Negation: A theory of its meaning,representation, and use

This article presents a model-based theory of what negation means, how it is mentally represented, and how it is understood. The theory postulates that negation takes a single argument that refers to a set of possibilities and returns the complement of that set. Individuals therefore tend to assign a small scope to negation in order to minimize the number of models of possibilities that they have to consider. Individuals untrained in logic do not know the possibilities corresponding to the negation of compound assertions formed with if, or, and and, and have to infer the possibilities one by one. It follows that negations are easier to understand, and to formulate, when individuals already have in mind the possibilities to be negated. The paper shows that the evidence, including the results of recent studies, corroborates the theory.     

Grounding Bayesian accounts of numerosity and variability effects in a similarity-based framework: the case of self-organising maps

ABSTRACT

In this paper, we propose self-organising maps as possible candidates to explain the psychological mechanisms underlying category generalisation. Self-organising maps are psychologically and biologically plausible neural network models that can learn after limited exposure to positive category examples, without any need of contrastive information. They reproduce human behaviour in category generalisation, in particular, the Numerosity and Variability effects, which are usually explained with Bayesian tools. Where category generalisation is concerned, self-organising maps deserve attention to bridge the gap between the computational level of analysis in Marr's hierarchy (where Bayesian models are often situated) and the algorithmic level of analysis in which plausible mechanisms are described.     

The role of body image in the prevention of eating disorders

This article reviews theory and research pertaining to prevention of negative body image and eating disorders. Research derived from the social cognitive model (SCM) and non-specific vulnerability-stressor (NSVS) model indicates that sustained prevention effects for attitudes and behaviors are possible, but not easy to achieve or explain. These limitations are considered in the context of promising research derived from a third model, critical social perspectives (CSP). We conclude that (1) research on practice should aim beyond the examination of efficacy in order to clarify the active ingredients contributing to prevention; and (2) research informed by each of the divergent perspectives can be used to enrich theory and practice in the field of eating disorders prevention.     

Heterogeneous factor analysis models: A bayesian approach

Multilevel factor analysis models are widely used in the social sciences to account for heterogeneity in mean structures. In this paper we extend previous work on multilevel models to account for general forms of heterogeneity in confirmatory factor analysis models. We specify various models of mean and covariance heterogeneity in confirmatory factor analysis and develop Markov Chain Monte Carlo (MCMC) procedures to perform Bayesian inference, model checking, and model comparison.We test our methodology using synthetic data and data from a consumption emotion study. The results from synthetic data show that our Bayesian model perform well in recovering the true parameters and selecting the appropriate model. More importantly, the results clearly illustrate the consequences of ignoring heterogeneity. Specifically, we find that ignoring heterogeneity can lead to sign reversals of the factor covariances, inflation of factor variances and underappreciation of uncertainty in parameter estimates. The results from the emotion study show that subjects vary both in means and covariances. Thus traditional psychometric methods cannot fully capture the heterogeneity in our data.     

Agonistic behavior and growth in newly emerged brown trout (Salmo trutta L) of sea‐ranched and wild origin

Selection experiments and game theory models have revealed that the changes in agonistic behavior following selection for rapid growth rate of fish depend on the access of food. If food is spatially restricted and in excess of demand, the intensity of agonistic behaviors will decrease. This prediction was tested in an experiment on wild and sea‐ranched brown trout (Salmo trutta L.) fry originating from a common stock. Agonistic behavior, activity, and specific growth rate were studied in tanks (56 × 56 cm) at high (159.4 fry/m²) and low (9.6 fry/m²) stocking densities given either a large or small food ration (3.0% and 1.5%, respectively, food per total body weight and day). Observations were done during 4 days in each trial. Generally, fry of sea‐ranched origin had a higher growth rate. No differences in activity were found. Intensity of agonistic behavior was higher among wild groups. There was a tendency for interaction between density and strain, e.g., wild fish were relatively more aggressive at higher densities. Food ration had no effect on level of agonistic behavior. These results indicate that the selection for rapid growth in hatcheries may indirectly select for reduced aggressiveness. Genetic integrity and diversity of wild populations may be threatened when interbreeding occurs between wild and hatchery fish. Aggr. Behav. 28:145–153, 2002. © 2002 Wiley‐Liss, Inc.     

A Latent Variable Framework for Power Estimation Within Intervention Contexts

This paper presents a latent growth SEM approach for the estimation of treatment effects, and power to detect such effects, within a true experimental design setting in which subjects are randomly assigned to treatment and control conditions. Power estimation is a critical component of intervention experiment design and the testing of their results. Although researchers have become increasingly sophisticated in applying tests for statistical significance in intervention contexts, few are aware of the power of these tests. The issues raised in this paper are not new; however, reminding researchers to consider these points is important. Exactly how the researcher handles these issues will depend on the questions asked and the resources available, as well as other considerations. Discussion underscores the relationship between the reliability of a study's measures and concomitant increases in power obtained within the SEM framework.     

基于概念复杂度的加工容量观

探讨了一个认知科学的概念——容量,主要是介绍一种基于概念维度的加工容量观.这种观点认为加工容量最好以进入某一特定运算过程的独立维度来定义,容量的增长意味着可以表征更多的维度,而概念的组块与分割是常用的表征策略.个体差异通过表征的清晰度和有效性的差异来表现,而认知的发展则是成熟与经验相互作用的结果.     

Spiritual Development Across the Adult Life Course: Findings from a Longitudinal Study

Longitudinal data spanning early (30s) and older (late 60s/mid-70s) adulthood were used to study spiritual development across the adult life course in a sample of men and women belonging to a younger (born 1928/29) and an older (born 1920/21) age cohort. All participants, irrespective of gender and cohort, increased significantly in spirituality between late middle (mid-50s/early 60s) and older adulthood. Members of the younger cohort increased in spirituality throughout the adult life cycle. In the second half of adulthood, women increased more rapidly in spirituality than men. Spiritual involvement in older age was predicted by religious involvement and personality characteristics in early adulthood and subsequent experiences of negative life events.