A local model of concurrent performance

Concurrent procedures may be conceptualized as consisting of two pairs of schedules with only one pair operating at a time. One schedule of each pair arranges reinforcers for staying in the current alternative, and the other schedule arranges reinforcers for switching to the other alternative. These pairs alternate operation as the animal switches between choices. This analysis of the contingencies suggests that variables operating within an alternative produce behavior that conforms to the generalized matching law. Rats were exposed to one pair of stay and switch schedules in each condition, and the probabilities of reinforcement varied across conditions. Both run length and visit duration were power functions of the ratio of the probabilities of reinforcement for staying and switching. The local model, a model of performance on concurrent procedures, was derived from this power function. Performance on concurrent schedules was synthesized from the performances on the separate pairs. Both the generalized matching law and the local model fitted the synthesized concurrent performances. These results are consistent with the view that the contingencies in the alternative, the probability of stay and switch reinforcement, are responsible for performance consistent with the generalized matching law. These results are compatible with momentary maximizing and molar maximizing accounts of concurrent performance. Models of concurrent performance that posit comparisons among the alternatives are not easily applied to these results.     

Distractor effect on the latent inhibition of conditioned flavor aversion in rats

Using a conditioned flavor aversion procedure with rats as subjects, the effect of the addition of a distractor stimulus on the magnitude of the latent inhibition effect was examined. Experiment 1 showed that latent inhibition to vinegar was attenuated by the addition of sucrose during preexposure. On the other hand, sucrose added during conditioning to vinegar did not attenuate latent inhibition. It was also found that the degree of latent inhibition to the vinegar-sucrose compound solution was less when vinegar alone was preexposed (i.e., when sucrose was added only during conditioning) than when the compound solution was preexposed (i.e., when sucrose was added both during preexposure and during conditioning). Experiment 2 gave similar results but with sucrose assigned as the target flavor and vinegar as the distractor. These findings are in full agreement with the generalization decrement account of latent inhibition.     

Bayesian estimation and testing of structural equation models

The Gibbs sampler can be used to obtain samples of arbitrary size from the posterior distribution over the parameters of a structural equation model (SEM) given covariance data and a prior distribution over the parameters. Point estimates, standard deviations and interval estimates for the parameters can be computed from these samples. If the prior distribution over the parameters is uninformative, the posterior is proportional to the likelihood, and asymptotically the inferences based on the Gibbs sample are the same as those based on the maximum likelihood solution, for example, output from LISREL or EQS. In small samples, however, the likelihood surface is not Gaussian and in some cases contains local maxima. Nevertheless, the Gibbs sample comes from the correct posterior distribution over the parameters regardless of the sample size and the shape of the likelihood surface. With an informative prior distribution over the parameters, the posterior can be used to make inferences about the parameters underidentified models, as we illustrate on a simple errors-in-variables model.We thank David Spiegelhalter for suggesting applying the Gibbs sampler to structural equation models to the first author at a 1994 workshop in Wiesbaden. We thank Ulf Böckenholt, Chris Meek, Marijtje van Duijn, Clark Glymour, Ivo Molenaar, Steve Klepper, Thomas Richardson, Teddy Seidenfeld, and Tom Snijders for helpful discussions, mathematical advice, and critiques of earlier drafts of this paper.     

The Recruitment of Shifting and Inhibition in On‐line Science and Mathematics Tasks

Prior research has investigated the recruitment of inhibition in the use of science/mathematics concepts in tasks that require the rejection of a conflicting, nonscientific initial concept. The present research examines if inhibition is the only EF skill recruited in such tasks and investigates whether shifting is also involved. It also investigates whether inhibition and/or shifting are recruited in tasks in which the use of science/mathematics concepts does not require the rejection of an initial concept, or which require only the use of initial concepts. One hundred and thirty‐three third‐ and fifth‐grade children participated in two inhibition and shifting tasks and two science and mathematics conceptual understanding and conceptual change (CU&C) tasks. All the tasks were on‐line, and performance was measured in accuracy and RTs. The CU&C tasks involved the use of initial concepts and of science/mathematics concepts which required conceptual changes for their initial formation. Only in one of the tasks the use of the science/mathematics concepts required the concurrent rejection of an initial concept. The results confirmed that in this task inhibition was recruited and also showed that the speed of shifting was a significant predictor of performance. Shifting was a significant predictor of performance in all the tasks, regardless of whether they involved science/mathematics or initial concepts. It is argued that shifting is likely to be recruited in complex tasks that require multiple comparisons of stimuli and the entertainment of different perspectives. Inhibition seems to be a more selective cognitive skill likely to be recruited when the use of science/mathematics concepts requires the rejection of a conflicting initial concept.     

Subtypes of severe psychological distress among US Air Force remote warriors: A latent class analysis

US Air Force remote warrior personnel include a range of military personnel composed of remotely piloted aircraft aircrew, intelligence operators, and cyber warfare operators. Job duties in these professions entail long work hours, rotating shifts, and regular engagement in combat operations. Although research has identified a number of factors correlated with elevated burnout and emotional distress in this population, little is known about the unique needs of discrete subgroups of distressed personnel. In a sample of 7,550 US Air Force remote warriors, results of latent class analysis yielded four distinct classes. Three of the four reported moderately elevated burnout and job dissatisfaction but differed with respect to demographics and development career stage. The fourth group reported significantly higher levels of emotional distress, burnout, job dissatisfaction, and problems in living. This latter group was comparable to the mid-career group with respect to demographics, although this group had much lower levels of responsibility and indicators of career advancement. Results suggest that, among remote warrior personnel, there are several subtypes of elevated emotional distress. Prevention and intervention strategies that are matched to each subtype may yield better occupational and mental health outcomes than universal, “one size fits all” strategies.     

Predicting elections from the most important issue: A test of the take‐the‐best heuristic

We used the take‐the‐best heuristic to develop a model to forecast the popular two‐party vote shares in U.S. presidential elections. The model draws upon information about how voters expect the candidates to deal with the most important issue facing the country. We used cross‐validation to calculate a total of 1000 out‐of‐sample forecasts, one for each of the last 100 days of the ten U.S. presidential elections from 1972 to 2008. Ninety‐seven per cent of forecasts correctly predicted the winner of the popular vote. The model forecasts were competitive compared to forecasts from methods that incorporate substantially more information (e.g., econometric models and the Iowa Electronic Markets). The purpose of the model is to provide fast advice on which issues candidates should stress in their campaign. Copyright © 2010 John Wiley & Sons, Ltd.     

论《周易参同契》的“变形而仙”说

魏伯阳所撰《周易参同契》是运用《周易》原理来支撑金丹之道的滥觞。它以《周易》的变易原理作为道教神仙存在学说的理论基础,通过论说"物性可变",进而说明人也可变。人通过服炼金丹能够变化自己的身体而为神仙之体,即"変形而仙",从而可以超越生死。"变形而仙"思想并非《参同契》独创,而是有所本的。这一思想对后世道教产生了巨大而深远的影响,如葛洪、陶弘景、沈汾等人皆明显继承了《参同契》的"变形而仙"说。     

组织变革背景下团队主动性的结构与测量

旨在探索组织变革背景下团队主动性行为的结构,并开发出相应的测量工具。首先对20家企业的27位高管进行了深度访谈,然后按照扎根理论思路对获取资料进行细致分析,探索团队主动性的结构,再按照严格的心理测量学程序开发团队主动性的测量问卷,并以来自60家企业的70个团队（共292位成员）为对象进行了测验。研究发现：团队主动性的主要维度包括群策、协作和适应。经过探索性因素分析和验证性因素分析,结果表明测量工具有着良好的信度和构思效度。     

Chinese college students' general and relationship‐specific representations of adult attachment: Variable‐centred and person‐centred analysis

Formerly, researchers often treated adult attachment as a trait‐like construct with consistency across relationship contexts. However, recent studies have shown that people possess multiple relationship‐specific attachment representations, and inter‐correlations among them are only in a small‐to‐medium range. The aim of this study is to test whether these variable‐centred results could be replicated in China and further supplement them with a person‐centred analysis focusing on identifying prototypical patterns of multiple working models across relationships. We administrated measurements of general and four relationship‐specific (mother/father/best friend/romantic partner) working models and indicators of psychological adjustment upon 302 Chinese college students. Results from variable‐centred analysis demonstrated the cross‐relationship variability in working models. Furthermore, global indicators of psychological adjustment were better predicted by general models, while relationship‐specific indicators were better predicted by corresponding relationship‐specific models. These results largely replicate previous Western studies, supporting the existence of multiple attachment representations in China. In person‐centred analysis, a latent profile analysis identified four typical classes of working model profiles: all‐average, all‐secure, romantic‐insecure and peer‐secure. These classes differed not only in the cross‐relationship variability of their working models, but also in their levels of psychological adjustment. These interesting patterns may have theoretical implications and are worthy of further examination.     

Birth cohort changes in Chinese adolescents' mental health

In China, rapid economic growth and increasing social problems constitute two basic characteristics of contemporary social change. During the process of dramatic social change, an emerging question is how adolescents' mental health has changed across birth cohorts. The present paper reviews four studies of crosstemporal meta-analysis conducted by us. By meta-analysis of previous literature, we examined changes in mean scores on mental health measures over time (from the early 1990s to the mid-2000s). It was found that since the early 1990s, Chinese adolescents' mental health deteriorated across birth cohorts, shown in increased scores on the negative indicators of mental health (e.g. mental problems, anxiety, and depression), whereas self-esteem as a positive trait decreased. The dropping trend in Chinese adolescents' mental health could be attributed to social change, especially increasing social problems. Therefore, adequate attention must be paid to potential influences of social change on individuals' psychological development.