When the best appears to be saved for last: Serial position effects on choice

Decision‐makers often evaluate options sequentially due to constraints on attention, timing, or physical location of the options. Choosing the best option will therefore often depend on people's memories of the options. Because imperfect recall introduces uncertainty in earlier options, judgments of those options should regress toward the category mean as memory decays over time. Relatively desirable options will therefore tend to seem less desirable with time, and relatively undesirable options will tend to seem less undesirable with time. We therefore predicted that people will tend to select the first option in a set when choosing between generally undesirable options, and will tend to select the last when choosing between generally desirable options. We demonstrate these serial position effects in choices among paintings, American Idol audition clips, jellybeans, and female faces, provide evidence of its underlying mechanism, and explain how these findings build on existing accounts. Copyright © 2009 John Wiley & Sons, Ltd.     

The effects of TV commercials using less thin models on young women's mood, body image and actual food intake

This study experimentally tested the effects of exposure to television commercials using less thin models on mood, body focused anxiety and food intake, as compared to the effects of commercials using thin models. In a naturalistic setting, 110 young women were exposed to a neutral movie, interrupted by two commercial breaks. The commercial breaks contained real commercials using either less thin (n = 32) or thin models (n = 39), or neutral commercials (n = 39). During watching television, participants could freely eat snack food. Further, their mood and body focused anxiety was assessed. ANOVAs revealed no effects on body focused anxiety, but women reported a more negative mood and ate less after exposure to commercials using less thin models than after exposure to commercials using thin models. These results imply that using less thin models in commercials explicitly referring to the thin ideal does not make women feel better.     

适用于多维迫选测验的IRT计分模型

迫选(forced-choice,FC)测验由于可以控制传统李克特方法带来的反应偏差,被广泛应用于非认知测验中,而迫选测验的传统计分方式会产生自模式数据,这种数据由于不适合于个体间的比较,一直备受批评。近年来,多种迫选IRT模型的发展使研究者能够从迫选测验中获得接近常模性的数据,再次引起了研究者与实践人员对迫选IRT模型的兴趣。首先,依据所采纳的决策模型和题目反应模型对6种较为主流的迫选IRT模型进行分类和介绍。然后,从模型构建思路、参数估计方法两个角度对各模型进行比较与总结。其次,从参数不变性检验、计算机化自适应测验(computerized adaptive testing, CAT)和效度研究3个应用研究方面进行述评。最后提出未来研究可以在模型拓展、参数不变性检验、迫选CAT测验和效度研究4个方向深入。     

因果与权重：决策的眼动模型

结合眼动注视的漂移扩散模型可较好描述个体的决策行为,但尚存两个问题未得解决：注视与决策的因果关系以及决策过程中累积证据的权重问题。本研究采用基于注视的操纵范式考察了基于价值的决策中注视与决策的关系,发现操纵被试对选项的注视时间可影响其选择,注视操纵主要影响决策后期时程,且模型参数估计结果更支持近因模型。研究结果支持了漂移扩散模型的近因假设,为今后的模型发展指明了新方向。     

EXPERIENCING AND INTERPRETING NATURE IN SCIENCE AND RELIGION

Abstract. I trace three paths from nature to religious interpretation. The first starts from religious experience in the context of nature; examples are drawn from nature poets, reflective scientists, and exponents of creation spirituality. The second,„Natural Theology”uses scientific findings concerning cosmology or evolution to develop an argument from design–or alternatively to defend evolutionary naturalism. The third,„Theology of Nature”starts from traditional religious beliefs about God and human nature and reformulates them in the light of current science. I point to examples of each of these paths in papers by other participants in this symposium, and suggest that all three paths can contribute to the task of relating science and religion today.     

The effect of variable delays on self-control

Five pigeons served as subjects in an experiment that examined the effects of variable as opposed to fixed delays on preference in a self-control paradigm (choice between larger, more delayed and smaller, less delayed reinforcers). Nonindependent concurrent variable-interval schedules were used to measure choice. When delays to the larger, more delayed reinforcers were variable as opposed to fixed, the subjects showed an increased preference for that alternative (the self-control alternative). A series of regressions revealed that the hyperbolic decay model and incentive theory provided poor fits to the data, but a modified version of the generalized matching law provided an adequate fit. Together, consistent with a general prediction made by discounting models, the data supported the conclusion that variable delays can increase self-control. However, specific discounting models were not able to explain the present data well.     

Leaving patches: Effects of travel requirements

Five pigeons were trained in an analogue foraging procedure in which, by completing a travel requirement, they entered a “patch” in which a reinforcer might be available after an unpredictable time. They also had the opportunity, by emitting a defined response, to exit the patch and travel to another patch. Prey availability in a patch was not signaled. Data were collected on the length of time that subjects stayed in patches before exiting (residence times) as a function of various travel requirements: travel for a fixed time in blackout, fixed-interval schedule traveling, fixed-time traveling with an added response required to terminate traveling, and fixed-ratio traveling. For each of these conditions, the required amount of travel (time or responses) was varied over a wide range. As previously reported, residence times increased with increases in fixed-time traveling, as they did with increasing fixed-interval or fixed-ratio traveling. There was no evidence that adding response or work requirements systematically affected residence time except via increased travel time, although 3 of the 5 birds stayed longer in a patch under higher fixed-ratio values. A “threshold-maximization” model described the data well with a single parameter that was consistent across subjects, procedures, and experiments.     

Choice between reliable and unreliable reinforcement alternatives revisited: Preference for unreliable reinforcement

Pigeons' choices between a reliable alternative that always provided food after a delay (i.e., 100% reinforcement) and an unreliable one that provided food or blackout equally often after a delay (i.e., 50% reinforcement) was studied using a discrete-trials concurrent-chains procedure modified to prevent choice between alternatives following a blackout outcome. Initial links were fixed-ratio 1 schedules, and terminal links were fixed-time schedules. Stimuli presented during the terminal-link delays were correlated with the food and blackout outcomes. In Experiment 1, terminal-link durations were varied. With short terminal links (i.e., 10 s), 6 of 8 subjects showed strong preference for the 50% side. As terminal-link duration increased to 30 s, preference, regardless of direction, became less extreme. In Experiment 2, the side-key location of the 50% and 100% alternatives was reversed for 3 subjects. Preference for the 50% alternative reoccurred following the key reversal. When a 5-s separation was subsequently interposed between the initial and terminal links for both alternatives, all birds reversed to a preference for the 100% side. In general, the strong preference for the 50% side was qualitatively consistent with the expectation that the procedure enhanced the conditioned-reinforcement effectiveness of the food-associated terminal-link stimulus on the 50% side. Implications of the results for various accounts of choice of the 50% alternative are discussed.     

Simple additivity of stochastic psychological processes: Tests and measures

In this article, some additive models of behavioral measures are defined, and distributional tests of them are proposed. Major theoretical results include (a) conditions for additivity of components to predict the highest level of dominance in a model-free stochastic dominance hierarchy, (b) methods of identifying the shape of the hazard rate function of an added component from certain relationships among the observable density and distribution functions, and (c) effects of stochastic dependence between components on the distributional tests. Feasibility and usefulness of the methods are demonstrated by application to choice RT and ratings experiments.The author was supported by grants MH44640 to Roger Ratcliff and AFOSR 90-0246 (jointly funded by NSF) to Gail McCoon. Parts of this work were presented at the European Mathematical Psychology meetings of 1991. My thanks to F. Gregory Ashby, Bruce Bloxom, Roger Ratcliff, W. Schwarz, Jim Townsend, and an anonymous reviewer for their many helpful suggestions.     

The origins and function of the reference point in risky group decision making the case of the Cuban missile crisis

This case study explores reference level effects on group decision making during the Cuban missile crisis of 1962. The group is composed of American President John F. Kennedy and his advisers. The results are consistent with much experimental evidence showing that reference levels play an important role in determining preferences. The results also extend the notion of reference-dependent risky choice to the group level, where the group consists of seasoned experts who each have a different role to play within the group and who are dealing with an issue of great importance.