Reinforcement magnitude and the inhibiting effect of reinforcement

In a two-key concurrent variable-interval schedule (using pigeons), if the reinforcement frequency for one response is held constant while that for the other is increased, the rate of response on the constant key decreases. The immediate reinforcement for key pecking can usually be conceptualized as the change from a condition in which the key light is on and the food hopper light is off to one in which the key light is off and the hopper light is on. The prechange condition is associated with a delay to food of one-half the average interreinforcement interval in effect during this condition. The postchange condition is associated with a delay to food of about .5 seconds. The programming of additional reinforcement results in a decrease in the delay to food associated with the prechange stimulus condition, and thus a decrease in the value of the improvement that results from the change. This would appear to be analogous to a decrease in the amount of reinforcement, and thus sufficient explanation for the decrease in the rate of the response.     

Sensitivity of a linear composite of predictor items to differential item weighting

Many authors have demonstrated for idealized item configurations that equal item weights are often virtually as good for a particular predictive purpose as the item weights that are theoretically optimal. What has not been heretofore clear, however, is what happens to the similarity between weighted and unweighted composites of the same items when the item configuration's variance structure is complex.     

On the base-free measure of change proposed by Tucker,Damarin and Messick

Tucker, Damarin and Messick proposed a base-free measure of change which involves the computation of residual scores that are uncorrelated with true scores on the pretest. The present note discusses this change measure and demonstrates that, because of an incorrect derivation by the authors, properties they attribute to (the coefficient for the regression of true scores from the second testing on true scores from the first testing) are, in fact, properties ofb, the ordinary regression coefficient. A correct derivation of the initial position—change correlation in terms of is obtained, and Tucker et al.'s discussion of the law of initial values is reconsidered.The preparation of this paper was supported by the Learning Research and Development Center supported in part as a research and development center by funds from the National Institute of Education.     

Weakly parallel tests in latent trait theory with some criticisms of classical test theory

A new concept of weakly parallel tests, in contrast to strongly parallel tests in latent trait theory, is proposed. Some criticisms of the fundamental concepts in classical test theory, such as the reliability of a test and the standard error of estimation, are given.     

Two-step weighted least squares factor analysis of dichotomized variables

A two-step weighted least squares estimator for multiple factor analysis of dichotomized variables is discussed. The estimator is based on the first and second order joint probabilities. Asymptotic standard errors and a model test are obtained by applying the Jackknife procedure.     

动机性访谈：一种以咨客为中心的行为改变咨询技术

动机性访谈是目前在西方国家比较流行的一种以咨客为中心的行为改变咨询技术,但在我国关于这一技术的研究和应用都还比较少。本文概述了动机性访谈技术的理论基础、应用原则(表达神入;发展差异;接受阻抗;维持自我效能)和基本技能,并介绍了这一咨询技术的应用现状与研究方向。     

群体绩效和团队效能研究的新进展

近几年来 ,在群体和团队方面的研究比较活跃 ,并取得了不少新的进展。本文在近几年的国内外文献的基础上 ,着重讨论几个与群体绩效有关的长期存在的问题 ,主要包括群体构成、凝聚力、激励、领导、群体目标等因素。同时探讨团队与组织之间的内在联系。然后 ,讨论团队效能研究中的几个开放性问题 ,以及将来研究的新动向新趋势。最后 ,对影响团队效能的几个关键的调节因素作一简要的讨论。     

Longitudinal Gender Differences in Objectified Body Consciousness and Weight-Related Attitudes and Behaviors: Cultural and Developmental Contexts in the Transition from College

Longitudinal analysis of objectified body consciousness, body esteem, self-acceptance, and weight-related attitudes and behaviors in young adults (115 women and 49 men), who were undergraduates in 1993, tested hypotheses developed from theory on the social construction of gendered bodies and the developmental contexts of the post-college transition. Gender differences in body surveillance, body shame, and body esteem and the relationships between these persisted, whereas the relationship between body esteem and self-acceptance decreased for women and was similar to men at Wave 2. For both women and men, body surveillance and body shame decreased and body esteem increased over time, even though BMI also increased. Men wanted to lose weight at levels similar to women at Wave 2 and were equally likely to exercise to control weight, but they were less likely than women to diet. These results fit both cohort and age-related changes models of body experience for women and men.     

Social isolation,aggression, and dominance in attacks in juvenile angelfish,Pterophyllum scalare

The effects of social isolation on aggressive behavior and rank order have been investigated in small groups of juvenile angelfish, Pterophyllum scalare. An experimental protocol including a “double transfer” of the subjects was used, in which fish were transferred to new aquaria in groups, before subsequent isolation and regrouping. A significant decrease in aggression was observed in the first recording session following both isolation and group transfer, after which the level returned to that recorded in the home tanks. The social hierarchy was also perturbed, but changes generally involed the two highest ranking fish in two out of the three groups, and were found not to be statistically significant. The behavior patterns are interpreted as adaptive responses to environmental change. © 1993 Wiley-Liss, Inc.