Group choice: the ideal free distribution of human social behavior

Group choice refers to the distribution of group members between two choice alternatives over time. The ideal free distribution (IFD), an optimal foraging model from behavioral ecology, predicts that the ratio of foragers at two resource sites should equal the ratio of obtained resources, a prediction that is formally analogous to the matching law of individual choice, except that group choice is a social phenomenon. Two experiments investigated the usefulness of IFD analyses of human group choice and individual-based explanations that might account for the group-level events. Instead of nonhuman animals foraging at two sites for resources, a group of humans chose blue and red cards to receive points that could earn cash prizes. The groups chose blue and red cards in ratios in positive relation to the ratios of points associated with the cards. When group choice ratios and point ratios were plotted on logarithmic coordinates and fitted with regression lines, the slopes (i.e., sensitivity measures) approached 1.0 but tended to fall short of it (i.e., undermatching), with little bias and little unaccounted for variance. These experiments demonstrate that an IFD analysis of group choice is possible and useful, and suggest that group choice may be explained by the individual members' tendency to optimize reinforcement.     

中国古代心理学思想中的注意问题

本文根据古代思想家的有关言论,探讨了他们的注意心理思想,即注意的慨念。特征,分心与分散,分配与集中,注意与感知、记忆、思维的关系,注意在学习中的作用。     

A Unified Approach to Power Calculation and Sample Size Determination for Random Regression Models

The underlying statistical models for multiple regression analysis are typically attributed to two types of modeling: fixed and random. The procedures for calculating power and sample size under the fixed regression models are well known. However, the literature on random regression models is limited and has been confined to the case of all variables having a joint multivariate normal distribution. This paper presents a unified approach to determining power and sample size for random regression models with arbitrary distribution configurations for explanatory variables. Numerical examples are provided to illustrate the usefulness of the proposed method and Monte Carlo simulation studies are also conducted to assess the accuracy. The results show that the proposed method performs well for various model specifications and explanatory variable distributions. The author would like to thank the editor, the associate editor, and the referees for drawing attention to pertinent references that led to improved presentation. This research was partially supported by National Science Council grant NSC-94-2118-M-009-004.     

Delta图分析方法及其在冲突控制研究中的应用

近年来,反应时分布分析方法被应用于冲突控制研究领域,以弥补只计算平均反应时和错误率的不足。所谓delta指的是不一致条件与一致条件反应时之差,即冲突效应量。冲突效应量随反应时间的变化图称为delta图。与该分析方法相应的理论模型包括双通路模型和激活－抑制模型。本文介绍了delta图分析的具体方法及其与冲突控制理论模型的关系,然后列举了有关的研究例证,并强调了其优缺点与适用范围     

Task difficulty and inertial properties of hand-held tools: An assessment of their concurrent effects on precision aiming

Aiming hand-held tools at targets in space entails adjustments in the dynamical organization of aiming patterns according to the required precision. We asked whether and how these adjustments are modified by the tool’s mass distribution. Twelve participants performed reciprocal aiming movements with a 50-cm long wooden probe. Kinematic patterns of probe movements were used as a window into the behavioral dynamic underlying performance of a reciprocal aiming task. We crossed three levels of task difficulty (IDs 2.8, 4.5 and 6.1) with two types of probe varying in their mass distribution (proximal vs distal loading). Movement duration was affected by task difficulty and probe loading (shorter for larger targets and proximal probe loading). Progressive deviations from a sinusoidal movement pattern were observed as task difficulty increased. Such deviations were more pronounced with proximal probe loading. Results point to a higher degree of non-linearity in aiming dynamics when the probe was loaded proximally, which might reflect employment of additional perceptual-motor processes to control the position of its less stable tip at the vicinity of the targets. More generally, the effects of probe loading on aiming pattern and dynamics suggest that perceptual-motor processes responding to task level constraints are sensitive to, and not independent from, biomechanical, end-effector constraints.     

Why Bayesian Psychologists Should Change the Way They Use the Bayes Factor

The discussion following Bem’s (2011 Bem, D. J. (2011). Feeling the future: Experimental evidence for anomalous retroactive influences on cognition and affect. Journal of Personality and Social Psychology, 100, 407–425. doi: 10.1037/a0021524[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) psi research highlights that applications of the Bayes factor in psychological research are not without problems. The first problem is the omission to translate subjective prior knowledge into subjective prior distributions. In the words of Savage (1961 Savage, L. J. (1961). The foundations of statistical inference reconsidered. In J. Neyman, (Ed.), Proceedings of the Fourth Berkeley Symposium on Mathematical Statistics and Probability, Volume 1: Contributions to the Theory of Statistics, pp. 575–586. BerkeleyCA: University of California. [Google Scholar]): “they make the Bayesian omelet without breaking the Bayesian egg.” The second problem occurs if the Bayesian egg is not broken: the omission to choose default prior distributions such that the ensuing inferences are well calibrated. The third problem is the adherence to inadequate rules for the interpretation of the size of the Bayes factor. The current paper will elaborate these problems and show how to avoid them using the basic hypotheses and statistical model used in the first experiment described in Bem (2011 Bem, D. J. (2011). Feeling the future: Experimental evidence for anomalous retroactive influences on cognition and affect. Journal of Personality and Social Psychology, 100, 407–425. doi: 10.1037/a0021524[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). It will be argued that a thorough investigation of these problems in the context of more encompassing hypotheses and statistical models is called for if Bayesian psychologists want to add a well-founded Bayes factor to the tool kit of psychological researchers.     

Tactile order memory: evidence for sequence learning phenomena found with other stimulus types

We examine serial order memory for sequences of tactile stimuli and investigate whether established characteristics of order memory, namely serial position effects, error distributions, and Hebb repetition learning, are observed with tactile memory. Visually obscured participants received six tactile stimulations: one to each of six fingers. At test, participants lifted the six fingers in the order of stimulation. For every third trial participants received the same order of stimulation (i.e. the Hebb sequence). Serial recall accuracy produced the canonical bowed serial position function found for immediate serial recall. In addition, recall for the Hebb sequence improved relative to the filler sequences, providing the first demonstration of the Hebb repetition effect with tactile stimuli. Analysis of errors revealed close similarities to that reported with verbal and visual stimuli. This experiment further generalises established features of order memory to tactile memory, supporting the utilisation of an analogous order memory mechanism across stimuli.     

Evidence for Mixed Processes in Normal/Mirror Discrimination of Rotated Letters: A Bayesian Model Comparison Between Single- and Mixed-Distribution Models1

When determining whether a rotated letter is normal or mirrored, an observer mentally rotates the letter to its canonical orientation. To account for patterns of response times (RTs) for the normal/mirror discrimination of rotated letters, previous research formulated a model that postulated a mixture of trials with and without mental rotation. While this model could explain the curvilinear relationship that has been found between averaged RT and letter orientations, the curved RT function is still open to alternative explanations without assuming mixed processes. To address this issue and test the mixed-process hypothesis more directly, we analyzed trial-by-trial RT data instead of averaged RTs by employing a Bayesian model comparison technique. If rotation and non-rotation trials are mixed, trial-by-trial RTs for letters in a particular orientation should not follow a single distribution but a mixed one formed from the superposition of two separate distributions, one for rotation and one for non-rotation trials. In the present study, we compared single- and mixed-distribution models. Bayes-factor analysis showed decisive support for the mixed-distribution model over the single-distribution model. In addition, using the widely applicable information criterion (WAIC), the predictive accuracy of the mixed-distribution model was found to be as high as that of the single-distribution model. These results indicated the involvement of mixed processes in normal/mirror discrimination of rotated letters. The usefulness of statistical modeling in psychological study and necessary precautions to take in the interpretation of the parameters of unconfirmed models are also discussed.     

Evolution of grain-boundary character distribution during iterative processing of an austenitic stainless steel

The present article deals with the analysis of grain-boundary character distribution (GBCD) and microstructural characteristics after iterative processing of austenitic stainless steel, AISI 316L. The steel was subjected to iterative cold reduction and subsequent annealings. After an initial decrease in the fraction of Σ3 boundaries, the number of these increases in subsequent steps. The results relate the importance of iterative processing and the mechanism of obtaining a higher fraction of Σ3 boundaries.     

The phenomenology and temporal distributions of autobiographical memories elicited with emotional and neutral cue words

In this study we examined whether the temporal distribution of autobiographical memory changes when different types of cue words are used to elicit the memories, and how the type of cue word affects the phenomenal characteristics of the memories. A total of 76 participants, ranging in age from 21 to 69 years, were presented with 22 cue words (emotional, emotion-provoking, and neutral). They were asked to recall a personal event and to complete the Autobiographical Memory Questionnaire (Rubin, Schrauf, & Greenberg, 2003, 2004) for each cue word. Results showed that the phenomenological properties of autobiographical memories which were cued with emotional and emotion-provoking words were rated higher than those of memories which were cued with neutral words, and that the peak in the temporal distributions of the autobiographical memories that were cued with emotional or emotion-provoking words were located later than the peak of the distribution of the memories that were cued with neutral words.