information regarding the discipline and the university educational process. To solve this problem, we define an innovative, information and…

  19. Testing Boundary Conditions for the Conjunction Fallacy: Effects of Response Mode, Conceptual Focus, and Problem Type

    ERIC Educational Resources Information Center

    Wedell, Douglas H.; Moro, Rodrigo

    2008-01-01

    Two experiments used within-subject designs to examine how conjunction errors depend on the use of (1) choice versus estimation tasks, (2) probability versus frequency language, and (3) conjunctions of two likely events versus conjunctions of likely and unlikely events. All problems included a three-option format verified to minimize…

  20. An Examination of Preservice Teachers' Capacity to Create Mathematical Modeling Problems for Children

    ERIC Educational Resources Information Center

    Paolucci, Catherine; Wessels, Helena

    2017-01-01

    This study examined preservice teachers' (PSTs) capacity to create mathematical modeling problems (MMPs) for grades 1 to 3. PSTs created MMPs for their choice of grade level and aligned the mathematical content of their MMPs with the relevant mathematics curriculum. PSTs were given criteria adapted from Galbraith's MMP design principles to guide…

  1. Group Problem Solving as a Different Participatory Approach to Citizenship Education

    ERIC Educational Resources Information Center

    Guérin, Laurence

    2017-01-01

    Purpose: The main goal of this article is to learning define and justify group problem solving as an approach to citizenship education. It is demonstrated that the choice of theoretical framework of democracy has consequences for the chosen learning goals, educational approach and learning activities. The framework used here is an epistemic theory…

  2. School Racial Composition and Parental Choice: New Evidence on the Preferences of White Parents in the United States

    ERIC Educational Resources Information Center

    Billingham, Chase M.; Hunt, Matthew O.

    2016-01-01

    Racial segregation remains a persistent problem in U.S. schools. In this article, we examine how social psychological factors--in particular, individuals' perceptions of schools with varying demographic characteristics--may contribute to the ongoing structural problem of school segregation. We investigate the effects of school racial composition…

  3. Computational Fluency and Strategy Choice Predict Individual and Cross-National Differences in Complex Arithmetic

    ERIC Educational Resources Information Center

    Vasilyeva, Marina; Laski, Elida V.; Shen, Chen

    2015-01-01

    The present study tested the hypothesis that children's fluency with basic number facts and knowledge of computational strategies, derived from early arithmetic experience, predicts their performance on complex arithmetic problems. First-grade students from United States and Taiwan (N = 152, mean age: 7.3 years) were presented with problems that…

  4. Further Examination of Factors that Influence Preference for Positive versus Negative Reinforcement

    ERIC Educational Resources Information Center

    Kodak, Tiffany; Lerman, Dorothea C.; Volkert, Valerie M.; Trosclair, Nicole

    2007-01-01

    Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer…

  5. Improving the Mental Health, Healthy Lifestyle Choices, and Physical Health of Hispanic Adolescents: A Randomized Controlled Pilot Study

    ERIC Educational Resources Information Center

    Melnyk, Bernadette M.; Jacobson, Diana; Kelly, Stephanie; O'Haver, Judith; Small, Leigh; Mays, Mary Z.

    2009-01-01

    Background: Obesity and mental health disorders are 2 major public health problems in American adolescents, with prevalence even higher in Hispanic teens. Despite the rapidly increasing incidence and adverse health outcomes associated with overweight and mental health problems, very few intervention studies have been conducted with adolescents to…

  6. Who Is Listening? An Examination of Gender Effects and Employment Choice in Sustainability Education in an Undergraduate Business School

    ERIC Educational Resources Information Center

    Weaven, Scott; Griffin, Deborah; McPhail, Ruth; Smith, Calvin

    2013-01-01

    Whilst universities acknowledge the importance of sustainability education, numerous problems exist in relation to the nature, delivery and outcomes of sustainability instruction. Many of these problems arise due to a lack of understanding about students' perception towards, and knowledge about business sustainability. This article examines…

  7. Framing From Experience: Cognitive Processes and Predictions of Risky Choice.

    PubMed

    Gonzalez, Cleotilde; Mehlhorn, Katja

    2016-07-01

    A framing bias shows risk aversion in problems framed as "gains" and risk seeking in problems framed as "losses," even when these are objectively equivalent and probabilities and outcomes values are explicitly provided. We test this framing bias in situations where decision makers rely on their own experience, sampling the problem's options (safe and risky) and seeing the outcomes before making a choice. In Experiment 1, we replicate the framing bias in description-based decisions and find risk indifference in gains and losses in experience-based decisions. Predictions of an Instance-Based Learning model suggest that objective probabilities as well as the number of samples taken are factors that contribute to the lack of framing effect. We test these two factors in Experiment 2 and find no framing effect when a few samples are taken but when large samples are taken, the framing effect appears regardless of the objective probability values. Implications of behavioral results and cognitive modeling are discussed. Copyright © 2015 Cognitive Science Society, Inc.

  8. Intersubjective decision-making for computer-aided forging technology design

    NASA Astrophysics Data System (ADS)

    Kanyukov, S. I.; Konovalov, A. V.; Muizemnek, O. Yu.

    2017-12-01

    We propose a concept of intersubjective decision-making for problems of open-die forging technology design. The intersubjective decisions are chosen from a set of feasible decisions using the fundamentals of the decision-making theory in fuzzy environment according to the Bellman-Zadeh scheme. We consider the formalization of subjective goals and the choice of membership functions for the decisions depending on subjective goals. We study the arrangement of these functions into an intersubjective membership function. The function is constructed for a resulting decision, which is chosen from a set of feasible decisions. The choice of the final intersubjective decision is discussed. All the issues are exemplified by a specific technological problem. The considered concept of solving technological problems under conditions of fuzzy goals allows one to choose the most efficient decisions from a set of feasible ones. These decisions correspond to the stated goals. The concept allows one to reduce human participation in automated design. This concept can be used to develop algorithms and design programs for forging numerous types of forged parts.

  9. Scoring from Contests

    PubMed Central

    Penn, Elizabeth Maggie

    2014-01-01

    This article presents a new model for scoring alternatives from “contest” outcomes. The model is a generalization of the method of paired comparison to accommodate comparisons between arbitrarily sized sets of alternatives in which outcomes are any division of a fixed prize. Our approach is also applicable to contests between varying quantities of alternatives. We prove that under a reasonable condition on the comparability of alternatives, there exists a unique collection of scores that produces accurate estimates of the overall performance of each alternative and satisfies a well-known axiom regarding choice probabilities. We apply the method to several problems in which varying choice sets and continuous outcomes may create problems for standard scoring methods. These problems include measuring centrality in network data and the scoring of political candidates via a “feeling thermometer.” In the latter case, we also use the method to uncover and solve a potential difficulty with common methods of rescaling thermometer data to account for issues of interpersonal comparability. PMID:24748759

  10. Classification of adaptive memetic algorithms: a comparative study.

    PubMed

    Ong, Yew-Soon; Lim, Meng-Hiot; Zhu, Ning; Wong, Kok-Wai

    2006-02-01

    Adaptation of parameters and operators represents one of the recent most important and promising areas of research in evolutionary computations; it is a form of designing self-configuring algorithms that acclimatize to suit the problem in hand. Here, our interests are on a recent breed of hybrid evolutionary algorithms typically known as adaptive memetic algorithms (MAs). One unique feature of adaptive MAs is the choice of local search methods or memes and recent studies have shown that this choice significantly affects the performances of problem searches. In this paper, we present a classification of memes adaptation in adaptive MAs on the basis of the mechanism used and the level of historical knowledge on the memes employed. Then the asymptotic convergence properties of the adaptive MAs considered are analyzed according to the classification. Subsequently, empirical studies on representatives of adaptive MAs for different type-level meme adaptations using continuous benchmark problems indicate that global-level adaptive MAs exhibit better search performances. Finally we conclude with some promising research directions in the area.

  11. Testing process predictions of models of risky choice: a quantitative model comparison approach

    PubMed Central

    Pachur, Thorsten; Hertwig, Ralph; Gigerenzer, Gerd; Brandstätter, Eduard

    2013-01-01

    This article presents a quantitative model comparison contrasting the process predictions of two prominent views on risky choice. One view assumes a trade-off between probabilities and outcomes (or non-linear functions thereof) and the separate evaluation of risky options (expectation models). Another view assumes that risky choice is based on comparative evaluation, limited search, aspiration levels, and the forgoing of trade-offs (heuristic models). We derived quantitative process predictions for a generic expectation model and for a specific heuristic model, namely the priority heuristic (Brandstätter et al., 2006), and tested them in two experiments. The focus was on two key features of the cognitive process: acquisition frequencies (i.e., how frequently individual reasons are looked up) and direction of search (i.e., gamble-wise vs. reason-wise). In Experiment 1, the priority heuristic predicted direction of search better than the expectation model (although neither model predicted the acquisition process perfectly); acquisition frequencies, however, were inconsistent with both models. Additional analyses revealed that these frequencies were primarily a function of what Rubinstein (1988) called “similarity.” In Experiment 2, the quantitative model comparison approach showed that people seemed to rely more on the priority heuristic in difficult problems, but to make more trade-offs in easy problems. This finding suggests that risky choice may be based on a mental toolbox of strategies. PMID:24151472

  12. Optimizing in a complex world: A statistician's role in decision making

    DOE PAGES

    Anderson-Cook, Christine M.

    2016-08-09

    As applied statisticians increasingly participate as active members of problem-solving and decision-making teams, our role continues to evolve. Historically, we may have been seen as those who can help with data collection strategies or answer a specific question from a set of data. Nowadays, we are or strive to be more deeply involved throughout the entire problem-solving process. An emerging role is to provide a set of leading choices from which subject matter experts and managers can choose to make informed decisions. A key to success is to provide vehicles for understanding the trade-offs between candidates and interpreting the meritsmore » of each choice in the context of the decision-makers priorities. To achieve this objective, it is helpful to be able (a) to help subject matter experts identify quantitative criteria that match their priorities, (b) eliminate non-competitive choices through the use of a Pareto front, and (c) provide summary tools from which the trade-offs between alternatives can be quantitatively evaluated and discussed. A structured but flexible process for contributing to team decisions is described for situations when all choices can easily be enumerated as well as when a search algorithm to explore a vast number of potential candidates is required. In conclusion, a collection of diverse examples ranging from model selection, through multiple response optimization, and designing an experiment illustrate the approach.« less

  13. Optimizing in a complex world: A statistician's role in decision making

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson-Cook, Christine M.

    As applied statisticians increasingly participate as active members of problem-solving and decision-making teams, our role continues to evolve. Historically, we may have been seen as those who can help with data collection strategies or answer a specific question from a set of data. Nowadays, we are or strive to be more deeply involved throughout the entire problem-solving process. An emerging role is to provide a set of leading choices from which subject matter experts and managers can choose to make informed decisions. A key to success is to provide vehicles for understanding the trade-offs between candidates and interpreting the meritsmore » of each choice in the context of the decision-makers priorities. To achieve this objective, it is helpful to be able (a) to help subject matter experts identify quantitative criteria that match their priorities, (b) eliminate non-competitive choices through the use of a Pareto front, and (c) provide summary tools from which the trade-offs between alternatives can be quantitatively evaluated and discussed. A structured but flexible process for contributing to team decisions is described for situations when all choices can easily be enumerated as well as when a search algorithm to explore a vast number of potential candidates is required. In conclusion, a collection of diverse examples ranging from model selection, through multiple response optimization, and designing an experiment illustrate the approach.« less

  14. Genetic algorithms and their use in Geophysical Problems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parker, Paul B.

    1999-04-01

    Genetic algorithms (GAs), global optimization methods that mimic Darwinian evolution are well suited to the nonlinear inverse problems of geophysics. A standard genetic algorithm selects the best or ''fittest'' models from a ''population'' and then applies operators such as crossover and mutation in order to combine the most successful characteristics of each model and produce fitter models. More sophisticated operators have been developed, but the standard GA usually provides a robust and efficient search. Although the choice of parameter settings such as crossover and mutation rate may depend largely on the type of problem being solved, numerous results show thatmore » certain parameter settings produce optimal performance for a wide range of problems and difficulties. In particular, a low (about half of the inverse of the population size) mutation rate is crucial for optimal results, but the choice of crossover method and rate do not seem to affect performance appreciably. Optimal efficiency is usually achieved with smaller (< 50) populations. Lastly, tournament selection appears to be the best choice of selection methods due to its simplicity and its autoscaling properties. However, if a proportional selection method is used such as roulette wheel selection, fitness scaling is a necessity, and a high scaling factor (> 2.0) should be used for the best performance. Three case studies are presented in which genetic algorithms are used to invert for crustal parameters. The first is an inversion for basement depth at Yucca mountain using gravity data, the second an inversion for velocity structure in the crust of the south island of New Zealand using receiver functions derived from teleseismic events, and the third is a similar receiver function inversion for crustal velocities beneath the Mendocino Triple Junction region of Northern California. The inversions demonstrate that genetic algorithms are effective in solving problems with reasonably large numbers of free parameters and with computationally expensive objective function calculations. More sophisticated techniques are presented for special problems. Niching and island model algorithms are introduced as methods to find multiple, distinct solutions to the nonunique problems that are typically seen in geophysics. Finally, hybrid algorithms are investigated as a way to improve the efficiency of the standard genetic algorithm.« less

  15. Genetic algorithms and their use in geophysical problems

    NASA Astrophysics Data System (ADS)

    Parker, Paul Bradley

    Genetic algorithms (GAs), global optimization methods that mimic Darwinian evolution are well suited to the nonlinear inverse problems of geophysics. A standard genetic algorithm selects the best or "fittest" models from a "population" and then applies operators such as crossover and mutation in order to combine the most successful characteristics of each model and produce fitter models. More sophisticated operators have been developed, but the standard GA usually provides a robust and efficient search. Although the choice of parameter settings such as crossover and mutation rate may depend largely on the type of problem being solved, numerous results show that certain parameter settings produce optimal performance for a wide range of problems and difficulties. In particular, a low (about half of the inverse of the population size) mutation rate is crucial for optimal results, but the choice of crossover method and rate do not seem to affect performance appreciably. Also, optimal efficiency is usually achieved with smaller (<50) populations. Lastly, tournament selection appears to be the best choice of selection methods due to its simplicity and its autoscaling properties. However, if a proportional selection method is used such as roulette wheel selection, fitness scaling is a necessity, and a high scaling factor (>2.0) should be used for the best performance. Three case studies are presented in which genetic algorithms are used to invert for crustal parameters. The first is an inversion for basement depth at Yucca mountain using gravity data, the second an inversion for velocity structure in the crust of the south island of New Zealand using receiver functions derived from teleseismic events, and the third is a similar receiver function inversion for crustal velocities beneath the Mendocino Triple Junction region of Northern California. The inversions demonstrate that genetic algorithms are effective in solving problems with reasonably large numbers of free parameters and with computationally expensive objective function calculations. More sophisticated techniques are presented for special problems. Niching and island model algorithms are introduced as methods to find multiple, distinct solutions to the nonunique problems that are typically seen in geophysics. Finally, hybrid algorithms are investigated as a way to improve the efficiency of the standard genetic algorithm.

  16. Two Legendre-Dual-Petrov-Galerkin Algorithms for Solving the Integrated Forms of High Odd-Order Boundary Value Problems

    PubMed Central

    Abd-Elhameed, Waleed M.; Doha, Eid H.; Bassuony, Mahmoud A.

    2014-01-01

    Two numerical algorithms based on dual-Petrov-Galerkin method are developed for solving the integrated forms of high odd-order boundary value problems (BVPs) governed by homogeneous and nonhomogeneous boundary conditions. Two different choices of trial functions and test functions which satisfy the underlying boundary conditions of the differential equations and the dual boundary conditions are used for this purpose. These choices lead to linear systems with specially structured matrices that can be efficiently inverted, hence greatly reducing the cost. The various matrix systems resulting from these discretizations are carefully investigated, especially their complexities and their condition numbers. Numerical results are given to illustrate the efficiency of the proposed algorithms, and some comparisons with some other methods are made. PMID:24616620

  17. Design of an advanced flight planning system

    NASA Technical Reports Server (NTRS)

    Sorensen, J. A.; Goka, T.

    1985-01-01

    The demand for both fuel conservation and four-dimensional traffic management require that the preflight planning process be designed to account for advances in airborne flight management and weather forecasting. The steps and issues in designing such an advanced flight planning system are presented. Focus is placed on the different optimization options for generating the three-dimensional reference path. For the cruise phase, one can use predefined jet routes, direct routes based on a network of evenly spaced grid points, or a network where the grid points are existing navaid locations. Each choice has its own problem in determining an optimum solution. Finding the reference path is further complicated by choice of cruise altitude levels, use of a time-varying weather field, and requiring a fixed time-of-arrival (four-dimensional problem).

  18. Convergence of a sequence of dual variables at the solution of a completely degenerate problem of linear programming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dikin, I.

    1994-12-31

    We survey results about the convergence of the primal affine scaling method at solutions of a completely degenerate problem of linear programming. Moreover we are studying the case when a next approximation is on the boundary of the affine scaling ellipsoid. Convergence of successive approximation to an interior point u of the solution for the dual problem is proved. Coordinates of the vector u are determined only by the input data of the problem; they do not depend of the choice of the starting point.

  19. Species Choice for Comparative Genomics: Being Greedy Works

    PubMed Central

    Pardi, Fabio; Goldman, Nick

    2005-01-01

    Several projects investigating genetic function and evolution through sequencing and comparison of multiple genomes are now underway. These projects consume many resources, and appropriate planning should be devoted to choosing which species to sequence, potentially involving cooperation among different sequencing centres. A widely discussed criterion for species choice is the maximisation of evolutionary divergence. Our mathematical formalization of this problem surprisingly shows that the best long-term cooperative strategy coincides with the seemingly short-term “greedy” strategy of always choosing the next best single species. Other criteria influencing species choice, such as medical relevance or sequencing costs, can also be accommodated in our approach, suggesting our results' broad relevance in scientific policy decisions. PMID:16327885

  20. Ethical problems in radiology: radiological consumerism.

    PubMed

    Magnavita, N; Bergamaschi, A

    2009-10-01

    One of the causes of the increasing request for radiological examinations occurring in all economically developed countries is the active role played by the patient-consumer. Consumerism places the radiologist in an ethical dilemma, between the principle of autonomy on the one hand and the ethical principles of beneficence, nonmaleficence and justice on the other. The choice made by radiologists in moral dilemmas is inspired by an adherence to moral principles, which in Italy and elsewhere refer to the Judaeo-Christian tradition or to neo-Darwinian relativism. Whatever the choice, the radiologist is bound to adhere to that choice and to provide the patient with all the relevant information regarding his or her state of health.

  1. Supervised Clustering Based on DPClusO: Prediction of Plant-Disease Relations Using Jamu Formulas of KNApSAcK Database

    PubMed Central

    Husnawati, Husnawati; Afendi, Farit Mochamad; Darusman, Latifah K.; Altaf-Ul-Amin, Md.; Sato, Tetsuo; Ono, Naoaki; Sugiura, Tadao; Kanaya, Shigehiko

    2014-01-01

    Indonesia has the largest medicinal plant species in the world and these plants are used as Jamu medicines. Jamu medicines are popular traditional medicines from Indonesia and we need to systemize the formulation of Jamu and develop basic scientific principles of Jamu to meet the requirement of Indonesian Healthcare System. We propose a new approach to predict the relation between plant and disease using network analysis and supervised clustering. At the preliminary step, we assigned 3138 Jamu formulas to 116 diseases of International Classification of Diseases (ver. 10) which belong to 18 classes of disease from National Center for Biotechnology Information. The correlation measures between Jamu pairs were determined based on their ingredient similarity. Networks are constructed and analyzed by selecting highly correlated Jamu pairs. Clusters were then generated by using the network clustering algorithm DPClusO. By using matching score of a cluster, the dominant disease and high frequency plant associated to the cluster are determined. The plant to disease relations predicted by our method were evaluated in the context of previously published results and were found to produce around 90% successful predictions. PMID:24804251

  2. Switched Systems and Motion Coordination: Combinatorial Challenges

    NASA Technical Reports Server (NTRS)

    Sadovsky, Alexander V.

    2016-01-01

    Problems of routing commercial air traffic in a terminal airspace encounter different constraints: separation assurance, aircraft performance limitations, regulations. The general setting of these problems is that of a switched control system. Such a system combines the differentiable motion of the aircraft with the combinatorial choices of choosing precedence when traffic routes merge and choosing branches when the routes diverge. This presentation gives an overview of the problem, the ATM context, related literature, and directions for future research.

  3. Integrated multi-choice goal programming and multi-segment goal programming for supplier selection considering imperfect-quality and price-quantity discounts in a multiple sourcing environment

    NASA Astrophysics Data System (ADS)

    Chang, Ching-Ter; Chen, Huang-Mu; Zhuang, Zheng-Yun

    2014-05-01

    Supplier selection (SS) is a multi-criteria and multi-objective problem, in which multi-segment (e.g. imperfect-quality discount (IQD) and price-quantity discount (PQD)) and multi-aspiration level problems may be significantly important; however, little attention had been given to dealing with both of them simultaneously in the past. This study proposes a model for integrating multi-choice goal programming and multi-segment goal programming to solve the above-mentioned problems by providing the following main contributions: (1) it allows decision-makers to set multiple aspiration levels on the right-hand side of each goal to suit real-world situations, (2) the PQD and IQD conditions are considered in the proposed model simultaneously and (3) the proposed model can solve a SS problem with n suppliers where each supplier offers m IQD with r PQD intervals, where only ? extra binary variables are required. The usefulness of the proposed model is explained using a real case. The results indicate that the proposed model not only can deal with a SS problem with multi-segment and multi-aspiration levels, but also can help the decision-maker to find the appropriate order quantities for each supplier by considering cost, quality and delivery.

  4. Applications of decision analysis and related techniques to industrial engineering problems at KSC

    NASA Technical Reports Server (NTRS)

    Evans, Gerald W.

    1995-01-01

    This report provides: (1) a discussion of the origination of decision analysis problems (well-structured problems) from ill-structured problems; (2) a review of the various methodologies and software packages for decision analysis and related problem areas; (3) a discussion of how the characteristics of a decision analysis problem affect the choice of modeling methodologies, thus providing a guide as to when to choose a particular methodology; and (4) examples of applications of decision analysis to particular problems encountered by the IE Group at KSC. With respect to the specific applications at KSC, particular emphasis is placed on the use of the Demos software package (Lumina Decision Systems, 1993).

  5. Social value and individual choice: The value of a choice-based decision-making process in a collectively funded health system.

    PubMed

    Espinoza, Manuel Antonio; Manca, Andrea; Claxton, Karl; Sculpher, Mark

    2018-02-01

    Evidence about cost-effectiveness is increasingly being used to inform decisions about the funding of new technologies that are usually implemented as guidelines from centralized decision-making bodies. However, there is also an increasing recognition for the role of patients in determining their preferred treatment option. This paper presents a method to estimate the value of implementing a choice-based decision process using the cost-effectiveness analysis toolbox. This value is estimated for 3 alternative scenarios. First, it compares centralized decisions, based on population average cost-effectiveness, against a decision process based on patient choice. Second, it compares centralized decision based on patients' subgroups versus an individual choice-based decision process. Third, it compares a centralized process based on average cost-effectiveness against a choice-based process where patients choose according to a different measure of outcome to that used by the centralized decision maker. The methods are applied to a case study for the management of acute coronary syndrome. It is concluded that implementing a choice-based process of treatment allocation may be an option in collectively funded health systems. However, its value will depend on the specific health problem and the social values considered relevant to the health system. Copyright © 2017 John Wiley & Sons, Ltd.

  6. Testing Transitivity of Preferences on Two-Alternative Forced Choice Data

    PubMed Central

    Regenwetter, Michel; Dana, Jason; Davis-Stober, Clintin P.

    2010-01-01

    As Duncan Luce and other prominent scholars have pointed out on several occasions, testing algebraic models against empirical data raises difficult conceptual, mathematical, and statistical challenges. Empirical data often result from statistical sampling processes, whereas algebraic theories are nonprobabilistic. Many probabilistic specifications lead to statistical boundary problems and are subject to nontrivial order constrained statistical inference. The present paper discusses Luce's challenge for a particularly prominent axiom: Transitivity. The axiom of transitivity is a central component in many algebraic theories of preference and choice. We offer the currently most complete solution to the challenge in the case of transitivity of binary preference on the theory side and two-alternative forced choice on the empirical side, explicitly for up to five, and implicitly for up to seven, choice alternatives. We also discuss the relationship between our proposed solution and weak stochastic transitivity. We recommend to abandon the latter as a model of transitive individual preferences. PMID:21833217

  7. The Ethics of Organ Donor Registration Policies: Nudges and Respect for Autonomy.

    PubMed

    MacKay, Douglas; Robinson, Alexandra

    2016-11-01

    Governments must determine the legal procedures by which their residents are registered, or can register, as organ donors. Provided that governments recognize that people have a right to determine what happens to their organs after they die, there are four feasible options to choose from: opt-in, opt-out, mandated active choice, and voluntary active choice. We investigate the ethics of these policies' use of nudges to affect organ donor registration rates. We argue that the use of nudges in this context is morally problematic. It is disrespectful of people's autonomy to take advantage of their cognitive biases since doing so involves bypassing, not engaging, their rational capacities. We conclude that while mandated active choice policies are not problem free-they are coercive, after all-voluntary active choice, opt-in, and opt-out policies are potentially less respectful of people's autonomy since their use of nudges could significantly affect people's decision making.

  8. The mandatory health insurance system in Chile: explaining the choice between public and private insurance.

    PubMed

    Sapelli, C; Torche, A

    2001-06-01

    In Chile, dependent workers and retirees are mandated by law to purchase health insurance, and can choose between private and public health insurance. This paper studies the determinants of the choice of health insurance. Earnings are generally considered the key factor in this choice, and we confirm this, but find that other factors are also important. It is particularly interesting to analyze how the individual's characteristics interact with the design of the system to influence choice. Worse health, as signaled by age or sex (e.g., older people or women in reproductive ages), results in adverse selection against the public health insurance system. This is due to the lack of risk adjustment of the public health insurance's premium. Hence, Chile's risk selection problem is, at least in part, due to the design of the Chilean public insurance system.

  9. Evaluating The Influence of Postsession Reinforcement on Choice of Reinforcers

    PubMed Central

    Kodak, Tiffany; Lerman, Dorothea C; Call, Nathan

    2007-01-01

    Factors that influence reinforcer choice have been examined in a number of applied studies (e.g., Neef, Mace, Shea, & Shade, 1992; Shore, Iwata, DeLeon, Kahng, & Smith, 1997; Tustin, 1994). However, no applied studies have evaluated the effects of postsession reinforcement on choice between concurrently available reinforcers, even though basic findings indicate that this is an important factor to consider (Hursh, 1978; Zeiler, 1999). In this bridge investigation, we evaluated the influence of postsession reinforcement on choice of two food items when task responding was reinforced on progressive-ratio schedules. Participants were 3 children who had been diagnosed with developmental disabilities. Results indicated that response allocation shifted from one food item to the other food item under thinner schedules of reinforcement when no postsession reinforcement was provided. These findings suggest that the efficacy of instructional programs or treatments for problem behavior may be improved by restricting reinforcers outside treatment sessions. PMID:17970264

  10. Evaluating the influence of postsession reinforcement on choice of reinforcers.

    PubMed

    Kodak, Tiffany; Lerman, Dorothea C; Call, Nathan

    2007-01-01

    Factors that influence reinforcer choice have been examined in a number of applied studies (e.g., Neef, Mace, Shea, & Shade, 1992; Shore, Iwata, DeLeon, Kahng, & Smith, 1997; Tustin, 1994). However, no applied studies have evaluated the effects of postsession reinforcement on choice between concurrently available reinforcers, even though basic findings indicate that this is an important factor to consider (Hursh, 1978; Zeiler, 1999). In this bridge investigation, we evaluated the influence of postsession reinforcement on choice of two food items when task responding was reinforced on progressive-ratio schedules. Participants were 3 children who had been diagnosed with developmental disabilities. Results indicated that response allocation shifted from one food item to the other food item under thinner schedules of reinforcement when no postsession reinforcement was provided. These findings suggest that the efficacy of instructional programs or treatments for problem behavior may be improved by restricting reinforcers outside treatment sessions.

  11. Problems in Comprehensive Ambulatory Health Care for High-Risk Adolescents.

    ERIC Educational Resources Information Center

    Fielding, Jon E., Ed.

    This volume contains 21 articles on aspects held to be important for delivering comprehensive health care to young adults who are at higher than average risk levels for a number of health and health-related problems; choice of topics for the articles is based on experience gained in directing the health program for the Job Corps. Most of the…

  12. The Effects of Experience Grouping on Achievement, Problem-Solving Discourse, and Satisfaction in Professional Technical Training

    ERIC Educational Resources Information Center

    Mulcahy, Robert Sean

    2010-01-01

    Learners inevitably enter adult technical training classrooms--indeed, in all classrooms--with different levels of expertise on the subject matter. When the diversity of expertise is wide and the course makes use of small group problem solving, instructors have a choice about how to group learners: they may distribute learners with greater…

  13. Wise Choices? The Economics Discourse of a High School Economics and Personal Finance Course

    ERIC Educational Resources Information Center

    Sober, Tamara Leigh

    2017-01-01

    Today's high school students will face a host of economic problems such as the demise of the social safety net, mounting college student debt, and costly health care plans, as stated in the rationale for financial literacy provided by the Council for Economic Education's National Standards for Financial Literacy. These problems are compounded by…

  14. Modeling the Problem-Based Learning Preferences of McMaster University Undergraduate Medical Students Using a Discrete Choice Conjoint Experiment

    ERIC Educational Resources Information Center

    Cunningham, Charles E.; Deal, Ken; Neville, Alan; Rimas, Heather; Lohfeld, Lynne

    2006-01-01

    Objectives: To use methods from the field of marketing research to involve students in the redesign of McMaster University's small group, problem-based undergraduate medical education program. Methods: We used themes from a focus group conducted in an electronic decision support lab to compose 14 four-level educational attributes. Undergraduate…

  15. Force, Velocity, and Work: The Effects of Different Contexts on Students' Understanding of Vector Concepts Using Isomorphic Problems

    ERIC Educational Resources Information Center

    Barniol, Pablo; Zavala, Genaro

    2014-01-01

    In this article we compare students' understanding of vector concepts in problems with no physical context, and with three mechanics contexts: force, velocity, and work. Based on our "Test of Understanding of Vectors," a multiple-choice test presented elsewhere, we designed two isomorphic shorter versions of 12 items each: a test with no…

  16. Problem-Based Labs and Group Projects in an Introductory University Physics Course

    ERIC Educational Resources Information Center

    Kohnle, Antje; Brown, C. Tom A.; Rae, Cameron F.; Sinclair, Bruce D.

    2012-01-01

    This article describes problem-based labs and analytical and computational project work we have been running at the University of St Andrews in an introductory physics course since 2008/2009. We have found the choice of topics, scaffolding of the process, timing in the year and facilitator guidance decisive for the success of these activities.…

  17. Consumer protection and managed care: the need for organized consumers.

    PubMed

    Rodwin, M A

    1996-01-01

    Despite its many advantages, managed care creates new problems for consumers. Activists have proposed four types of remedies: (1) increased information and choice; (2) standards for services and marketing; (3) administrative oversight; and (4) procedural due process for complaints. Each approach offers some benefits, but they are insufficient to cope with consumer problems. What is lacking is effective, organized consumer advocacy.

  18. Factors Related to Problem Solving by College Students in Developmental Algebra.

    ERIC Educational Resources Information Center

    Schonberger, Ann K.

    A study was conducted to contrast the characteristics of three groups of college students who completed a developmental algebra course at the University of Maine at Orono during 1980-81. On the basis of a two-part final examination, involving a multiple-choice test of algebraic concepts and skills and a free-response test of problem-solving…

  19. A Minimum-Residual Finite Element Method for the Convection-Diffusion Equation

    DTIC Science & Technology

    2013-05-01

    4p . We note that these two choices of discretization for V are not mutually exclusive, and that novel choices for Vh are likely the key to yielding...the inside with the positive- definite operator A, which is precisely the discrete system that arises under the optimal test function framework of DPG...converts the fine-scale problem into a symmetric-positive definite one, allowing for a well-behaved subgrid model of fine scale behavior. We begin again

  20. Choices between positive and negative reinforcement during treatment for escape-maintained behavior.

    PubMed

    DeLeon, I G; Neidert, P L; Anders, B M; Rodriguez-Catter, V

    2001-01-01

    Positive reinforcement was more effective than negative reinforcement in promoting compliance and reducing escape-maintained problem behavior for a child with autism. Escape extinction was then added while the child was given a choice between positive or negative reinforcement for compliance and the reinforcement schedule was thinned. When the reinforcement requirement reached 10 consecutive tasks, the treatment effects became inconsistent and reinforcer selection shifted from a strong preference for positive reinforcement to an unstable selection pattern.

  1. Public goods and procreation.

    PubMed

    Anomaly, Jonathan

    2014-01-01

    Procreation is the ultimate public goods problem. Each new child affects the welfare of many other people, and some (but not all) children produce uncompensated value that future people will enjoy. This essay addresses challenges that arise if we think of procreation and parenting as public goods. These include whether individual choices are likely to lead to a socially desirable outcome, and whether changes in laws, social norms, or access to genetic engineering and embryo selection might improve the aggregate outcome of our reproductive choices.

  2. Environmental Factors in the Choice of EGMs: A Discrete Choice Experiment.

    PubMed

    Rockloff, Matthew J; Moskovsky, Neda; Thorne, Hannah; Browne, Matthew; Bryden, Gabrielle M

    2017-09-01

    EGMs are a form of entertainment, and the gambling environment is an important contributor to the overall experience. Logically, to select a play-environment, EGM gamblers must choose the platform through which to access the EGM (e.g., internet, mobile application or land-based venue), a particular provider (e.g., specific website, app vendor or branded casino), and the game itself (e.g., based on graphical theme or bonus features; Thorne et al. in J Gambl Stud, 2016. doi: 10.1007/s10899-016-9601-2 ). A discrete choice experiment was conducted to identify the features of the platform, provider and game that are most strongly preferred by EGM gamblers. Participants were 245 EGM gamblers from clubs in Victoria, Australia and 7516 EGM gamblers from an Australian online panel. Results indicate that the ideal environment for the average gambler consists of: gambling at a club that is close to home; with a group of friends; in a relatively quiet place that has air conditioning, cheap food and a large space to play in; on a classic game with quality animations and small bet sizes; where you feel safe and secure; and where there is a wide variety of other games to play when you are done. Segmenting these results by problem-gambler status highlights important differences in preferences between problem and non-problem gamblers. Problem gamblers are less likely to give weight to the company they share and have a preference for larger venues. Using a powerful paradigm from marketing research, the present study was able to determine the relative value of different features of the EGM gambling environment, and also contributes important insight towards what constitutes a safer environment for recreational play.

  3. "You have to be careful who you talk to and what you say …" - on psychosis and making rational choices.

    PubMed

    Topor, Alain; Di Girolamo, Simonetta

    2010-12-01

    People who have been diagnosed with schizophrenia are regarded as being no longer capable of making rational choices. Fifteen users with psychosis diagnosis participated to 10 focus group sessions about different aspects of everyday life. The discussions were tape recorded and the transcript analyzed using a grounded theory inspired methodology. A core category that emerged was making choices in crises situations. Users have to choose whether or not they want help, to whom to turn for help, and how to describe their problems so as to get the kind of help they seek. The choices were based on past experiences in connection with the choices available. They were constantly making quality judgements of the care workers they came into contact with. Experiencing a sense of comradeship emerged as a vital criterion. The ability to make rational choices often existed parallel with hallucinations and delusions. This ability could form the basis for a true collaboration between users and professionals. The findings of this study indicate that such collaboration is possible, but that it requires a reassessment of our traditional knowledge base.

  4. Effects of 7-day continuous d-amphetamine, methylphenidate, and cocaine treatment on choice between methamphetamine and food in male rhesus monkeys*

    PubMed Central

    Schwienteck, Kathryn L.; Banks, Matthew L.

    2015-01-01

    Background Methamphetamine addiction is a significant public health problem for which no Food and Drug Administration-approved pharmacotherapies exist. Preclinical drug vs. food choice procedures have been predictive of clinical medication efficacy in the treatment of opioid and cocaine addiction. Whether preclinical choice procedures are predictive of candidate medication effects for other abused drugs, such as methamphetamine, remains unclear. The present study aim was to determine continuous 7-day treatment effects with the monoamine releaser d-amphetamine and the monoamine uptake inhibitor methylphenidate on methamphetamine vs. food choice.In addition, 7-day cocaine treatment effects were also examined. Methods Behavior was maintained under a concurrent schedule of food delivery (1-g pellets, fixed-ratio 100 schedule) and methamphetamine injections (0-0.32 mg/kg/injection, fixed-ratio 10 schedule) in male rhesus monkeys (n=4). Methamphetamine choice dose-effect functions were determined daily before and during 7-day periods of continuous intravenous treatment with d-amphetamine (0.01-0.1 mg/kg/h), methylphenidate (0.032-0.32 mg/kg/h), or cocaine (0.1-0.32 mg/kg/h). Results During saline treatment, increasing methamphetamine doses resulted in a corresponding increase in methamphetamine vs. food choice. Continuous 7-day treatments with d-amphetamine, methylphenidate or cocaine did not significantly attenuate methamphetamine vs. food choice up to doses that decreased rates of operant responding. However, 0.1 mg/kg/h d-amphetamine did eliminate methamphetamine choice in two monkeys. Conclusions The present subchronic treatment resultssupport the utility of preclinical methamphetamine choice to evaluate candidate medications for methamphetamine addiction. Furthermore, these results confirm and extend previous results demonstrating differential pharmacological mechanisms between cocaine choice and methamphetamine choice. PMID:26361713

  5. Effects of 7-day continuous D-amphetamine, methylphenidate, and cocaine treatment on choice between methamphetamine and food in male rhesus monkeys.

    PubMed

    Schwienteck, Kathryn L; Banks, Matthew L

    2015-10-01

    Methamphetamine addiction is a significant public health problem for which no Food and Drug Administration-approved pharmacotherapies exist. Preclinical drug vs. food choice procedures have been predictive of clinical medication efficacy in the treatment of opioid and cocaine addiction. Whether preclinical choice procedures are predictive of candidate medication effects for other abused drugs, such as methamphetamine, remains unclear. The present study aim was to determine continuous 7-day treatment effects with the monoamine releaser d-amphetamine and the monoamine uptake inhibitor methylphenidate on methamphetamine vs. food choice. In addition, 7-day cocaine treatment effects were also examined. Behavior was maintained under a concurrent schedule of food delivery (1-g pellets, fixed-ratio 100 schedule) and methamphetamine injections (0-0.32mg/kg/injection, fixed-ratio 10 schedule) in male rhesus monkeys (n=4). Methamphetamine choice dose-effect functions were determined daily before and during 7-day periods of continuous intravenous treatment with d-amphetamine (0.01-0.1mg/kg/h), methylphenidate (0.032-0.32mg/kg/h), or cocaine (0.1-0.32mg/kg/h). During saline treatment, increasing methamphetamine doses resulted in a corresponding increase in methamphetamine vs. food choice. Continuous 7-day treatments with d-amphetamine, methylphenidate or cocaine did not significantly attenuate methamphetamine vs. food choice up to doses that decreased rates of operant responding. However, 0.1mg/kg/h d-amphetamine did eliminate methamphetamine choice in two monkeys. The present subchronic treatment results support the utility of preclinical methamphetamine choice to evaluate candidate medications for methamphetamine addiction. Furthermore, these results confirm and extend previous results demonstrating differential pharmacological mechanisms between cocaine choice and methamphetamine choice. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. A Unified Information System for Appropriate Technology.

    ERIC Educational Resources Information Center

    Unamboowe, Ira

    1980-01-01

    Considers problems and solutions for transfer of technological information for developing nations. Imbalances created by industrial growth have brought the concept of choice of technologies to the forefront of national objectives. (RAA)

  7. Psychosocial Problems of Job Relocation: Preventive Roles in Industry.

    ERIC Educational Resources Information Center

    Anderson, Charlene; Stark, Carolyn

    1988-01-01

    Discusses effects of employment-related geographic relocation, such as stress-related diseases, in relation to nontraditional family systems. Advocates employee assistance programs as method of choice for service intervention. (Author/NB)

  8. Choices, choices: the application of multi-criteria decision analysis to a food safety decision-making problem.

    PubMed

    Fazil, A; Rajic, A; Sanchez, J; McEwen, S

    2008-11-01

    In the food safety arena, the decision-making process can be especially difficult. Decision makers are often faced with social and fiscal pressures when attempting to identify an appropriate balance among several choices. Concurrently, policy and decision makers in microbial food safety are under increasing pressure to demonstrate that their policies and decisions are made using transparent and accountable processes. In this article, we present a multi-criteria decision analysis approach that can be used to address the problem of trying to select a food safety intervention while balancing various criteria. Criteria that are important when selecting an intervention were determined, as a result of an expert consultation, to include effectiveness, cost, weight of evidence, and practicality associated with the interventions. The multi-criteria decision analysis approach we present is able to consider these criteria and arrive at a ranking of interventions. It can also provide a clear justification for the ranking as well as demonstrate to stakeholders, through a scenario analysis approach, how to potentially converge toward common ground. While this article focuses on the problem of selecting food safety interventions, the range of applications in the food safety arena is truly diverse and can be a significant tool in assisting decisions that need to be coherent, transparent, and justifiable. Most importantly, it is a significant contributor when there is a need to strike a fine balance between various potentially competing alternatives and/or stakeholder groups.

  9. Using a Portfolio of Algorithms for Planning and Scheduling

    NASA Technical Reports Server (NTRS)

    Sherwood, Robert; Knight, Russell; Rabideau, Gregg; Chien, Steve; Tran, Daniel; Engelhardt, Barbara

    2003-01-01

    The Automated Scheduling and Planning Environment (ASPEN) software system, aspects of which have been reported in several previous NASA Tech Briefs articles, includes a subsystem that utilizes a portfolio of heuristic algorithms that work synergistically to solve problems. The nature of the synergy of the specific algorithms is that their likelihoods of success are negatively correlated: that is, when a combination of them is used to solve a problem, the probability that at least one of them will succeed is greater than the sum of probabilities of success of the individual algorithms operating independently of each other. In ASPEN, the portfolio of algorithms is used in a planning process of the iterative repair type, in which conflicts are detected and addressed one at a time until either no conflicts exist or a user-defined time limit has been exceeded. At each choice point (e.g., selection of conflict; selection of method of resolution of conflict; or choice of move, addition, or deletion) ASPEN makes a stochastic choice of a combination of algorithms from the portfolio. This approach makes it possible for the search to escape from looping and from solutions that are locally but not globally optimum.

  10. Repeated causal decision making.

    PubMed

    Hagmayer, York; Meder, Björn

    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 such situations and how they use their knowledge to adapt to changes in the decision context. Our studies show that decision makers' behavior is strongly contingent on their causal beliefs and that people exploit their causal knowledge to assess the consequences of changes in the decision problem. A high consistency between hypotheses about causal structure, causally expected values, and actual choices was observed. The experiments show that (a) existing causal hypotheses guide the interpretation of decision feedback, (b) consequences of decisions are used to revise existing causal beliefs, and (c) decision makers use the experienced feedback to induce a causal model of the choice situation even when they have no initial causal hypotheses, which (d) enables them to adapt their choices to changes of the decision problem. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  11. Contraceptive implants: long acting and provider dependent contraception raises concerns about freedom of choice.

    PubMed

    Thompson, M S

    1996-11-30

    David Bromham's editorial on contraceptive implants ignores the wider issues to voice concern that trial by media could limit contraceptive choice by jeopardising research into new methods. However, it is more beneficial to the public for points of conflict to be debated openly. Furthermore, the impetus for research into new contraceptive technology is driven by profit and political motives and is only marginally affected by the media. Implanted contraceptives may increase the choice of contraceptive methods, but they put control of fertility increasingly into the hands of the medical profession. Herein lies their greatest problem: their potential to increase providers' control over clients' choice. There is the danger that certain groups of women may be targeted for their use: in the United States the coercive use of Norplant for mothers receiving welfare benefit has been suggested. Long acting contraceptives are a contraceptive of choice only when they are available without pressure, as part of a wider menu; when instant removal on request is guaranteed; and when there is an open and free flow of information and opinions between users, health professionals, and special interest groups.

  12. Objective Physiological Measurements but Not Subjective Reports Moderate the Effect of Hunger on Choice Behavior

    PubMed Central

    Shabat-Simon, Maytal; Shuster, Anastasia; Sela, Tal; Levy, Dino J.

    2018-01-01

    Hunger is a powerful driver of human behavior, and is therefore of great interest to the study of psychology, economics, and consumer behavior. Assessing hunger levels in experiments is often biased, when using self-report methods, or complex, when using blood tests. We propose a novel way of objectively measuring subjects’ levels of hunger by identifying levels of alpha-amylase (AA) enzyme in their saliva samples. We used this measure to uncover the effect of hunger on different types of choice behaviors. We found that hunger increases risk-seeking behavior in a lottery-choice task, modifies levels of vindictiveness in a social decision-making task, but does not have a detectible effect on economic inconsistency in a budget-set choice task. Importantly, these findings were moderated by AA levels and not by self-report measures. We demonstrate the effects hunger has on choice behavior and the problematic nature of subjective measures of physiological states, and propose to use reliable and valid biologically based methods to overcome these problems. PMID:29875715

  13. Engaging adolescent girls in transactional sex through compensated dating.

    PubMed

    Cheung, Chau-Kiu; Jia, Xinshan; Li, Jessica Chi-Mei; Lee, Tak-Yan

    2016-10-01

    Transactional sex through so-called compensated dating in adolescent girls is a problem in need of public concern. Compensated dating typically involves the use of information communication technology to advertise, search, bargain, and eventually arrange for transactional sex. The technology enables the sexual partners to maintain privacy and secrecy in transactional sex. Such secrecy necessitates the girls' disclosure about their life experiences in order to address the concern. The disclosure is the focus of the present qualitative study of 27 girls practicing the dating in Hong Kong, China. Based on the disclosure, the study presents a grounded theory that epitomizes engagement in compensated dating by referential choice. Such a referential choice theory unravels that choice with reference to the family push and social norms sustains the engagement. Meanwhile, the choice rests on expectancy and reinforcement from experiential learning about compensated dating. The theory thus implies ways to undercut the engagement through diverting the referential choice of the dating. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  14. Intellectual system for images restoration

    NASA Astrophysics Data System (ADS)

    Mardare, Igor

    2005-02-01

    Intelligence systems on basis of artificial neural networks and associative memory allow to solve effectively problems of recognition and restoration of images. However, within analytical technologies there are no dominating approaches of deciding of intellectual problems. Choice of the best technology depends on nature of problem, features of objects, volume of represented information about the object, number of classes of objects, etc. It is required to determine opportunities, preconditions and field of application of neural networks and associative memory for decision of problem of restoration of images and to use their supplementary benefits for further development of intelligence systems.

  15. How Children's Justifications of the "Best Thing to Do" in Peer Conflicts Relate to Their Emotional and Behavioral Problems in Early Elementary School

    ERIC Educational Resources Information Center

    Leadbeater, Bonnie J.; Ohan, Jeneva L.; Hoglund, Wendy L.

    2006-01-01

    In this three-year longitudinal study, children were asked to choose the "best" strategy for dealing with hypothetical peer provocations and to justify "why" that was their choice at the end of first, second, and third grades. Teachers and parents also rated children's emotional and behavioral problems. Children's justifications were subjected to…

  16. Global Environmental Problems: Implications for U.S. Policy. Tenth Edition. Teacher Resource Book [and Student Text]. Public Policy Debate in the Classroom. Choices for the 21st Century.

    ERIC Educational Resources Information Center

    Fox, Sarah Cleveland

    Scientists have increasingly focused attention on far-reaching environmental threats, such as climate change, ozone depletion, and deforestation, that transcend national boundaries. A new concept, global environmental problems, has entered the public arena, particularly in the area of foreign policy and economic matters. This unit explores the…

  17. Designing Adaptive Instructional Environments: Insights from Empirical Evidence

    DTIC Science & Technology

    2011-10-01

    theorems. Cohen’s f effect size for pretest to posttest gain, averaged across different problems = 0.46. 7 Basis for Adaptation Ability of...problems and took a posttest . Measures of Learning 26-item multiple choice pretest and posttest . Effect size on posttest scores as measured by...solving algebraic equations. Measures of Learning Pretest and posttest using rapid diagnostic testing procedure: Student had to provide their

  18. Impulsivity and Gambling Type Among Treatment-Seeking Disordered Gamblers: An Explorative Study.

    PubMed

    Lutri, Vittorio; Soldini, Emiliano; Ronzitti, Silvia; Smith, Neil; Clerici, Massimo; Blaszczynski, Alex; Bowden-Jones, Henrietta

    2018-03-03

    Several studies have found that certain traits of impulsivity are associated with gambling disorder, and influence its severity. Furthermore, it has been suggested that some forms of gambling, particularly electronic gambling machines, are particularly widespread among pathological gamblers. In the present, exploratory study, we aim to clarify the role played by impulsivity in influencing the choice of specific gambling activities, by examining the relation between individual dimensions of impulsivity, and the choice of specific gambling activities in a clinical population. 100 consecutively admitted pathological gamblers at the National Problem Gambling Clinic in London (UK) in 2014 were administered the UPPS-P and BIS-11 impulsivity questionnaires, the Problem Gambling Severity Index, and underwent a structured interview concerning their gambling activities in the month and year prior to assessment. The correlation between individual gambling activities and impulsivity dimensions was analyzed both at a bivariate level, and using logistic regression. We found a significant correlation between Negative Urgency, Motor impulsivity and low-stakes machine gambling on multivariate analysis. Negative urgency (i.e. the tendency to act impulsively in response to negative affect), and Motor impulsivity (a tendency to rash action and restlessness) might be mediating factors in the choice of electronic gambling machines, particularly among patients whose gambling is escape-oriented. Structural and situational characteristics of gambling machines, particularly the widespread availability of low-stakes-rather than high-stakes-gaming machines, might concur to the choice of this form of gambling among individuals who present higher negative urgency and restlessness.

  19. Exact solutions for the collaborative pickup and delivery problem.

    PubMed

    Gansterer, Margaretha; Hartl, Richard F; Salzmann, Philipp E H

    2018-01-01

    In this study we investigate the decision problem of a central authority in pickup and delivery carrier collaborations. Customer requests are to be redistributed among participants, such that the total cost is minimized. We formulate the problem as multi-depot traveling salesman problem with pickups and deliveries. We apply three well-established exact solution approaches and compare their performance in terms of computational time. To avoid unrealistic solutions with unevenly distributed workload, we extend the problem by introducing minimum workload constraints. Our computational results show that, while for the original problem Benders decomposition is the method of choice, for the newly formulated problem this method is clearly dominated by the proposed column generation approach. The obtained results can be used as benchmarks for decentralized mechanisms in collaborative pickup and delivery problems.

  20. On Sound Footing: The Health of Your Feet

    MedlinePlus

    ... on your feet. Poorly fitting shoes and other footwear are common causes of foot problems as well. ... Choices Foot Health Tips Use appropriate, well-fitting footwear. Wear clean socks. Keep your feet clean. Exercise ...

  1. CDC Vital Signs: Reducing Sodium in Children's Diets

    MedlinePlus

    ... sodium options of your family's favorite foods. Request restaurant nutrition information to make lower sodium choices. Problem ... burritos and tacos; and soup. Processed foods and restaurant foods. Most sodium is already in food before ...

  2. Urban transportation: Perspectives on mobility and choice

    NASA Technical Reports Server (NTRS)

    Sincoff, M. Z. (Editor); Dajani, J. S. (Editor); Arnold, G. R.; Bird, J. W.; Brooks, C. M. (Editor); Cobb, W. E.; Cross, J. E.; Darby, L. F.; Erb, N. H.; Ficht, J. C.

    1974-01-01

    A study of urban transportation systems are presented characterized by intensive scrutiny of many ideas, philosophies, and academic perspectives. This report is intended to communicate some dimensions of the urban transportation problem to the general public.

  3. 28 CFR 541.12 - Inmate rights and responsibilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... fairly your petitions, questions, and problems to the court. 7. You have the right to legal counsel from an attorney of your choice by interviews and correspondence. 7. It is your responsibility to use the...

  4. MDTri: robust and efficient global mixed integer search of spaces of multiple ternary alloys: A DIRECT-inspired optimization algorithm for experimentally accessible computational material design

    DOE PAGES

    Graf, Peter A.; Billups, Stephen

    2017-07-24

    Computational materials design has suffered from a lack of algorithms formulated in terms of experimentally accessible variables. Here we formulate the problem of (ternary) alloy optimization at the level of choice of atoms and their composition that is normal for synthesists. Mathematically, this is a mixed integer problem where a candidate solution consists of a choice of three elements, and how much of each of them to use. This space has the natural structure of a set of equilateral triangles. We solve this problem by introducing a novel version of the DIRECT algorithm that (1) operates on equilateral triangles insteadmore » of rectangles and (2) works across multiple triangles. We demonstrate on a test case that the algorithm is both robust and efficient. Lastly, we offer an explanation of the efficacy of DIRECT -- specifically, its balance of global and local search -- by showing that 'potentially optimal rectangles' of the original algorithm are akin to the Pareto front of the 'multi-component optimization' of global and local search.« less

  5. Testing boundary conditions for the conjunction fallacy: effects of response mode, conceptual focus, and problem type.

    PubMed

    Wedell, Douglas H; Moro, Rodrigo

    2008-04-01

    Two experiments used within-subject designs to examine how conjunction errors depend on the use of (1) choice versus estimation tasks, (2) probability versus frequency language, and (3) conjunctions of two likely events versus conjunctions of likely and unlikely events. All problems included a three-option format verified to minimize misinterpretation of the base event. In both experiments, conjunction errors were reduced when likely events were conjoined. Conjunction errors were also reduced for estimations compared with choices, with this reduction greater for likely conjuncts, an interaction effect. Shifting conceptual focus from probabilities to frequencies did not affect conjunction error rates. Analyses of numerical estimates for a subset of the problems provided support for the use of three general models by participants for generating estimates. Strikingly, the order in which the two tasks were carried out did not affect the pattern of results, supporting the idea that the mode of responding strongly determines the mode of thinking about conjunctions and hence the occurrence of the conjunction fallacy. These findings were evaluated in terms of implications for rationality of human judgment and reasoning.

  6. The individual and beyond: a socio-rational choice model of service participation among homeless adults with substance abuse problems.

    PubMed

    Sosin, Michael R; Grossman, Susan F

    2003-01-01

    While substance user service programs can help homeless adults solve their substance use and housing problems, relatively few needy individuals use and complete these programs. The lack of participation is poorly explained by typical empirical studies, most of which consider the role in service participation of various personal traits and client problems. The current article instead seeks to explain service participation through the application of an alternative, "socio-rational choice" model. This model has three premises: Clients weigh the costs and benefits of participating in services against alternative uses of their time and resources. The clients' weighing procedures reflect their personal situations and perceptions of the treatment environment. The perceptions of their personal situations and perceptions of the treatment environment are affected by the manner in which clients react to representatives of service systems, members of their social network including both housed and homeless persons, and other individuals. Secondary evidence supports many of the model's hypotheses and generally suggests that homeless clients may be heavily affected by their experiences with individuals and systems with which they come into contact.

  7. MDTri: robust and efficient global mixed integer search of spaces of multiple ternary alloys: A DIRECT-inspired optimization algorithm for experimentally accessible computational material design

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Graf, Peter A.; Billups, Stephen

    Computational materials design has suffered from a lack of algorithms formulated in terms of experimentally accessible variables. Here we formulate the problem of (ternary) alloy optimization at the level of choice of atoms and their composition that is normal for synthesists. Mathematically, this is a mixed integer problem where a candidate solution consists of a choice of three elements, and how much of each of them to use. This space has the natural structure of a set of equilateral triangles. We solve this problem by introducing a novel version of the DIRECT algorithm that (1) operates on equilateral triangles insteadmore » of rectangles and (2) works across multiple triangles. We demonstrate on a test case that the algorithm is both robust and efficient. Lastly, we offer an explanation of the efficacy of DIRECT -- specifically, its balance of global and local search -- by showing that 'potentially optimal rectangles' of the original algorithm are akin to the Pareto front of the 'multi-component optimization' of global and local search.« less

  8. State-dependent decisions cause apparent violations of rationality in animal choice.

    PubMed

    Schuck-Paim, Cynthia; Pompilio, Lorena; Kacelnik, Alex

    2004-12-01

    Normative models of choice in economics and biology usually expect preferences to be consistent across contexts, or "rational" in economic language. Following a large body of literature reporting economically irrational behaviour in humans, breaches of rationality by animals have also been recently described. If proven systematic, these findings would challenge long-standing biological approaches to behavioural theorising, and suggest that cognitive processes similar to those claimed to cause irrationality in humans can also hinder optimality approaches to modelling animal preferences. Critical differences between human and animal experiments have not, however, been sufficiently acknowledged. While humans can be instructed conceptually about the choice problem, animals need to be trained by repeated exposure to all contingencies. This exposure often leads to differences in state between treatments, hence changing choices while preserving rationality. We report experiments with European starlings demonstrating that apparent breaches of rationality can result from state-dependence. We show that adding an inferior alternative to a choice set (a "decoy") affects choices, an effect previously interpreted as indicating irrationality. However, these effects appear and disappear depending on whether state differences between choice contexts are present or not. These results open the possibility that some expressions of maladaptive behaviour are due to oversights in the migration of ideas between economics and biology, and suggest that key differences between human and nonhuman research must be recognised if ideas are to safely travel between these fields.

  9. Preferences in Data Production Planning

    NASA Technical Reports Server (NTRS)

    Golden, Keith; Brafman, Ronen; Pang, Wanlin

    2005-01-01

    This paper discusses the data production problem, which consists of transforming a set of (initial) input data into a set of (goal) output data. There are typically many choices among input data and processing algorithms, each leading to significantly different end products. To discriminate among these choices, the planner supports an input language that provides a number of constructs for specifying user preferences over data (and plan) properties. We discuss these preference constructs, how we handle them to guide search, and additional challenges in the area of preference management that this important application domain offers.

  10. Use of Tabulated Thermochemical Data for Pure Compounds

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan S.

    1999-01-01

    Thermodynamic data for inorganic compounds is found in a variety of tabulations and computer databases. An extensive listing of sources of inorganic thermodynamic data is provided. The three major tabulations are the JANAF tables. Thermodynamic Properties of Individual Substances, and the tabulation by Barin. The notation and choice of standard states is different in each of these tabulations, so combining data from the different tabulations is often a problem. By understanding the choice of standard states, it is possible to develop simple equations for conversion of the data from one form to another.

  11. A study among dental students regarding the factors influenced dental students to choose dentistry as career

    PubMed Central

    AnbuSelvan, Gobichetti Palayam Jagatheeswaran; Gokulnathan, Subramaniam; PrabuRajan, Vilvanathan; RajaRaman, Gangadharan; Kumar, Singaravelu Suresh; Thagavelu, Arthie

    2013-01-01

    Introduction: Career choice is a complex decision for students since it determines the kind of profession that they intend to pursue in life. As students try to make a career choice while in secondary school, they face the problem of matching their career choices with their abilities and school performance. Aims: The purpose of this study was to examine factors influencing career choice among dental college students in private dental collages in Tamil Nadu, India. Settings and Design: The study was conducted using descriptive survey design with a population of 989 students. The data for this study was collected using a questionnaire and interview schedules. Materials and Methods: The data for this study was collected using questionnaire previously used by Swati Shah and Rajaraman and interview schedules. The analysis of the study was based on the factors: Outcome expectations, gender, personal interests, and other factors. Results and Conclusion: The most common reason for among the dental students to choose dental science as their career choice was self-interested followed by didn′t get medicine degree, prestige and gives respect. The least common reasons observed in the study population were inspired by dentists. The findings of this study indicate that availability the most influential factors affecting career choices among students. PMID:23946573

  12. 'Health should not have to be a problem': talking health and accountability in an internet forum on veganism.

    PubMed

    Sneijder, Petra; te Molder, Hedwig F M

    2004-07-01

    This article draws upon insights from discursive psychology to examine how participants in an Internet forum on veganism orient to the relationship between food choice, health and accountability. First, we explore the ways in which participants ascribe responsibility for health problems like vitamin deficiency to individual recipients. By suggesting individual practices as a cause for problems, speakers undermine the notion that problems arise through veganism as a matter of principle. Second, we show how participants construct solutions to individual health problems as involving mundane and simple actions. Both discursive procedures enable speakers to resist negative assumptions about the potentially complicated nature of veganism in relation to health protection.

  13. Kids Create Healthy Comics | NIH MedlinePlus the Magazine

    MedlinePlus

    ... book page from Choosing the Way on reducing childhood obesity All photos courtesy of Elizabeth Anne Thompson, MUSC " ... the Way is a frank discussion of the childhood obesity problem and the role that choices in diet ...

  14. Process scales in catchment science: a new synthesis

    EPA Science Inventory

    Concerns surrounding data resolution, choice of spatial and temporal scales in research design, and problems with extrapolation of processes across spatial and temporal scales differ greatly between scientific process-elucidation research and scenario exploration for watershed ma...

  15. Il problema della scelta e della continuita della lingua straniera nella scuola dell'obbligo (Problems of Choice and Continuity of a Foreign Language in Elementary and Junior High School).

    ERIC Educational Resources Information Center

    Gotti, Maurizio

    1987-01-01

    Discusses two current problems with foreign language study in Italy: (1) Students are frequently unable to study English, the most popular language, because of a lack of qualified English teachers; and (2) Students sometimes cannot continue studying in junior high school the language they began in elementary school. (CFM)

  16. What should the management of incest pregnancies be? An ethical view presented via three cases.

    PubMed

    Yuksel, B; Kilic, S; Akin Su, F; Tasdemir, N; Uzunlar, O; Mollamahmutoglu, L

    2008-01-01

    Incest is a taboo and a neglected social problem. Especially in the adolescent population, which is a very sensitive period of development, it becomes harder for the patients to share their secret with either legal or health authorities. Sometimes pregnancy becomes the only vehicle to uncover this secret. There is a contradiction whether their pregnancies should continue or not. Some authors believe abortion is the best choice for the victim to pull herself together, whereas others advocate that it is just another trauma that will not solve the problem but merely hide it. In this report, three paternal incest cases and their pregnancies will be presented. The aim is not only to discuss the different points of view regarding the management of these pregnancies but also to make the clinicians think about the different choices before making a decision.

  17. Gain-Loss Framing and Choice: Separating Outcome Formulations from Descriptor Formulations.

    PubMed

    Mandel, David R.

    2001-05-01

    This article reexamines the assumptions underlying the disease problem used by Tversky and Kahneman (1981) to illustrate gain-loss formulation effects. It is argued that their reported effect may have been due to asymmetries in the ambiguity of the sure and risky prospects and to the entanglement of two distinct types of formulation manipulations: one having to do with the expected outcomes that are made explicit (positive vs negative) and the other having to do with the descriptors used to convey the relevant expected outcomes (lives saved/not saved vs lives lost/not lost). Two experiments using a formally equivalent problem in which these confounds were eliminated revealed no significant predictive effect of either descriptor or outcomes frames on choice, although a marginally significant framing effect was obtained in Experiment 1 when the signs of the two framing manipulations were congruent. Implications for prospect theory are discussed. Copyright 2001 Academic Press.

  18. The veil of ignorance and health resource allocation.

    PubMed

    Soto, Carlos

    2012-08-01

    Some authors view the veil of ignorance as a preferred method for allocating resources because it imposes impartiality by stripping deliberators of knowledge of their personal identity. Using some prominent examples of such reasoning in the health care sector, I will argue for the following claims. First, choice behind a veil of ignorance often fails to provide clear guidance regarding resource allocation. Second, regardless of whether definite results could be derived from the veil, these results do not in themselves have important moral standing. This is partly because the veil does not determine which features are morally relevant for a given distributive problem. Third, even when we have settled the question of what features to count, choice behind a veil of ignorance arguably fails to take persons seriously. Ultimately, we do not need the veil to solve distributive problems, and we have good reason to appeal to some other distributive model.

  19. Motion and force control for multiple cooperative manipulators

    NASA Technical Reports Server (NTRS)

    Wen, John T.; Kreutz, Kenneth

    1989-01-01

    The motion and force control of multiple robot arms manipulating a commonly held object is addressed. A general control paradigm that decouples the motion and force control problems is introduced. For motion control, there are three natural choices: (1) joint torques, (2) arm-tip force vectors, and (3) the acceleration of a generalized coordinate. Choice (1) allows a class of relatively model-independent control laws by exploiting the Hamiltonian structure of the open-loop system; (2) and (3) require the full model information but produce simpler problems. To resolve the nonuniqueness of the joint torques, two methods are introduced. If the arm and object models are available, the allocation of the desired end-effector control force to the joint actuators can be optimized; otherwise the internal force can be controlled about some set point. It is shown that effective force regulation can be achieved even if little model information is available.

  20. Decision theory for computing variable and value ordering decisions for scheduling problems

    NASA Technical Reports Server (NTRS)

    Linden, Theodore A.

    1993-01-01

    Heuristics that guide search are critical when solving large planning and scheduling problems, but most variable and value ordering heuristics are sensitive to only one feature of the search state. One wants to combine evidence from all features of the search state into a subjective probability that a value choice is best, but there has been no solid semantics for merging evidence when it is conceived in these terms. Instead, variable and value ordering decisions should be viewed as problems in decision theory. This led to two key insights: (1) The fundamental concept that allows heuristic evidence to be merged is the net incremental utility that will be achieved by assigning a value to a variable. Probability distributions about net incremental utility can merge evidence from the utility function, binary constraints, resource constraints, and other problem features. The subjective probability that a value is the best choice is then derived from probability distributions about net incremental utility. (2) The methods used for rumor control in Bayesian Networks are the primary way to prevent cycling in the computation of probable net incremental utility. These insights lead to semantically justifiable ways to compute heuristic variable and value ordering decisions that merge evidence from all available features of the search state.

  1. Repetition and comprehension of spoken sentences by reading-disabled children.

    PubMed

    Shankweiler, D; Smith, S T; Mann, V A

    1984-11-01

    The language problems of reading-disabled elementary school children are not confined to written language alone. These children often exhibit problems of ordered recall of verbal materials that are equally severe whether the materials are presented in printed or in spoken form. Sentences that pose problems of pronoun reference might be expected to place a special burden on short-term memory because close grammatical relationships obtain between words that are distant from one another. With this logic in mind, third-grade children with specific reading disability and classmates matched for age and IQ were tested on five sentence types, each of which poses a problem in assigning pronoun reference. On one occasion the children were tested for comprehension of the sentences by a forced-choice picture verification task. On a later occasion they received the same sentences as a repetition test. Good and poor readers differed significantly in immediate recall of the reflexive sentences, but not in comprehension of them as assessed by picture choice. It was suggested that the pictures provided cues which lightened the memory load, a possibility that could explain why the poor readers were not demonstrably inferior in comprehension of the sentences even though they made significantly more errors than the good readers in recalling them.

  2. Techniques for Accelerating Iterative Methods for the Solution of Mathematical Problems

    DTIC Science & Technology

    1989-07-01

    m, we can find a solu ion to the problem by using generalized inverses. Hence, ;= Ih.i = GAi = G - where G is of the form (18). A simple choice for V...have understood why I was not available for many of their activities and not home many of the nights. Their love is forever. I have saved the best for...Xk) Extrapolation applied to terms xP through Xk F Operator on x G Iteration function Ik Identity matrix of rank k Solution of the problem or the limit

  3. Graded Multiple Choice Questions: Rewarding Understanding and Preventing Plagiarism

    NASA Astrophysics Data System (ADS)

    Denyer, G. S.; Hancock, D.

    2002-08-01

    This paper describes an easily implemented method that allows the generation and analysis of graded multiple-choice examinations. The technique, which uses standard functions in user-end software (Microsoft Excel 5+), can also produce several different versions of an examination that can be employed to prevent the reward of plagarism. The manuscript also discusses the advantages of having a graded marking system for the elimination of ambiguities, use in multi-step calculation questions, and questions that require extrapolation or reasoning. The advantages of the scrambling strategy, which maintains the same question order, is discussed with reference to student equity. The system provides a non-confrontational mechanism for dealing with cheating in large-class multiple-choice examinations, as well as providing a reward for problem solving over surface learning.

  4. Determinants of Marital Quality in an Arranged Marriage Society

    PubMed Central

    Allendorf, Keera

    2013-01-01

    Drawing on a uniquely large number of items on marital quality, this study explores the determinants of marital quality in Chitwan Valley, Nepal. Marital quality is measured with five dimensions identified through exploratory factor analysis, including satisfaction, communication, togetherness, problems, and disagreements. Gender, education, and spouse choice emerge as the most important determinants of these dimensions of marital quality. Specifically, men, those with more schooling, and those who participated in the choice of their spouse have higher levels of marital quality. By contrast, caste, occupation, age at marriage, marital duration, and number of children have little to no association with marital quality. While gender, education, and spouse choice emerge as key determinants of marital quality in this context, the majority of variation in marital quality remains unexplained. PMID:23146598

  5. Considerations of persistence and security in CHOICES, an object-oriented operating system

    NASA Technical Reports Server (NTRS)

    Campbell, Roy H.; Madany, Peter W.

    1990-01-01

    The current design of the CHOICES persistent object implementation is summarized, and research in progress is outlined. CHOICES is implemented as an object-oriented system, and persistent objects appear to simplify and unify many functions of the system. It is demonstrated that persistent data can be accessed through an object-oriented file system model as efficiently as by an existing optimized commercial file system. The object-oriented file system can be specialized to provide an object store for persistent objects. The problems that arise in building an efficient persistent object scheme in a 32-bit virtual address space that only uses paging are described. Despite its limitations, the solution presented allows quite large numbers of objects to be active simultaneously, and permits sharing and efficient method calls.

  6. Future self-continuity: how conceptions of the future self transform intertemporal choice

    PubMed Central

    Hershfield, Hal E.

    2013-01-01

    With life expectancy dramatically increasing throughout much of the world, people have to make choices with a longer future in mind than they ever had to before. Yet, many indicators suggest that undersaving for the long term often occurs: in America, for instance, many individuals will not be able to maintain their preretirement standard of living in retirement. Previous research has tried to understand problems with intertemporal choice by focusing on the ways in which people treat present and future rewards. In this paper, the author reviews a burgeoning body of theoretical and empirical work that takes a different viewpoint, one that focuses on how perceptions of the self over time can dramatically affect decision making. Specifically, when the future self shares similarities with the present self, when it is viewed in vivid and realistic terms, and when it is seen in a positive light, people are more willing to make choices today that may benefit them at some point in the years to come. PMID:22023566

  7. Condition-dependent mate choice: A stochastic dynamic programming approach.

    PubMed

    Frame, Alicia M; Mills, Alex F

    2014-09-01

    We study how changing female condition during the mating season and condition-dependent search costs impact female mate choice, and what strategies a female could employ in choosing mates to maximize her own fitness. We address this problem via a stochastic dynamic programming model of mate choice. In the model, a female encounters males sequentially and must choose whether to mate or continue searching. As the female searches, her own condition changes stochastically, and she incurs condition-dependent search costs. The female attempts to maximize the quality of the offspring, which is a function of the female's condition at mating and the quality of the male with whom she mates. The mating strategy that maximizes the female's net expected reward is a quality threshold. We compare the optimal policy with other well-known mate choice strategies, and we use simulations to examine how well the optimal policy fares under imperfect information. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Decisions in Motion: Decision Dynamics during Intertemporal Choice reflect Subjective Evaluation of Delayed Rewards

    NASA Astrophysics Data System (ADS)

    O'Hora, Denis; Carey, Rachel; Kervick, Aoife; Crowley, David; Dabrowski, Maciej

    2016-02-01

    People tend to discount rewards or losses that occur in the future. Such delay discounting has been linked to many behavioral and health problems, since people choose smaller short-term gains over greater long-term gains. We investigated whether the effect of delays on the subjective value of rewards is expressed in how people move when they make choices. Over 600 patrons of the RISK LAB exhibition hosted by the Science Gallery DublinTM played a short computer game in which they used a computer mouse to choose between amounts of money at various delays. Typical discounting effects were observed and decision dynamics indicated that choosing smaller short-term rewards became easier (i.e., shorter response times, tighter trajectories, less vacillation) as the delays until later rewards increased. Based on a sequence of choices, subjective values of delayed outcomes were estimated and decision dynamics during initial choices predicted these values. Decision dynamics are affected by subjective values of available options and thus provide a means to estimate such values.

  9. Errors as a Means of Reducing Impulsive Food Choice.

    PubMed

    Sellitto, Manuela; di Pellegrino, Giuseppe

    2016-06-05

    Nowadays, the increasing incidence of eating disorders due to poor self-control has given rise to increased obesity and other chronic weight problems, and ultimately, to reduced life expectancy. The capacity to refrain from automatic responses is usually high in situations in which making errors is highly likely. The protocol described here aims at reducing imprudent preference in women during hypothetical intertemporal choices about appetitive food by associating it with errors. First, participants undergo an error task where two different edible stimuli are associated with two different error likelihoods (high and low). Second, they make intertemporal choices about the two edible stimuli, separately. As a result, this method decreases the discount rate for future amounts of the edible reward that cued higher error likelihood, selectively. This effect is under the influence of the self-reported hunger level. The present protocol demonstrates that errors, well known as motivationally salient events, can induce the recruitment of cognitive control, thus being ultimately useful in reducing impatient choices for edible commodities.

  10. Errors as a Means of Reducing Impulsive Food Choice

    PubMed Central

    Sellitto, Manuela; di Pellegrino, Giuseppe

    2016-01-01

    Nowadays, the increasing incidence of eating disorders due to poor self-control has given rise to increased obesity and other chronic weight problems, and ultimately, to reduced life expectancy. The capacity to refrain from automatic responses is usually high in situations in which making errors is highly likely. The protocol described here aims at reducing imprudent preference in women during hypothetical intertemporal choices about appetitive food by associating it with errors. First, participants undergo an error task where two different edible stimuli are associated with two different error likelihoods (high and low). Second, they make intertemporal choices about the two edible stimuli, separately. As a result, this method decreases the discount rate for future amounts of the edible reward that cued higher error likelihood, selectively. This effect is under the influence of the self-reported hunger level. The present protocol demonstrates that errors, well known as motivationally salient events, can induce the recruitment of cognitive control, thus being ultimately useful in reducing impatient choices for edible commodities. PMID:27341281

  11. Factors influencing food choices of food-allergic consumers: findings from focus groups.

    PubMed

    Sommer, I; Mackenzie, H; Venter, C; Dean, T

    2012-10-01

    Up to 35% of the population modify their diet for adverse reactions to food. This study described the food choice behaviour of diagnosed food-allergic (DFA), self-reported food-allergic or intolerant (SFA) and nonfood-allergic (NFA) consumers, and explored differences between them. Six focus groups with adults (n = 44) were conducted. Data analysis was performed using thematic content analysis. Compared to NFA participants, DFA consumers were deprived of satisfaction and pleasure from foods, experienced difficulties finding safe foods and had to be organized with eating. SFA participants faced similar problems, but to a lesser degree; their food choices were strongly influenced by emotional factors or health awareness. Food-allergic consumers' food choices are influenced by a number of factors that differ to those of NFA consumers. It is therefore important to offer people with food allergies or intolerances advice that goes beyond how to avoid allergens. © 2012 John Wiley & Sons A/S.

  12. Student reflections on choosing to study science post-16

    NASA Astrophysics Data System (ADS)

    Pike, Angela G.; Dunne, Máiréad

    2011-06-01

    The research recounted in this paper was designed primarily to attempt to understand the reasons for the low uptake of the natural sciences beyond compulsory education in England. This has caused widespread concern within governmental quarters, university science departments and the scientific community as a whole. This research explored the problem from the position of the students who recently made their choices. The student voices were heard through a series of interviews which highlighted the complexities of the process of post-16 choice. Social theories of pedagogy and identity, such as those of Basil Bernstein, were used in an analysis of the interview texts. Dominant themes used by the students in rationalising their post-16 subject choice related to their past pedagogical experiences, school discourses of differentiation and the students' notions of their future educational and occupational pathways. This study provides no simple solutions but highlights the importance of student voice to our understandings of what influences subject choice at this critical post-16 stage.

  13. Compressed modes for variational problems in mathematics and physics

    PubMed Central

    Ozoliņš, Vidvuds; Lai, Rongjie; Caflisch, Russel; Osher, Stanley

    2013-01-01

    This article describes a general formalism for obtaining spatially localized (“sparse”) solutions to a class of problems in mathematical physics, which can be recast as variational optimization problems, such as the important case of Schrödinger’s equation in quantum mechanics. Sparsity is achieved by adding an regularization term to the variational principle, which is shown to yield solutions with compact support (“compressed modes”). Linear combinations of these modes approximate the eigenvalue spectrum and eigenfunctions in a systematically improvable manner, and the localization properties of compressed modes make them an attractive choice for use with efficient numerical algorithms that scale linearly with the problem size. PMID:24170861

  14. Compressed modes for variational problems in mathematics and physics.

    PubMed

    Ozolins, Vidvuds; Lai, Rongjie; Caflisch, Russel; Osher, Stanley

    2013-11-12

    This article describes a general formalism for obtaining spatially localized ("sparse") solutions to a class of problems in mathematical physics, which can be recast as variational optimization problems, such as the important case of Schrödinger's equation in quantum mechanics. Sparsity is achieved by adding an regularization term to the variational principle, which is shown to yield solutions with compact support ("compressed modes"). Linear combinations of these modes approximate the eigenvalue spectrum and eigenfunctions in a systematically improvable manner, and the localization properties of compressed modes make them an attractive choice for use with efficient numerical algorithms that scale linearly with the problem size.

  15. The Influence of Framing on Risky Decisions: A Meta-analysis.

    PubMed

    Kühberger

    1998-07-01

    In framing studies, logically equivalent choice situations are differently described and the resulting preferences are studied. A meta-analysis of framing effects is presented for risky choice problems which are framed either as gains or as losses. This evaluates the finding that highlighting the positive aspects of formally identical problems does lead to risk aversion and that highlighting their equivalent negative aspects does lead to risk seeking. Based on a data pool of 136 empirical papers that reported framing experiments with nearly 30,000 participants, we calculated 230 effect sizes. Results show that the overall framing effect between conditions is of small to moderate size and that profound differences exist between research designs. Potentially relevant characteristics were coded for each study. The most important characteristics were whether framing is manipulated by changing reference points or by manipulating outcome salience, and response mode (choice vs. rating/judgment). Further important characteristics were whether options differ qualitatively or quantitatively in risk, whether there is one or multiple risky events, whether framing is manipulated by gain/loss or by task-responsive wording, whether dependent variables are measured between- or within- subjects, and problem domains. Sample (students vs. target populations) and unit of analysis (individual vs. group) was not influential. It is concluded that framing is a reliable phenomenon, but that outcome salience manipulations, which constitute a considerable amount of work, have to be distinguished from reference point manipulations and that procedural features of experimental settings have a considerable effect on effect sizes in framing experiments. Copyright 1998 Academic Press.

  16. Rational choice of peritoneal dialysis catheter.

    PubMed

    Dell'Aquila, Roberto; Chiaramonte, Stefano; Rodighiero, Maria Pia; Spanó, Emilia; Di Loreto, Pierluigi; Kohn, Catalina Ocampo; Cruz, Dinna; Polanco, Natalia; Kuang, Dingwei; Corradi, Valentina; De Cal, Massimo; Ronco, Claudio

    2007-06-01

    The peritoneal catheter should be a permanent and safe access to the peritoneal cavity. Catheter-related problems are often the cause of permanent transfer to hemodialysis (HD) in up to 20% of peritoneal dialysis (PD) patients; in some cases, these problems require a temporary period on HD. Advances in connectology have reduced the incidence of peritonitis, and so catheter-related complications during PD have become a major concern. In the last few years, novel techniques have emerged in the field of PD: new dialysis solutions, better connectology, and cyclers for automated PD. However, extracorporeal dialysis has continued to improve in terms of methods and patient survival, but PD has failed to do so. The main reason is that peritoneal access has remained problematical. The peritoneal catheter is the major obstacle to wide-spread use of PD. Overcoming catheter-related problems means giving a real chance to development of the peritoneal technique. Catheters should be as efficient, safe, and acceptable as possible. Since its introduction in the mid-1960s, the Tenckhoff catheter has not become obsolete: dozens of new models have been proposed, but none has significantly reduced the pre-dominance of the first catheter. No convincing prospective data demonstrate the superiority of any peritoneal catheter, and so it seems that factors other than choice of catheter are what affect survival and complication rates. Efforts to improve peritoneal catheter survival and complication rates should probably focus on factors other than the choice of catheter. The present article provides an overview of the characteristics of the best-known peritoneal catheters.

  17. Nonlinear Socio-Ecological Dynamics and First Principles ofCollective Choice Behavior of ``Homo Socialis"

    NASA Astrophysics Data System (ADS)

    Sonis, M.

    Socio-ecological dynamics emerged from the field of Mathematical SocialSciences and opened up avenues for re-examination of classical problems of collective behavior in Social and Spatial sciences. The ``engine" of this collective behavior is the subjective mental evaluation of level of utilities in the future, presenting sets of composite socio-economic-temporal-locational advantages. These dynamics present new laws of collective multi-population behavior which are the meso-level counterparts of the utility optimization individual behavior. The central core of the socio-ecological choice dynamics includes the following first principle of the collective choice behavior of ``Homo Socialis" based on the existence of ``collective consciousness": the choice behavior of ``Homo Socialis" is a collective meso-level choice behavior such that the relative changes in choice frequencies depend on the distribution of innovation alternatives between adopters of innovations. The mathematical basis of the Socio-Ecological Dynamics includes two complementary analytical approaches both based on the use of computer modeling as a theoretical and simulation tool. First approach is the ``continuous approach" --- the systems of ordinary and partial differential equations reflecting the continuous time Volterra ecological formalism in a form of antagonistic and/or cooperative collective hyper-games between different sub-sets of choice alternatives. Second approach is the ``discrete approach" --- systems of difference equations presenting a new branch of the non-linear discrete dynamics --- the Discrete Relative m-population/n-innovations Socio-Spatial Dynamics (Dendrinos and Sonis, 1990). The generalization of the Volterra formalism leads further to the meso-level variational principle of collective choice behavior determining the balance between the resulting cumulative social spatio-temporal interactions among the population of adopters susceptible to the choice alternatives and the cumulative equalization of the power of elites supporting different choice alternatives. This balance governs the dynamic innovation choice process and constitutes the dynamic meso-level counterpart of the micro-economic individual utility maximization principle.

  18. Asronomical refraction: Computational methods for all zenith angles

    NASA Technical Reports Server (NTRS)

    Auer, L. H.; Standish, E. M.

    2000-01-01

    It is shown that the problem of computing astronomical refraction for any value of the zenith angle may be reduced to a simple, nonsingular, numerical quadrature when the proper choice is made for the independent variable of integration.

  19. Commuter choice managers and parking managers coordination

    DOT National Transportation Integrated Search

    2002-11-01

    Shared use park and ride represents a unique approach for addressing parking problems, and can offer substantial savings in land and development costs. One of the fundamental factors that determines the success of this approach is the level of coordi...

  20. Wind-induced vibration of stay cables

    DOT National Transportation Integrated Search

    2007-08-01

    Cable-stayed bridges have become the form of choice over the past several decades for bridges in the medium- to long-span range. In some cases, serviceability problems involving large amplitude vibrations of stay cables under certain wind and rain co...

  1. Problems and Issues Related to Alternative Education.

    ERIC Educational Resources Information Center

    Pilat, Mary

    1997-01-01

    Symposium participants identified policy issues in these areas related to alternative education for at-risk youth: choice, equity, public perception, definition, philosophy, stakeholder involvement, evaluation, staffing, curriculum, governance, and financing. Public discourse and policy discussion were considered essential to implementing…

  2. Optimal Thermal Design of a Multishield Thermal Protection System of Reusable Space Vehicles

    NASA Astrophysics Data System (ADS)

    Maiorova, I. A.; Prosuntsov, P. V.; Zuev, A. V.

    2016-03-01

    We have solved the problem of the optimal thermal design of a multishield thermal protection system of reusable space vehicles due to the choice of the optimal position and materials of radiation shields.

  3. Computer grading of examinations

    NASA Technical Reports Server (NTRS)

    Frigerio, N. A.

    1969-01-01

    A method, using IBM cards and computer processing, automates examination grading and recording and permits use of computational problems. The student generates his own answers, and the instructor has much greater freedom in writing questions than is possible with multiple choice examinations.

  4. Behavioral Economic Indicators of Drinking Problem Severity and Initial Outcomes Among Problem Drinkers Attempting Natural Recovery: A Cross-sectional Naturalistic Study

    PubMed Central

    Tucker, Jalie A.; Cheong, JeeWon; Chandler, Susan D.; Lambert, Brice H.; Kwok, Heather; Pietrzak, Brittney

    2016-01-01

    Background and aims Research using different behavioral economic (BE) and time perspective (TP) measures suggests that substance misusers show greater sensitivity to shorter term contingencies than normal controls, but multiple measures have seldom been investigated together. This study evaluated the extent to which multiple BE and TP measures were associated with drinking problem severity, distinguished initial outcomes of natural recovery attempts, and shared common variance. Hypotheses were (1) greater problem severity would be associated with greater impulsivity and demand for alcohol and shorter TPs; and (2) low-risk drinking would be associated with greater sensitivity to longer term contingencies compared with abstinence. Design Cross-sectional naturalistic field study. Setting Southern United States. Participants Problem drinkers, recently resolved without treatment (N = 191 [76.4% male], M age = 50.1 years) recruited using media advertisements. Measurements Drinking practices, dependence levels, and alcohol-related problems prior to stopping problem drinking were assessed during structured field interviews. Measures included the Zimbardo Time Perspective Inventory; BE analogue choice tasks (Delay Discounting [DD], Melioration-Maximization [MM], Alcohol Purchase Task [APT]); and the Alcohol-Savings Discretionary Expenditure (ASDE) index, derived from real spending on alcohol and voluntary savings during the year before problem cessation. Findings Measures of demand based on real (ASDE) and hypothetical (APT) spending on alcohol were associated with problem severity (ps < .05), but DD, MM, and TP measures were not. More balanced pre-resolution spending on alcohol versus saving for the future distinguished low-risk drinking from abstinent resolutions (ASDE OR = 5.59; p < .001). BE measures did not share common variance. Conclusions Two behavioural assessment tools that measure spending on alcohol, the Alcohol Purchase Task and the Alcohol-Savings Discretionary Expenditure index, appear to be reliable in assessing the severity of drinking problems. The ASDE index also may aid choices between low-risk and abstinent drinking goals. PMID:27318078

  5. Improved discriminability of spatiotemporal neural patterns in rat motor cortical areas as directional choice learning progresses

    PubMed Central

    Mao, Hongwei; Yuan, Yuan; Si, Jennie

    2015-01-01

    Animals learn to choose a proper action among alternatives to improve their odds of success in food foraging and other activities critical for survival. Through trial-and-error, they learn correct associations between their choices and external stimuli. While a neural network that underlies such learning process has been identified at a high level, it is still unclear how individual neurons and a neural ensemble adapt as learning progresses. In this study, we monitored the activity of single units in the rat medial and lateral agranular (AGm and AGl, respectively) areas as rats learned to make a left or right side lever press in response to a left or right side light cue. We noticed that rat movement parameters during the performance of the directional choice task quickly became stereotyped during the first 2–3 days or sessions. But learning the directional choice problem took weeks to occur. Accompanying rats' behavioral performance adaptation, we observed neural modulation by directional choice in recorded single units. Our analysis shows that ensemble mean firing rates in the cue-on period did not change significantly as learning progressed, and the ensemble mean rate difference between left and right side choices did not show a clear trend of change either. However, the spatiotemporal firing patterns of the neural ensemble exhibited improved discriminability between the two directional choices through learning. These results suggest a spatiotemporal neural coding scheme in a motor cortical neural ensemble that may be responsible for and contributing to learning the directional choice task. PMID:25798093

  6. Equitable access to elective hospital services: the introduction of patient choice in a decentralised healthcare system.

    PubMed

    Ringard, Ånen

    2012-02-01

    During the 1980s and 1990s, increased waiting times for elective surgery was perceived to be a major accessibility problem in many countries. In an attempt to improve access, hospital choice reforms were introduced in a number of countries. In Norway, a nationwide reform to improve access came into effect in 2001. At the same time, renewed support was expressed for the long-standing political aim of ensuring equal access to healthcare services for all citizens regardless of their social position. The current aim is to analyse the relationship of the hospital choice reform and the goal of equitable access to hospital services. A survey conducted among Norwegian patients in 2004 provided information about whether a choice of hospital had been made. Information from the survey was merged with administrative data from the hospital that performed the treatment. The survey provided data on patients' socioeconomic position. Demographics, medical need, and prior use of healthcare services were controlled for to determine the effect of socioeconomic position on hospital choice. The patient's socioeconomic position, measured by education, was found to be significantly associated with hospital choice. The relationship resembled that of a social gradient. Patients with a primary education were less likely to have made a choice, followed by those with secondary education or a lower university degree. Patients with higher university education were most likely to have chosen. Hospital selection is a demanding task for many patients. Policymakers should therefore focus on crafting and implementing tools necessary for supporting uptake of choice in disadvantaged groups.

  7. Credit Assignment in a Motor Decision Making Task Is Influenced by Agency and Not Sensory Prediction Errors.

    PubMed

    Parvin, Darius E; McDougle, Samuel D; Taylor, Jordan A; Ivry, Richard B

    2018-05-09

    Failures to obtain reward can occur from errors in action selection or action execution. Recently, we observed marked differences in choice behavior when the failure to obtain a reward was attributed to errors in action execution compared with errors in action selection (McDougle et al., 2016). Specifically, participants appeared to solve this credit assignment problem by discounting outcomes in which the absence of reward was attributed to errors in action execution. Building on recent evidence indicating relatively direct communication between the cerebellum and basal ganglia, we hypothesized that cerebellar-dependent sensory prediction errors (SPEs), a signal indicating execution failure, could attenuate value updating within a basal ganglia-dependent reinforcement learning system. Here we compared the SPE hypothesis to an alternative, "top-down" hypothesis in which changes in choice behavior reflect participants' sense of agency. In two experiments with male and female human participants, we manipulated the strength of SPEs, along with the participants' sense of agency in the second experiment. The results showed that, whereas the strength of SPE had no effect on choice behavior, participants were much more likely to discount the absence of rewards under conditions in which they believed the reward outcome depended on their ability to produce accurate movements. These results provide strong evidence that SPEs do not directly influence reinforcement learning. Instead, a participant's sense of agency appears to play a significant role in modulating choice behavior when unexpected outcomes can arise from errors in action execution. SIGNIFICANCE STATEMENT When learning from the outcome of actions, the brain faces a credit assignment problem: Failures of reward can be attributed to poor choice selection or poor action execution. Here, we test a specific hypothesis that execution errors are implicitly signaled by cerebellar-based sensory prediction errors. We evaluate this hypothesis and compare it with a more "top-down" hypothesis in which the modulation of choice behavior from execution errors reflects participants' sense of agency. We find that sensory prediction errors have no significant effect on reinforcement learning. Instead, instructions influencing participants' belief of causal outcomes appear to be the main factor influencing their choice behavior. Copyright © 2018 the authors 0270-6474/18/384521-10$15.00/0.

  8. [School choice and vocational guidance for schoolchildren with chronic diseases and other health problems].

    PubMed

    Lancić, Franciska; Majski-Cesarec, Slavenka; Musil, Vera

    2010-09-01

    By following a child's growth, development, and health, school medicine specialist can see opportunities for career choice. Special attention is needed for schoolchildren with chronic diseases and developmental difficulties, because of limited occupation choices. Studies report 10 % to 15 % prevalence of chronic diseases among schoolchildren. Parents and children should be informed about child's limitations before career choice. It would be helpful for the students to develop interests for occupations that are not contraindicated for their condition. Physical examination gives an insight into the psycho-physical abilities of an eighth-grade primary school student for further education. During examination, counselling and vocational guidance is provided for all students with chronic diseases and other health problems. All procedures are oriented to personal abilities and preferences. The aim of this study was to analyse the reasons for vocational guidance in the Varazdin County of Croatia. It included eighth-grade students from ten primary schools from 1998/99 to 2007/08. Of 4939 students, 458 (9.3 %) with chronic diseases and health difficulties were referred to vocational guidance. Of these, 41.3 % were referred due to mental and behavioural disorders. These students were assessed and received a recommendation for at least two occupations. Forty-eight students (10.5 %) did not follow the recommendation.In a coordinated effort, school physicians, vocational guidance experts, and school and local authorities should secure enrollment of students with chronic diseases and health difficulties in secondary schools and follow their development and education to provide them the best available career opportunities.

  9. Learning the opportunity cost of time in a patch-foraging task

    PubMed Central

    Constantino, Sara; Daw, Nathaniel D.

    2015-01-01

    Although most decision research concerns choice between simultaneously presented options, in many situations options are encountered serially and the decision is whether to exploit an option or search for a better one. Such problems have a rich history in animal foraging but we know little about the psychological processes involved. In particular, it is unknown whether learning in these problems is supported by the well studied neurocomputational mechanisms involved in more conventional tasks. We investigated how humans learn in a foraging task, which requires deciding whether to harvest a depleting resource or switch to a replenished one. The optimal choice (given by the Marginal Value Theorem; MVT) requires comparing the immediate return from harvesting to the opportunity cost of time, which is given by the long-run average reward. In two experiments, we varied opportunity cost across blocks. Subjects adjusted their behavior to blockwise changes in environmental characteristics. We examined how subjects learned their choice strategies by comparing choice adjustments to a learning rule suggested by the MVT (where the opportunity cost threshold is estimated as an average over previous rewards) and to the predominant incremental learning theory in neuroscience, temporal-difference learning (TD). Trial-by-trial decisions were better explained by the MVT threshold learning rule. These findings expand on the foraging literature, which has focused on steady-state behavior, by elucidating a computational mechanism for learning in switching tasks that is distinct from those used in traditional tasks, and suggest connections to research on average reward rates in other domains of neuroscience. PMID:25917000

  10. Consumers of eldercare in Sweden: the semblance of choice.

    PubMed

    Meinow, Bettina; Parker, Marti G; Thorslund, Mats

    2011-11-01

    In Sweden and other countries, the benefits of user choice and market forces are often voiced in relation to the provision of medical care and social services. Policy makers increasingly view people as customers and consumers of care services. Among very old people-the most frequent care users-how many have the capacity necessary to find information and make decisions concerning providers of medical and social services? Using a nationally representative sample of Swedes aged 77+ (SWEOLD) in 2002 this study describes the prevalence of cognitive, physical and sensory resources associated with the capacity to make and carry out informed choices concerning medical and social care providers. Results showed that one third of a nationally representative sample of persons aged 77+ scored low on a cognitive test or they were so cognitively impaired that they could not be interviewed directly. Another 22% scored poorly on a test of the ability to find and process information. A further 32% had adequate cognition but had limitations in sensory function or mental vitality or were unable to go outside on their own. A total of 10% did not report any of the measured problems. In general, care utilisation increases with age. As health problems increase, physical and cognitive abilities decline. Results suggest that those elderly people who are most dependent on care services and who could benefit most from a "good choice", are also those who have the highest prevalence of cognitive and physical limitations associated with the capacity to act as a rational consumer of care services. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Decision dynamics of departure times: Experiments and modeling

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoyan; Han, Xiao; Bao, Jian-Zhang; Jiang, Rui; Jia, Bin; Yan, Xiaoyong; Zhang, Boyu; Wang, Wen-Xu; Gao, Zi-You

    2017-10-01

    A fundamental problem in traffic science is to understand user-choice behaviors that account for the emergence of complex traffic phenomena. Despite much effort devoted to theoretically exploring departure time choice behaviors, relatively large-scale and systematic experimental tests of theoretical predictions are still lacking. In this paper, we aim to offer a more comprehensive understanding of departure time choice behaviors in terms of a series of laboratory experiments under different traffic conditions and feedback information provided to commuters. In the experiment, the number of recruited players is much larger than the number of choices to better mimic the real scenario, in which a large number of commuters will depart simultaneously in a relatively small time window. Sufficient numbers of rounds are conducted to ensure the convergence of collective behavior. Experimental results demonstrate that collective behavior is close to the user equilibrium, regardless of different scales and traffic conditions. Moreover, the amount of feedback information has a negligible influence on collective behavior but has a relatively stronger effect on individual choice behaviors. Reinforcement learning and Fermi learning models are built to reproduce the experimental results and uncover the underlying mechanism. Simulation results are in good agreement with the experimentally observed collective behaviors.

  12. Israelis' perceived motivation for choosing a nursing career.

    PubMed

    Ben Natan, Merav; Becker, Fainna

    2010-05-01

    Recruitment problems are one of the main reasons for the shortage of nurses in Israel and elsewhere. The purpose of this study is to clarify factors affecting choice of ideal careers and nursing careers among the general population. A questionnaire constructed by McCabe et al. (2005) was administered to 309 men and women aged 18-50. Data were analyzed by quantitative methods. Research findings indicate that 8% of respondents expressed interest in studying nursing. Significant differences were reported between the choice of ideal and nursing careers. Nursing careers were perceived as lacking interest, challenge, creativity, responsibility, varied wages, high status, comfortable conditions, versus ideal careers. A moderately positive correlation was identified between choice of a nursing career and intrinsic factors affecting this choice. People motivated by desire to help others rather than personal interest or challenges are predisposed to choose a nursing career. Finally, a negative correlation was identified between psychometric scores and choice of a nursing career. The study also identified a positive correlation between both the image of nursing as a profession and the availability of nursing jobs - and the decision to choose a nursing career. This study may facilitate the development of nurse recruitment programs. Copyright 2009 Elsevier Ltd. All rights reserved.

  13. Eye-tracking of visual attention in web-based assessment using the Force Concept Inventory

    NASA Astrophysics Data System (ADS)

    Han, Jing; Chen, Li; Fu, Zhao; Fritchman, Joseph; Bao, Lei

    2017-07-01

    This study used eye-tracking technology to investigate students’ visual attention while taking the Force Concept Inventory (FCI) in a web-based interface. Eighty nine university students were randomly selected into a pre-test group and a post-test group. Students took the 30-question FCI on a computer equipped with an eye-tracker. There were seven weeks of instruction between the pre- and post-test data collection. Students’ performance on the FCI improved significantly from pre-test to post-test. Meanwhile, the eye-tracking results reveal that the time students spent on taking the FCI test was not affected by student performance and did not change from pre-test to post-test. Analysis of students’ attention to answer choices shows that on the pre-test students primarily focused on the naïve choices and ignored the expert choices. On the post-test, although students had shifted their primary attention to the expert choices, they still kept a high level of attention to the naïve choices, indicating significant conceptual mixing and competition during problem solving. Outcomes of this study provide new insights on students’ conceptual development in learning physics.

  14. Risky choice with heuristics: reply to Birnbaum (2008), Johnson, Schulte-Mecklenbeck, and Willemsen (2008), and Rieger and Wang (2008).

    PubMed

    Brandstätter, Eduard; Gigerenzer, Gerd; Hertwig, Ralph

    2008-01-01

    E. Brandstätter, G. Gigerenzer, and R. Hertwig (2006) showed that the priority heuristic matches or outperforms modifications of expected utility theory in predicting choice in 4 diverse problem sets. M. H. Birnbaum (2008) argued that sets exist in which the opposite is true. The authors agree--but stress that all choice strategies have regions of good and bad performance. The accuracy of various strategies systematically depends on choice difficulty, which the authors consider a triggering variable underlying strategy selection. Agreeing with E. J. Johnson, M. Schulte-Mecklenbeck, and M. C. Willemsen (2008) that process (not "as-if") models need to be formulated, the authors show how quantitative predictions can be derived and test them. Finally, they demonstrate that many of Birnbaum's and M. O. Rieger and M. Wang's (2008) case studies championing their preferred models involved biased tests in which the priority heuristic predicted data, whereas the parameterized models were fitted to the same data. The authors propose an adaptive toolbox approach of risky choice, according to which people first seek a no-conflict solution before resorting to conflict-resolving strategies such as the priority heuristic. (c) 2008 APA, all rights reserved

  15. Categorizing health-related cues to action: using Yelp reviews of restaurants in Hawaii

    NASA Astrophysics Data System (ADS)

    Ariyasriwatana, W.; Buente, W.; Oshiro, M.; Streveler, D.

    2014-10-01

    Yelp, a social media site, undeniably has an influence on consumers' food choice in spite of its ability to reflect consumers' real voice being criticized. Since unhealthy food choices contribute to health problems, such as obesity and malnourishment, we attempted to examine these problems by better understanding consumers through health-related cues to action-a construct from the Health Belief Model (HBM)- on Yelp Honolulu's restaurant reviews. Our research revealed 13 main categories: Ingredient, Type of food, Taste, Lifestyle, Cooking, Option, Price, Portion, Well-being, Nutrition, Hygiene, Emotional attachment and indulgence, and Feeling. We argue that these categories may ultimately lead consumers to make healthier food choices. In search of the most appealing way to communicate with the target group, underlying concepts that derived from these categories can be tested. Marketers in food industry (or public health policy-makers) can craft their strategies for healthy food brands/products (or healthy eating scheme) based on the concept test research. Moreover, Yelp can apply these insights in the development of their algorithm and filter system in order to help consumers find healthy food if they wish to do so. Restaurants can also improve their strategy, menu, and communication execution to meet the growing demands of health conscious consumers.

  16. Mechanical problem-solving strategies in Alzheimer's disease and semantic dementia.

    PubMed

    Lesourd, Mathieu; Baumard, Josselin; Jarry, Christophe; Etcharry-Bouyx, Frédérique; Belliard, Serge; Moreaud, Olivier; Croisile, Bernard; Chauviré, Valérie; Granjon, Marine; Le Gall, Didier; Osiurak, François

    2016-07-01

    The goal of this study was to explore whether the tool-use disorders observed in Alzheimer's disease (AD) and semantic dementia (SD) are of the same nature as those observed in left brain-damaged (LBD) patients. Recent evidence indicates that LBD patients with apraxia of tool use encounter difficulties in solving mechanical problems, characterized by the absence of specific strategies. This pattern may show the presence of impaired mechanical knowledge, critical for both familiar and novel tool use. So, we explored the strategies followed by AD and SD patients in mechanical problem-solving tasks in order to determine whether mechanical knowledge is also impaired in these patients. We used a mechanical problem-solving task in both choice (i.e., several tools were proposed) and no-choice (i.e., only 1 tool was proposed) conditions. We analyzed quantitative data and strategy profiles. AD patients but not SD patients met difficulties in solving mechanical problem-solving tasks. However, the key finding is that AD patients, despite their difficulties, showed strategy profiles that are similar to that of SD patients or controls. Moreover, AD patients exhibited a strategy profile distinct from the one previously observed in LBD patients. Those observations lead us to consider that difficulties met by AD patients to solve mechanical problems or even to use familiar tools may not be caused by mechanical knowledge impairment per se. In broad terms, what we call apraxia of tool use in AD is certainly not the same as apraxia of tool use observed in LBD patients. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  17. Solving a novel confinement problem by spartaeine salticids that are predisposed to solve problems in the context of predation.

    PubMed

    Cross, Fiona R; Jackson, Robert R

    2015-03-01

    Intricate predatory strategies are widespread in the salticid subfamily Spartaeinae. The hypothesis we consider here is that the spartaeine species that are proficient at solving prey-capture problems are also proficient at solving novel problems. We used nine species from this subfamily in our experiments. Eight of these species (two Brettus, one Cocalus, three Cyrba, two Portia) are known for specialized invasion of other spiders' webs and for actively choosing other spiders as preferred prey ('araneophagy'). Except for Cocalus, these species also use trial and error to derive web-based signals with which they gain dynamic fine control of the resident spider's behaviour ('aggressive mimicry').The ninth species, Paracyrba wanlessi, is not araneophagic and instead specializes at preying on mosquitoes. We presented these nine species with a novel confinement problem that could be solved by trial and error. The test spider began each trial on an island in a tray of water, with an atoll surrounding the island. From the island, the spider could choose between two potential escape tactics (leap or swim), but we decided at random before the trial which tactic would fail and which tactic would achieve partial success. Our findings show that the seven aggressive-mimic species are proficient at solving the confinement problem by repeating 'correct' choices and by switching to the alternative tactic after making an 'incorrect' choice. However, as predicted, there was no evidence of C. gibbosus or P. wanlessi, the two non-aggressive-mimic species, solving the confinement problem. We discuss these findings in the context of an often-made distinction between domain-specific and domain-general cognition.

  18. Lipschitz stability for an inverse hyperbolic problem of determining two coefficients by a finite number of observations

    NASA Astrophysics Data System (ADS)

    Beilina, L.; Cristofol, M.; Li, S.; Yamamoto, M.

    2018-01-01

    We consider an inverse problem of reconstructing two spatially varying coefficients in an acoustic equation of hyperbolic type using interior data of solutions with suitable choices of initial condition. Using a Carleman estimate, we prove Lipschitz stability estimates which ensure unique reconstruction of both coefficients. Our theoretical results are justified by numerical studies on the reconstruction of two unknown coefficients using noisy backscattered data.

  19. Rotation Rate Sensing via Magnetostatic Surface Wave Propagation on a Thick Yig Ring.

    DTIC Science & Technology

    1979-12-03

    Introduction . . . . . . . . . . . 1 Background . . . . . . . . I Statement of the Problem. o o . 4 Plan of Attack. o. . o o o • 4 Sequence of...crystal growth process. It was subsequently suggested that the thin film disfiguration problem could be avoided by ma- chining the desired ring...sensor provide any practical advantages that would make it a better choice over current rate sensing schemes? Plan of Attack This thesis concerns itself

  20. State-Dependent Decisions Cause Apparent Violations of Rationality in Animal Choice

    PubMed Central

    Schuck-Paim, Cynthia; Pompilio, Lorena

    2004-01-01

    Normative models of choice in economics and biology usually expect preferences to be consistent across contexts, or “rational” in economic language. Following a large body of literature reporting economically irrational behaviour in humans, breaches of rationality by animals have also been recently described. If proven systematic, these findings would challenge long-standing biological approaches to behavioural theorising, and suggest that cognitive processes similar to those claimed to cause irrationality in humans can also hinder optimality approaches to modelling animal preferences. Critical differences between human and animal experiments have not, however, been sufficiently acknowledged. While humans can be instructed conceptually about the choice problem, animals need to be trained by repeated exposure to all contingencies. This exposure often leads to differences in state between treatments, hence changing choices while preserving rationality. We report experiments with European starlings demonstrating that apparent breaches of rationality can result from state-dependence. We show that adding an inferior alternative to a choice set (a “decoy”) affects choices, an effect previously interpreted as indicating irrationality. However, these effects appear and disappear depending on whether state differences between choice contexts are present or not. These results open the possibility that some expressions of maladaptive behaviour are due to oversights in the migration of ideas between economics and biology, and suggest that key differences between human and nonhuman research must be recognised if ideas are to safely travel between these fields. PMID:15550984

  1. Food selectivity, mealtime behavior problems, spousal stress, and family food choices in children with and without autism spectrum disorder.

    PubMed

    Curtin, C; Hubbard, K; Anderson, S E; Mick, E; Must, A; Bandini, L G

    2015-10-01

    Mealtime behavior problems and family stress occur frequently among families of children with autism spectrum disorder (ASD). However, it is unknown whether food selectivity is an associated factor. The associations of high food selectivity with mealtime behavior problems, spousal stress, and influence on family members were assessed among 53 children with ASD and 58 typically developing (TD) children ages 3-11 years. Compared to TD children, children with ASD were more likely to have high food selectivity, and their parents reported more mealtime behavior problems, higher spousal stress, and influence on what other family members ate. High food selectivity was associated with mealtime behavior problems in both groups. Interventions to reduce food selectivity may lead to decreases in mealtime behavior problems.

  2. Food Selectivity, Mealtime Behavior Problems, Spousal Stress, and Family Food Choices in Children with and without Autism Spectrum Disorder

    PubMed Central

    Curtin, C.; Hubbard, K.; Anderson, S.E.; Mick, E.; Must, A.; Bandini, L.G.

    2015-01-01

    Mealtime behavior problems and family stress occur frequently among families of children with autism spectrum disorder (ASD). However, it is unknown whether food selectivity is an associated factor. The associations of high food selectivity with mealtime behavior problems, spousal stress, and influence on family members were assessed among 53 children with ASD and 58 typically developing (TD) children ages 3–11 years. Compared to TD children, children with ASD were more likely to have high food selectivity, and their parents reported more mealtime behavior problems, higher spousal stress, and influence on what other family members ate. High food selectivity was associated with mealtime behavior problems in both groups. Interventions to reduce food selectivity may lead to decreases in mealtime behavior problems. PMID:26070276

  3. Perceptions of Chronicity and Recovery among Youth in Treatment for Substance Use Problems

    PubMed Central

    Gonzales, Rachel; Anglin, M. Douglas; Beattie, Rebecca; Ong, Chris Angelo; Glik, Deborah C.

    2012-01-01

    Purpose To explore how youth contextualize substance use problems and recovery, in general and for themselves, in relation to the commonly accepted chronicity framework. Methods Fourteen focus groups were conducted with 118 youth in substance abuse treatment settings (aged 12-24; 78.3% male; 66.1% Latino) located throughout diverse areas of Los Angeles County. Transcribed qualitative focus group data were analyzed for major substance use and recovery themes. Results Most (80%) youth do not accept a chronicity framework that conceptualizes substance use problems as recurring and constituting a life-long illness. Most (65%) view substance use problems as a function of poor behavioral choices or a developmental/social lifestyle phase. Youth perceptions of recovery tend to parallel this view, as most define recovery to mean having an improved or changed lifestyle that is achieved through making better behavioral choices (67%) and exerting personal control over one's behavior (57%) through willpower, confidence, or discipline. Other recovery themes identified by youth were substance use related (47%), wellness or well-being related (43%) and therapeutic or treatment related (14%). Conclusions Findings highlight the importance of considering youth perceptions about substance use chronicity and recovery in making improvements and promoting new developments in clinical and recovery support approaches to better meet the needs of youth with substance use problems. Findings are discussed under a theoretical context of behavior change to provide insights for the treatment and recovery communities. PMID:22824444

  4. External approach to rhinoplasty.

    PubMed

    Goodman, Wilfred S; Charbonneau, Paul A

    2015-07-01

    The technique of external rhinoplasty is outlined. Having reviewed 74 cases, its advantages and disadvantages are discussed. Reluctance to use this external approach seems to be based on emotional rather than radical grounds, for its seems to be the procedure of choice for many problems.

  5. On the tradeoffs of programming language choice for numerical modelling in geoscience. A case study comparing modern Fortran, C++/Blitz++ and Python/NumPy.

    NASA Astrophysics Data System (ADS)

    Jarecka, D.; Arabas, S.; Fijalkowski, M.; Gaynor, A.

    2012-04-01

    The language of choice for numerical modelling in geoscience has long been Fortran. A choice of a particular language and coding paradigm comes with different set of tradeoffs such as that between performance, ease of use (and ease of abuse), code clarity, maintainability and reusability, availability of open source compilers, debugging tools, adequate external libraries and parallelisation mechanisms. The availability of trained personnel and the scale and activeness of the developer community is of importance as well. We present a short comparison study aimed at identification and quantification of these tradeoffs for a particular example of an object oriented implementation of a parallel 2D-advection-equation solver in Python/NumPy, C++/Blitz++ and modern Fortran. The main angles of comparison will be complexity of implementation, performance of various compilers or interpreters and characterisation of the "added value" gained by a particular choice of the language. The choice of the numerical problem is dictated by the aim to make the comparison useful and meaningful to geoscientists. Python is chosen as a language that traditionally is associated with ease of use, elegant syntax but limited performance. C++ is chosen for its traditional association with high performance but even higher complexity and syntax obscurity. Fortran is included in the comparison for its widespread use in geoscience often attributed to its performance. We confront the validity of these traditional views. We point out how the usability of a particular language in geoscience depends on the characteristics of the language itself and the availability of pre-existing software libraries (e.g. NumPy, SciPy, PyNGL, PyNIO, MPI4Py for Python and Blitz++, Boost.Units, Boost.MPI for C++). Having in mind the limited complexity of the considered numerical problem, we present a tentative comparison of performance of the three implementations with different open source compilers including CPython and PyPy, Clang++ and GNU g++, and GNU gfortran.

  6. Conservation of energy resources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mauss, E.A.; Ullmann, J.E.

    1979-01-01

    The following papers are included: Social, Political, and Ethical Choices in Developing Energy Policies by John C. Sawhill; Choices in Developing Energy Choices by Amory B. Lovins; Energy Conservation: Some Technical and Economic Possibilities by Lloyd J. Thomas; Four Anxieties about a Vigorous National Conservation Program by R. H. Socolow; Energy Conservation: The Weight of the Past and the Problems of Persuasion by John E. Ullman; The Energy Value of Our Existing Stock of Buildings by Richard G. Stein; The Role of Energy Conservation in Industry by Eric R. Zausner; The Role of Energy Conservation in Industry: Discussion Paper bymore » Charles A. Berg; End-Use Technology: The Next Twenty-Five Years by George R. Murray and Michael Power; The Department of Energy's End-Use Conservation Program by Marc Ross; and The Politics of Energy Conservation by Daniel Yergin. (MHR)« less

  7. Maximum likelihood: Extracting unbiased information from complex networks

    NASA Astrophysics Data System (ADS)

    Garlaschelli, Diego; Loffredo, Maria I.

    2008-07-01

    The choice of free parameters in network models is subjective, since it depends on what topological properties are being monitored. However, we show that the maximum likelihood (ML) principle indicates a unique, statistically rigorous parameter choice, associated with a well-defined topological feature. We then find that, if the ML condition is incompatible with the built-in parameter choice, network models turn out to be intrinsically ill defined or biased. To overcome this problem, we construct a class of safely unbiased models. We also propose an extension of these results that leads to the fascinating possibility to extract, only from topological data, the “hidden variables” underlying network organization, making them “no longer hidden.” We test our method on World Trade Web data, where we recover the empirical gross domestic product using only topological information.

  8. Insights from Preclinical Choice Models on Treating Drug Addiction.

    PubMed

    Banks, Matthew L; Negus, S Stevens

    2017-02-01

    Substance-use disorders are a global public health problem that arises from behavioral misallocation between drug use and more adaptive behaviors maintained by nondrug alternatives (e.g., food or money). Preclinical drug self-administration procedures that incorporate a concurrently available nondrug reinforcer (e.g., food) provide translationally relevant and distinct dependent measures of behavioral allocation (i.e., to assess the relative reinforcing efficacy of the drug) and behavioral rate (i.e., to assess motor competence). In particular, preclinical drug versus food 'choice' procedures have produced increasingly concordant results with both human laboratory drug self-administration studies and double-blind placebo-controlled clinical trials. Accordingly, here we provide a heuristic framework of substance-use disorders based on a behavioral-centric perspective and recent insights from these preclinical choice procedures. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Null but not void: considerations for hypothesis testing.

    PubMed

    Shaw, Pamela A; Proschan, Michael A

    2013-01-30

    Standard statistical theory teaches us that once the null and alternative hypotheses have been defined for a parameter, the choice of the statistical test is clear. Standard theory does not teach us how to choose the null or alternative hypothesis appropriate to the scientific question of interest. Neither does it tell us that in some cases, depending on which alternatives are realistic, we may want to define our null hypothesis differently. Problems in statistical practice are frequently not as pristinely summarized as the classic theory in our textbooks. In this article, we present examples in statistical hypothesis testing in which seemingly simple choices are in fact rich with nuance that, when given full consideration, make the choice of the right hypothesis test much less straightforward. Published 2012. This article is a US Government work and is in the public domain in the USA.

  10. Prenatal diagnosis and selective abortion: a challenge to practice and policy.

    PubMed Central

    Asch, A

    1999-01-01

    Professionals should reexamine negative assumptions about the quality of life with prenatally detectable impairments and should reform clinical practice and public policy to improve informed decision making and genuine reproductive choice. Current data on children and families affected by disabilities indicate that disability does not preclude a satisfying life. Many problems attributed to the existence of a disability actually stem from inadequate social arrangements that public health professionals should work to change. This article assumes a pro-choice perspective but suggests that unreflective uses of prenatal testing could diminish, rather than expand, women's choices. This critique challenges the view of disability that lies behind the social endorsement of such testing and the conviction that women will or should end their pregnancies if they discover that the fetus has a disabling trait. PMID:10553384

  11. Strategy alternatives for homeland air and cruise missile defense.

    PubMed

    Murphy, Eric M; Payne, Michael D; Vanderwoude, Glenn W

    2010-10-01

    Air and cruise missile defense of the U.S. homeland is characterized by a requirement to protect a large number of critical assets nonuniformly dispersed over a vast area with relatively few defensive systems. In this article, we explore strategy alternatives to make the best use of existing defense resources and suggest this approach as a means of reducing risk while mitigating the cost of developing and acquiring new systems. We frame the issue as an attacker-defender problem with simultaneous moves. First, we outline and examine the relatively simple problem of defending comparatively few locations with two surveillance systems. Second, we present our analysis and findings for a more realistic scenario that includes a representative list of U.S. critical assets. Third, we investigate sensitivity to defensive strategic choices in the more realistic scenario. As part of this investigation, we describe two complementary computational methods that, under certain circumstances, allow one to reduce large computational problems to a more manageable size. Finally, we demonstrate that strategic choices can be an important supplement to material solutions and can, in some cases, be a more cost-effective alternative. © 2010 Society for Risk Analysis.

  12. The choice of catecholamines in septic shock: more and more good arguments to strengthen the known position, but don't lose the faith!

    PubMed

    Meier-Hellmann, Andreas

    2006-01-01

    The choice of catecholamines for hemodynamic stabilisation in septic shock patients has been an ongoing debate for several years. Several studies have investigated the regional effects in septic patients. Because of an often very small sample size, because of inconsistent results and because of methodical problems in the monitoring techniques used in these studies, however, it is not possible to provide clear recommendations concerning the use of catecholamines in sepsis. Prospective and adequate-sized studies are necessary because outcome data are completely lacking.

  13. A Novel tool for Health Literacy: Using Comic Books to Combat Childhood Obesity.

    PubMed

    Tarver, Talicia; Woodson, Deidra; Fechter, Nick; Vanchiere, John; Olmstadt, Willam; Tudor, Charlie

    2016-01-01

    Childhood obesity remains a serious problem that requires health literacy projects to engage both parents and children in making healthy choices. This paper describes an award-funded project designed by LSU Health Shreveport (LSUHS) faculty from the Health Sciences Library and the Department of Pediatrics who created a comic book to help children and their parents learn practical ways children can make healthier lifestyle choices. LSUHS also collaborated with LSU-Shreveport to recruit a student artist, who illustrated the comic and designed promotional items used to promote the print and online versions of the book throughout the community.

  14. From brute luck to option luck? On genetics, justice, and moral responsibility in reproduction.

    PubMed

    Denier, Yvonne

    2010-04-01

    The structure of our ethical experience depends, crucially, on a fundamental distinction between what we are responsible for doing or deciding and what is given to us. As such, the boundary between chance and choice is the spine of our conventional morality, and any serious shift in that boundary is thoroughly dislocating. Against this background, I analyze the way in which techniques of prenatal genetic diagnosis (PGD) pose such a fundamental challenge to our conventional ideas of justice and moral responsibility. After a short description of the situation, I first examine the influential luck egalitarian theory of justice, which is based on the distinction between choice and luck or, more specifically, between option luck and brute luck, and the way in which it would approach PGD (section II), followed by an analysis of the conceptual incoherencies (in section III) and moral problems (in section IV) that come with such an approach. Put shortly, the case of PGD shows that the luck egalitarian approach fails to express equal respect for the individual choices of people. The paradox of the matter is that by overemphasizing the fact of choice as such, without regard for the social framework in which they are being made, or for the fundamental and existential nature of particular choices-like choosing to have children and not to undergo PGD or not to abort a handicapped fetus-such choices actually become impossible.

  15. Robust Encoding of Spatial Information in Orbitofrontal Cortex and Striatum.

    PubMed

    Yoo, Seng Bum Michael; Sleezer, Brianna J; Hayden, Benjamin Y

    2018-06-01

    Knowing whether core reward regions carry information about the positions of relevant objects is crucial for adjudicating between choice models. One limitation of previous studies, including our own, is that spatial positions can be consistently differentially associated with rewards, and thus position can be confounded with attention, motor plans, or target identity. We circumvented these problems by using a task in which value-and thus choices-was determined solely by a frequently changing rule, which was randomized relative to spatial position on each trial. We presented offers asynchronously, which allowed us to control for reward expectation, spatial attention, and motor plans in our analyses. We find robust encoding of the spatial position of both offers and choices in two core reward regions, orbitofrontal Area 13 and ventral striatum, as well as in dorsal striatum of macaques. The trial-by-trial correlation in noise in encoding of position was associated with variation in choice, an effect known as choice probability correlation, suggesting that the spatial encoding is associated with choice and is not incidental to it. Spatial information and reward information are not carried by separate sets of neurons, although the two forms of information are temporally dissociable. These results highlight the ubiquity of multiplexed information in association cortex and argue against the idea that these ostensible reward regions serve as part of a pure value domain.

  16. Cognitive models of risky choice: parameter stability and predictive accuracy of prospect theory.

    PubMed

    Glöckner, Andreas; Pachur, Thorsten

    2012-04-01

    In the behavioral sciences, a popular approach to describe and predict behavior is cognitive modeling with adjustable parameters (i.e., which can be fitted to data). Modeling with adjustable parameters allows, among other things, measuring differences between people. At the same time, parameter estimation also bears the risk of overfitting. Are individual differences as measured by model parameters stable enough to improve the ability to predict behavior as compared to modeling without adjustable parameters? We examined this issue in cumulative prospect theory (CPT), arguably the most widely used framework to model decisions under risk. Specifically, we examined (a) the temporal stability of CPT's parameters; and (b) how well different implementations of CPT, varying in the number of adjustable parameters, predict individual choice relative to models with no adjustable parameters (such as CPT with fixed parameters, expected value theory, and various heuristics). We presented participants with risky choice problems and fitted CPT to each individual's choices in two separate sessions (which were 1 week apart). All parameters were correlated across time, in particular when using a simple implementation of CPT. CPT allowing for individual variability in parameter values predicted individual choice better than CPT with fixed parameters, expected value theory, and the heuristics. CPT's parameters thus seem to pick up stable individual differences that need to be considered when predicting risky choice. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Informing health? Negotiating the logics of choice and care in everyday practices of 'healthy living'.

    PubMed

    Henwood, Flis; Harris, Roma; Spoel, Philippa

    2011-06-01

    This paper reports on a qualitative study examining everyday practices of healthy living (HL). Forty-four semi-structured interviews were undertaken with Canadian and UK citizens, aged 45 - 70, in April-May 2010. The research sits within the now substantial literature concerned with how health information is mediated, both by people and technologies, and employed in the context of 'good' health citizenship. Throughout this work, notions of 'choice' and 'empowerment' have been interrogated, theoretically and empirically, to reveal both the knowledge/power relationships integral to 'informing' processes and the shifting relationship between information and care in contemporary health encounters. In this paper, we analyse how people make sense of what it means to live healthily and how they know if they are doing so by focussing on three ways in which study participants become informed about healthy living: through their engagement with universal HL messages, through their own information searches, and through their attempts to measure their 'healthiness'. Following Mol's (2008) critique of the "logic of choice" in contemporary healthcare, we understand healthy living as a "situation of choice" where complex problems are framed as simple matters of choice and where information and technologies are understood as neutral aids to decision-making in support of 'correct' choices. Our analysis builds on and extends Mol's work by exploring how participants negotiate between this "logic of choice" and her alternative "logic of care" in their accounts of everyday HL informing practices and how the two logics "interfere" with one another. These accounts show resistance to the logic of choice through 'calls for care' but they also show clearly how the disciplining logic of choice works to (re)present such calls for care as failed attempts at healthy living, undermining the very practices the logic of choice seeks to encourage. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Performance issues for iterative solvers in device simulation

    NASA Technical Reports Server (NTRS)

    Fan, Qing; Forsyth, P. A.; Mcmacken, J. R. F.; Tang, Wei-Pai

    1994-01-01

    Due to memory limitations, iterative methods have become the method of choice for large scale semiconductor device simulation. However, it is well known that these methods still suffer from reliability problems. The linear systems which appear in numerical simulation of semiconductor devices are notoriously ill-conditioned. In order to produce robust algorithms for practical problems, careful attention must be given to many implementation issues. This paper concentrates on strategies for developing robust preconditioners. In addition, effective data structures and convergence check issues are also discussed. These algorithms are compared with a standard direct sparse matrix solver on a variety of problems.

  19. [Problem based learning: achievement of educational goals in the information and comprehension sub-categories of Bloom cognitive domain].

    PubMed

    Montecinos, P; Rodewald, A M

    1994-06-01

    The aim this work was to assess and compare the achievements of medical students, subjected to problem based learning methodology. The information and comprehension categories of Bloom were tested in 17 medical students in four different occasions during the physiopathology course, using a multiple choice knowledge test. There was a significant improvement in the number of correct answers towards the end of the course. It is concluded that these medical students obtained adequate learning achievements in the information subcategory of Bloom using problem based learning methodology, during the physiopathology course.

  20. The menu-setting problem and subsidized prices: drug formulary illustration.

    PubMed

    Olmstead, T; Zeckhauser, R

    1999-10-01

    The menu-setting problem (MSP) determines the goods and services an institution offers and the prices charged. It appears widely in health care, from choosing the services an insurance arrangement offers, to selecting the health plans an employer proffers. The challenge arises because purchases are subsidized, and consumers (or their physician agents) may make cost-ineffective choices. The intuitively comprehensible MSP model--readily solved by computer using actual data--helps structure thinking and support decision making about such problems. The analysis uses drug formularies--lists of approved drugs in a plan or institution--to illustrate the framework.

  1. Regularization by Functions of Bounded Variation and Applications to Image Enhancement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Casas, E.; Kunisch, K.; Pola, C.

    1999-09-15

    Optimization problems regularized by bounded variation seminorms are analyzed. The optimality system is obtained and finite-dimensional approximations of bounded variation function spaces as well as of the optimization problems are studied. It is demonstrated that the choice of the vector norm in the definition of the bounded variation seminorm is of special importance for approximating subspaces consisting of piecewise constant functions. Algorithms based on a primal-dual framework that exploit the structure of these nondifferentiable optimization problems are proposed. Numerical examples are given for denoising of blocky images with very high noise.

  2. Landscaping With Maintenance in Mind.

    ERIC Educational Resources Information Center

    Sorensen, Randy

    2000-01-01

    Examines school ground landscape design that enhances attractive of the school and provides for easier maintenance. Landscape design issues discussed include choice of grass, trees, and shrubs; irrigation; and safety and access. Other considerations for lessening maintenance problems for facility managers are also highlighted. (GR)

  3. Positive Health: Designs for Action.

    ERIC Educational Resources Information Center

    Beyrer, Mary K.; And Others

    This book is designed to assist young adults in making decisions regarding personal health and health behavior. Personal effectiveness, sexuality, psychoactive drugs, nutrition, disease, injury, community and environmental health, and the problems of pollution are discussed in terms of principles, choices, and risk-reduction. Discussion problems…

  4. SOLAR LIGHTING FOR REMOTE RURAL COMMUNITIES

    EPA Science Inventory

    The 132 students enrolled in the fall 2007 freshman course, “Engineering Design and Problem Solving”, were presented with a choice of five projects; one was a challenge to “Design, build and evaluate – a portable, rechargeable lantern that can be used &...

  5. Let Baby Set the Delivery Date: Wait Until 39 Weeks if You Can

    MedlinePlus

    ... the lifelong health of that baby.” Related Stories Power to the Pelvis Pregnancy and Beyond Pregnancy Problems? Milk Gland “Remembers” Past Pregnancy Wise Choices For a Healthy Pregnancy See your health care provider for regular ...

  6. Our Energy Options.

    ERIC Educational Resources Information Center

    Meyers, Paul A.; Witt, Frank C.

    Presented is an analysis of alternatives available to the United States in dealing with energy problems. Options explained and evaluated include coal, solar, hydroelectric, nuclear, geothermal, wind, biomass, and energy conservation. The booklet is part of Project APEC (America's Possible Energy Choices), a nationally validated Title IVc project…

  7. Effects of on-street parking on cyclist route choice and the operational behavior of cyclists and motorists.

    DOT National Transportation Integrated Search

    2009-04-01

    Because of the serious societal, environmental, economic, and public health problems associated with motorized : transportation, there is increased interest in encouraging non-motorized modes of travel. The current study contributes toward this : obj...

  8. Disturbances and Contradictions in an Online Conference

    ERIC Educational Resources Information Center

    Carr, Tony; Ludvigsen, Sten Runar

    2017-01-01

    This article analyses participant experiences and statements about perceived problems in two online conferences to identify tensions and disturbances relating to external factors, conference technology, online discussions and design choices and then considers the underlying contradictions within the conference systems which generate both positive…

  9. Household Schooling Behaviors and Decentralization.

    ERIC Educational Resources Information Center

    Behrman, Jere R.; King, Elizabeth M.

    2001-01-01

    Presents a simple framework for (1) demonstrating how households determine schooling investments through choice and voice; and (2) considering effects of decentralization on household behaviors, given information problems. Some aspects of decentralization may increase efficiency; others may be neutral or decrease efficiency. Further research is…

  10. Cocaine and Pregnancy

    MedlinePlus

    ... oxygen to the developing baby, even full- term newborns may have low birth weight. Cocaine may increase the risk for preterm delivery. ... breast milk following cocaine use by the mother. Newborns do not have ... your choices for breastfeeding. Is it a problem if the baby’s father ...

  11. Problems of selecting donors for artificial insemination

    PubMed Central

    Schoysman, R

    1975-01-01

    This paper is concerned with only one of the problems encountered in selecting donors for artificial insemination, that of choosing suitable donors. In Belgium medical students have generally been the donors of semen but Dr Schoysman examines the other choices of potential donors and outlines certain criteria for selecting them: these criteria are more explicit than those outlined by Professor Kerr and Miss Rogers on page 32. He also touches on the question of payment to donors. PMID:1165573

  12. Coping with the Usual Family Diet: Eating Behaviour and Food Choices of Children with Down's Syndrome, Autistic Spectrum Disorders or Cri du Chat Syndrome and Comparison Groups of Siblings.

    ERIC Educational Resources Information Center

    Collins, Margaret S. R.; Kyle, Rosalind; Smith, Suzanne; Laverty, Anne; Roberts, Sylvia; Eaton-Evans, Jill

    2003-01-01

    A study of 405 Irish children (ages 2-18) with Down syndrome, autism, and cri du chat syndrome, and 280 siblings found most had some level of self-feeding skills. Chewing problems were reported for some children, including siblings of children with Down syndrome and autism. Behavioral problems at meals were common. (Contains references.)…

  13. Examining Parents' Preferences for Group and Individual Parent Training for Children with ADHD Symptoms.

    PubMed

    Wymbs, Frances A; Cunningham, Charles E; Chen, Yvonne; Rimas, Heather M; Deal, Ken; Waschbusch, Daniel A; Pelham, William E

    2016-01-01

    Parent training (PT) programs have been found to reduce some behavioral impairment associated with children's attention deficit hyperactivity disorder (ADHD) as well as improve parenting competence, but poor uptake and participation by parents are formidable barriers that affect service effectiveness. We used a discrete-choice experiment (DCE) to examine how parent preferences for treatment format (i.e., group vs. individual) might influence their participation in PT. Participants were 445 parents seeking mental health services for children with elevated symptoms of ADHD in Ontario, Canada. Parents completed a DCE composed of 30 choice tasks used to gauge PT format preference. Results showed that 58.7% of parents preferred individual PT; these parents were most interested in interventions that would make them feel more informed about their child's problems and in understanding-as opposed to solving-their child's problems. A minority of parents (19.4%) preferred group PT; these parents were most interested in active, skill-building services that would help them solve their child's problems. About one fifth of parents (21.9%) preferred the Minimal Information alternative (i.e., receiving neither individual or group PT); these parents reported the highest levels of depression and the most severe mental health problems in their child. Results highlight the importance of considering parent preferences for format and suggest that alternative formats to standard PT should be considered for multiply stressed families.

  14. Intertemporal Choice Behavior in Emerging Adults and Adults: Effects of Age Interact with Alcohol Use and Family History Status

    PubMed Central

    Smith, Christopher T.; Steel, Eleanor A.; Parrish, Michael H.; Kelm, Mary K.; Boettiger, Charlotte A.

    2015-01-01

    Adults with alcohol use disorders (AUDs) show marked immediate reward selection (or “Now”) bias in intertemporal choice tasks. This Now bias persists long into abstinence, suggesting an irreversible consequence of chronic alcohol abuse or a pre-existing AUD intermediate phenotype. However, some data show substantial Now bias among emerging adults (18–25), regardless of drinking behavior, suggesting age-dependent effects on Now bias. The objectives of the present study were to determine (1) whether Now bias is greater among emerging adults relative to adults, (2) whether any such age effect on Now bias is diminished in sub-clinical heavy alcohol users, and (3) whether having a problem drinking first degree relative is independently associated with elevated Now bias. To achieve these objectives, we used an intertemporal choice task to quantify Now bias in n = 237 healthy participants (ages 18–40; 50% female), and a wide range of non-zero alcohol use, based on the Alcohol Use Disorders Identification Test (AUDIT). We found that among non-heavy drinkers, Now bias inversely correlated with age; this relationship was not present among heavy drinkers. We found no significant relationship between AUDIT score and Now bias among emerging adults, but AUDIT scores and Now bias were positively correlated among 26–40 year olds. Additionally, non-heavy drinking adults who reported a problem drinking first degree relative showed greater Now bias compared to those not reporting familial problem drinking. While not definitive, these findings lend support for elevated Now bias in adulthood as an intermediate phenotype for AUDs. Moreover, non-additive effects of age and heavy drinking on Now bias suggest perturbations in largely common neural circuits in both groups. PMID:26635580

  15. Measuring rural women's work and class position.

    PubMed

    Deere, C D; León de Leal, M

    1979-01-01

    On the basis of experience gained in researching the economic roles of rural women in a national level study in Colombia and in a regional level study in Peru, some of the methodological problems of measuring rural women's economic participation by sample survey are considered. The specific objective of the sample surveys was to quantify the existing sexual division of labor among the peasant population. The rural household was the unit of analysis, and the focus of measurement was the division of labor by sex in such activities as daily maintenance, household production, and income-generating activitives pursued outside the household. The focus of the survey questionnaire is on the sexual division of labor, but it necessarily must be related to another series of socioeconomic or cultural variables for analysis. The selection of these variables needs to be derived from the hypotheses guiding the study, yet much attention must be given to narrowing the range of inquiry. The time constraint on the length of the questionnaire requires that certain choices be made in terms of the complementary variables to be included. The most important problem in the design of a representative sample survey is the selection of the population to be sampled. The choice of population needs to be compatible with the theoretical framework. Since the interest was to measure the sexual division of labor in terms of class formation, the sample had to be representative of the different class strata in the rural areas. The measurement of access to means of production ideally should be quantitative and qualitative. The choice of the population to be sampled is also constrained by the available data base, a particular problem in rural areas.

  16. Impact of a decision aid on surrogate decision-makers' perceptions of feeding options for patients with dementia.

    PubMed

    Snyder, E Amanda; Caprio, Anthony J; Wessell, Kathryn; Lin, Feng Chang; Hanson, Laura C

    2013-02-01

    In advanced dementia, feeding problems are nearly universal, and families face difficult decisions about feeding options. Initial interviews for a randomized trial were used to describe surrogates' perceptions of feeding options, and to determine whether a decision aid on feeding options in advanced dementia would improve knowledge, reduce expectation of benefit from tube feeding, and reduce conflict over treatment choices for persons with advanced dementia. Semistructured interview with prestudy and poststudy design for surrogates in the intervention group. Twenty-four skilled nursing facilities across North Carolina participating in a cluster randomized trial. Two hundred and fifty-five surrogate decision makers for nursing home residents with advanced dementia and feeding problems, in control (n = 129) and intervention (n = 126) groups. For intervention surrogates only, an audiovisual-print decision aid provided information on dementia, feeding problems in dementia, advantages and disadvantages of feeding tubes or assisted oral feeding options, and the role of surrogates in making these decisions. The interview included open-ended items asking surrogates to report advantages and disadvantages of tube feeding and assisted oral feeding. Knowledge of feeding options was measured with 19 true/false items and items measuring expectation of benefit from tube feeding. Surrogates reported which of these two feeding options they preferred for the person with dementia, and how confident they were in this choice; their level of conflict about the choice was measured using the decisional conflict scale. Before the decision aid, surrogates described advantages and disadvantages of assisted oral feeding and tube feeding in practical, ethical, and medical terms. After review of the decision aid, intervention surrogates had improved knowledge scores (15.5 vs 16.8; P < .001), decreased expectation of benefits from tube feeding (2.73 vs 2.32; P = .001), and reduced decisional conflict (2.24 vs 1.91; P < .001). Surrogates preferred assisted oral feeding initially and reported more certainty about this choice after the decision aid. A structured decision aid can be used to improve decision making about feeding options in dementia care. Copyright © 2013 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

  17. Impact of a Decision Aid on Surrogate Decision-makers’ Perceptions of Feeding Options for Patients with Dementia

    PubMed Central

    Snyder, E. Amanda; Caprio, Anthony J.; Wessell, Kathryn; Lin, Feng Chang; Hanson, Laura C.

    2012-01-01

    Objective In advanced dementia, feeding problems are nearly universal, and families face difficult decisions about feeding options. Initial interviews for a randomized trial were used to describe surrogates’ perceptions feeding options, and to determine if a decision aid on feeding options in advanced dementia would improve knowledge, reduce expectation of benefit from tube feeding, and reduce conflict over treatment choices for persons with advanced dementia. Design Semi-structured interview with pre-post study design for surrogates in the intervention group. Setting Twenty-four skilled nursing facilities across North Carolina participating in a cluster randomized trial. Participants Two hundred fifty-five surrogate decision-makers for nursing home residents with advanced dementia and feeding problems, in control (n=129) and intervention (n=126) groups. Intervention For intervention surrogates only, an audiovisual-print decision aid provided information on dementia, feeding problems in dementia, advantages and disadvantages of feeding tubes or assisted oral feeding options and the role of surrogates in making these decisions. Measurements The interview included open-ended items asking surrogates to report advantages and disadvantages of tube feeding and assisted oral feeding. Knowledge of feeding options was measured with 19 true-false items, and items measuring expectation of benefit from tube feeding. Surrogates reported which of these two feeding options they preferred for the person with dementia, and how confident they were in this choice; their level of conflict about the choice was measured using the Decisional Conflict Scale. Results Prior to the decision aid, surrogates described advantages and disadvantages of assisted oral feeding and tube feeding in practical, ethical and medical terms. After review of the decision aid, intervention surrogates had improved knowledge scores (15.5 vs. 16.8; p<0.001), decreased expectation of benefits from tube feeding (2.73 vs. 2.32; p = 0.001) and reduced decisional conflict (2.24 vs. 1.91, p<0.001). Surrogates preferred assisted oral feeding initially, and reported more certainty about this choice after the decision aid. Conclusion A structured decision aid can be used to improve decision-making about feeding options in dementia care. PMID:23273855

  18. Equity, autonomy, and efficiency: what health care system should we have?

    PubMed

    Menzel, Paul T

    1992-02-01

    The U.S. has a wide range of options in choosing a health care system. Rational choice of a system depends on analysis and prioritization of the basic moral goals of equitable access to all citizens, the just sharing of financial costs between well and ill, respect for the values and choices of subscribers and patients, and efficiency in the delivery of costworthy care. These moral goals themselves, however, tell us little about what health care system the United States should have. Equitable access does not demand a level and scope of care for the poor equal to that rationally chosen by the middle class, and there are ways within mixed systems, though not easy ways, to achieve a fair distribution of costs between well and ill. Despite pluralistic systems' apparent advantage in allowing subscribers to choose their own forms of rationing, problems in translating serious long-term subscriber choices into actual medical practice may be greater in pluralistic than in unitary systems. Final choice of a system hinges primarily on peculiar historical facts about U.S. political culture, not on moral principle.

  19. Equality, autonomy, and efficiency: what health care system should we have?

    PubMed

    Menzel, P T

    1992-02-01

    The U.S. has a wide range of options in choosing a health care system. Rational choice of a system depends on analysis and prioritization of the basis moral goals of equitable access to all citizens, the just sharing of financial costs between well and ill, respect for the values and choices of subscribers and patients, and efficiency in the delivery of costworthy care. These moral goals themselves, however, tell us little about what health care system the United States should have. Equitable access does not demand a level and scope of care for the poor equal to that rationally chosen by the middle class, and there are ways within mixed systems, though not easy ways, to achieve a fair distribution of costs between well and ill. Despite pluralistic systems' apparent advantage in allowing subscribers to choose their own forms of rationing, problems in translating serious long-term subscriber choices into actual medical practice may be greater in pluralistic than in unitary systems. Final choice of a system hinges primarily on peculiar historical facts about U.S. political culture, not on moral principle.

  20. Decisions in Motion: Decision Dynamics during Intertemporal Choice reflect Subjective Evaluation of Delayed Rewards

    PubMed Central

    O’Hora, Denis; Carey, Rachel; Kervick, Aoife; Crowley, David; Dabrowski, Maciej

    2016-01-01

    People tend to discount rewards or losses that occur in the future. Such delay discounting has been linked to many behavioral and health problems, since people choose smaller short-term gains over greater long-term gains. We investigated whether the effect of delays on the subjective value of rewards is expressed in how people move when they make choices. Over 600 patrons of the RISK LAB exhibition hosted by the Science Gallery DublinTM played a short computer game in which they used a computer mouse to choose between amounts of money at various delays. Typical discounting effects were observed and decision dynamics indicated that choosing smaller short-term rewards became easier (i.e., shorter response times, tighter trajectories, less vacillation) as the delays until later rewards increased. Based on a sequence of choices, subjective values of delayed outcomes were estimated and decision dynamics during initial choices predicted these values. Decision dynamics are affected by subjective values of available options and thus provide a means to estimate such values. PMID:26867497

Top