A dog's got personality: a cross-species comparative approach to personality judgments in dogs and humans

This research offers a blueprint for how a cross-species comparative approach can be realized empirically. In a single design, parallel procedures and instruments were used in 2 species, dogs (Canis familiaris) and humans (Homo sapiens), to test whether personality differences exist and can be judged in dogs as accurately as in humans. Personality judgments of humans and dogs were compared on 3 accuracy criteria: internal consistency, consensus, and correspondence. Results showed that, on all 3 criteria, judgments of dogs were as accurate as judgments of humans. These findings are consistent with the evolutionary continuity hypothesis and suggest an important conclusion not widely considered by either personality or animal researchers: Personality differences do exist and can be measured in animals other than humans.     

Development and validation of an altruism scale for adults

A new self-report scale, the Altruism Scale for Adults, of 28 items was developed. 14 items were from the Altruism subscale of Wrightsman's Philosophies of Human Nature Scale, and the other 14 items were newly constructed. The scale, anchored by 1: true or 2: false, was administered to 592 Korean men and women in eight subgroups. Cronbach alpha internal consistency was .89, and test-retest reliabilities (n = 52) over 1 and 5 wk. were .90 and .80, respectively. Campbell and Fiske's 1959 multitrait-multimethod analysis showed satisfactory convergent and discriminant validities. Overall results were promising for use of the scale in research and for practical purposes.     

When opportunity knocks: bottom-up priming of goals by means and its effects on self-regulation

Four studies using general attribute goals or specific task goals revealed that attainment means cognitively activate the goals they are perceived to serve. A range of means replicated this effect including goal-directed activities, specific behavioral strategies, or opportunities, assumed to afford effective goal pursuit. The increased accessibility of a currently pursued goal due to "bottom-up" priming by its attainment means improved task persistence and performance, whereas a similarly increased accessibility of a competing goal impeded task persistence and performance.     

Inferring the mental processes of other minds

In 4 experiments, the authors examined how several variables influence the quality and quantity of information that people use to make judgments about other people. The results showed that when possible, participants consistently responded appropriately to variables that influenced information that they used to make inferences about other minds. The results also suggested that under circumstances with no opportunity to contrast behavior in different situations, people might not be sensitive to the quality and quantity of information present. The authors interpreted results to mean that under most circumstances, people make inferences in a way that efficiently uses information about the causes of behavior.     

Effects of mixed versus blocked design on stimulus evaluation: combining underadditive effects

According to the asynchronous discrete coding model of Miller, two manipulations should display underadditive effects on reaction time if they slow down noncontingent stages associated with the processing of two separable dimensions of a stimulus. Underadditive effects are also predicted by a dual route model when a task variable is factorially varied with design type (mixed vs blocked). Interpretations of both underadditive effects and their combination were evaluated. Intact and degraded stimuli were presented to 18 young adults either in a single block (mixed) or in separate blocks (blocked). Spatial stimulus-response (S-R) compatibility was manipulated in all conditions. Stimulus degradation and S-R compatibility interacted underadditively, but only in blocked presentations. Both interpretations of underadditive effects were supported. Eye-movement registrations provided additional support for the alternative routes model.     

Fostering group identification and creativity in diverse groups: the role of individuation and self-verification

A longitudinal study examined the interplay of identity negotiation processes and diversity in small groups of master's of business administration (MBA) students. When perceivers formed relatively positive impressions of other group members, higher diversity predicted more individuation of targets. When perceivers formed relatively neutral impressions of other group members, however, higher diversity predicted less individuation of targets. Individuation at the outset of the semester predicted self-verification effects several weeks later, and self-verification, in turn, predicted group identification and creative task performance. The authors conclude that contrary to self-categorization theory, fostering individuation and self-verification in diverse groups may maximize group identification and productivity.     

Discrimination and the positive-negative asymmetry effect: ideological and normative processes

Research using the minimal group paradigm demonstrates that categorization and ingroup identification can foster intergroup discrimination. However, the positive-negative asymmetry effect shows that less discrimination occurs when negative rather than positive outcomes are distributed. The normative hypothesis explains this asymmetry by the stronger inappropriateness of discrimination in negative than in positive outcome distributions. Results obtained in this minimal group paradigm study (N = 257) did not replicate the asymmetry effect: discrimination occurred in both positive and negative outcome distributions, even if norms against discrimination were stronger in negative than in positive outcome distributions. The absence of the asymmetry effect is explained by the effect of the discrimination-justifying ideology.     

Infant lightness perception: do 4-month-old infants follow Wallach's ratio rule?

When adults view a test disk embedded in a higher-luminance surround, the perceived lightness of the disk is largely determined by the surround-to-disk (S/D) luminance ratio (Wallach's ratio rule). Performance of 4-month-old infants tested with a forced-choice novelty-preference technique was consistent with predictions based on Wallach's ratio rule. This result suggests that the ability to extract and maintain information about local luminance ratios is present early in infancy. This ability is likely to contribute to the development of lightness constancy.     

Contemporary longitudinal methods for the study of trauma and posttraumatic stress disorder

Traditional methods for analyzing trends in longitudinal data have typically emphasized average group change over time. In this article, we propose multilevel, regression-based methods for examining inter-individual differences in intra-individual change and apply these methods to research in trauma and posttraumatic stress disorder (PTSD). The outcome or dependent variable of interest is reconceptualized as an index of dynamic change reflecting the trend or trajectory of an individual's PTSD symptom severity scores across time. A basic statistical model is presented, and analyses and findings are demonstrated with an existing database used in previously published studies. The methods offer promise for future study of the natural course of PTSD chronicity or recovery, risk and resilience factors that influence individual growth or decline, and critical timepoints for intervention.