Fungible Weights in Multiple Regression

Every set of alternate weights (i.e., nonleast squares weights) in a multiple regression analysis with three or more predictors is associated with an infinite class of weights. All members of a given class can be deemed fungiblebecause they yield identical SSE (sum of squared errors) and R ² values. Equations for generating fungible weights are reviewed and an example is given that illustrates how fungible weights can be profitably used to evaluate parameter sensitivity in multiple regression. The author wishes to thank Drs. Robyn Dawes, William Grove, Markus Keel, Leslie Yonce, Joe Rausch, the editor, and three anonymous reviewers for helpful comments on earlier versions of this article.     

Structural brain abnormalities in psychopaths-a review

The biological basis of psychopathy has not yet been fully elucidated. Few studies deal with structural neuroimaging in psychopaths. The aim of this article is to review these studies in order to contribute to our understanding of the biological basis of psychopathy. Data in the literature report a reduction in prefrontal gray matter volume, gray matter loss in the right superior temporal gyrus, amygdala volume loss, a decrease in posterior hippocampal volume, an exaggerated structural hippocampal asymmetry, and an increase in callosal white matter volume in psychopathic individuals. These findings suggest that psychopathy is associated with brain abnormalities in a prefrontal-temporo-limbic circuit-i.e. regions that are involved, among others, in emotional and learning processes. Additionally, data indicate that psychopathic individuals cannot be seen as a homogeneous group. The associations between structural changes and psychopathic characteristics do not enable causal conclusions to be drawn, but point rather to the important role of biological brain abnormalities in psychopathy. To gain a comprehensive understanding of this, psychopathy must be viewed as a multifactorial process involving neurobiological, genetic, epidemiological and sociobiographical factors.     

Stereotypes and Shifting Standards: Some Paradoxical Effects of Cognitive Load

Four studies tested a prediction derived from the shifting-standards model (Biernat, Manis, & Nelson, 1991) regarding the role stereotypes play in judgments of individual group members. Previous research has documented that stereotyping effects are stronger on objective than on subjective response scales, and the present studies found that these effects were intensified when participants were under heavy cognitive load. Stereotyping effects increased on objective judgment scales, but decreased on subjective scales. The latter is a paradoxical effect: By relying on stereotypes, one may increasingly use them as within-category comparative standards, which leads to the apparent reduction of stereotyping effects.     

Towards tolerance: Representations of superordinate categories and perceived ingroup prototypicality

According to Mummendey and Wenzel (1999), group members tend to perceive their ingroup, relative to an outgroup, as more prototypical of the superordinate category encompassing both groups. Hence, they tend to regard the outgroup as deviating from the norms of the superordinate category. Factors that inhibit perception of relative ingroup prototypicality should thus promote intergroup tolerance. In two experiments, the representation of the superordinate category was manipulated. Both an undefinable prototype (Experiment 1; N=63) and a complex representation (Experiment 2; N=88) led to a decrease in relative ingroup prototypicality. Dual identification with the ingroup and the superordinate category increased relative ingroup prototypicality, which was negatively correlated with positive attitudes towards the outgroup. The findings supported Mummendey and Wenzel’s assumptions about the conditions that lead to intergroup tolerance.     

Psychology's contributions to understanding and addressing global climate change

Global climate change poses one of the greatest challenges facing humanity in this century. This article, which introduces the American Psychologist special issue on global climate change, follows from the report of the American Psychological Association Task Force on the Interface Between Psychology and Global Climate Change. In this article, we place psychological dimensions of climate change within the broader context of human dimensions of climate change by addressing (a) human causes of, consequences of, and responses (adaptation and mitigation) to climate change and (b) the links between these aspects of climate change and cognitive, affective, motivational, interpersonal, and organizational responses and processes. Characteristics of psychology that cross content domains and that make the field well suited for providing an understanding of climate change and addressing its challenges are highlighted. We also consider ethical imperatives for psychologists' involvement and provide suggestions for ways to increase psychologists' contribution to the science of climate change.     

When and how politicians' disrespect affects voters' trust in the political system: The roles of social judgments and category prototypicality

We propose that one politician's disrespectful behavior can spill over to voters' generalized judgments of politicians and thereby affect trust in the political system. We delineate the spillover effect along the basic dimensions of social judgment, communion, and agency. Moreover, we argue that any spillover effect is contingent on the focal politicians' category prototypicality, that is, their representativeness of politicians as such. Conducting an experiment (N = 392) and a field study (N = 273), we found that politicians' respect only affected trust through generalized communion ratings. This spillover only occurred if the observed politician was perceived as prototypical. Our findings provide new insights on when and how individual politicians may be able to undermine voters' trust in the political system.