Design controversies and the generation effect: Support for an item-order hypothesis

We performed three experiments to investigate an earlier finding of Nairne, Riegler, and Serra (1991) that item generation disrupts the long-term retention of serial order. Experiment 1 demonstrated a clear advantage of reading over generating on a reconstruction test when reading and generating occurred in pure, but not mixed, lists. Experiment 2 showed that the standard generate advantage is seen in free recall of mixed, but not pure, lists, even when recall is immediately followed by reconstruction of serial order of the same items. Experiment 3 replicated Experiment 1, but with the use of an incidental learning procedure. The results of all three experiments are consistent with the claim that generation has dissociative effects on item and order memory; moreover, these dissociative effects help to explain design controversies-in the -generation effect literature.     

Decision rules for selecting effect sizes in meta-analysis: a review and reanalysis of psychotherapy outcome studies

This study deals with some of the judgmental factors involved in selecting effect sizes from within the studies that enter a meta-analysis. Particular attention is paid to the conceptual redundancy rule that Smith, Glass, and Miller (1980) used in their study of the effectiveness of psychotherapy for deciding which effect sizes should and should not be counted in determining an overall effect size. Data from a random sample of 25 studies from Smith et al.'s (1980) population of psychotherapy outcome studies were first recoded and then reanalyzed meta-analytically. Using the conceptual redundancy rule, three coders independently coded effect sizes and identified more than twice as many of them per study as did Smith et al. Moreover, the treatment effect estimates associated with this larger sample of effects ranged between .30 and .50, about half the size claimed by Smith et al. Analyses of other rules for selecting effect sizes showed that average effect estimates also varied with these rules. Such results indicate that the average effect estimates derived from meta-analyses may depend heavily on judgmental factors that enter into how effect sizes are selected within each of the individual studies considered relevant to a meta-analysis.     

The relationship between sex role identity and marital adjustment

One hundred forty-four maritally distressed clinic couples and 138 nonclinic couples participated in a study investigating the relationship between individual sex role identity and marital adjustment. Subjects completed Baucom's (1976) masculinity (MSC) and femininity (FMN) scales, and either the Dyadic Adjustment Scale (DAS; Spanier, 1976) or the Marital Adjustment Scale (MAS; Locke & Wallace, 1959). As predicted, femininity was related to positive marital adjustment; masculinity was related as well, but perhaps to a lesser degree. Androgyny within a relationship was found to be highly desirable, whereas marriages involving undifferentiated individuals were more likely to be distressed.     

Dopaminergic polymorphisms and educational achievement: results from a longitudinal sample of Americans

Although educational attainment has been found to be moderately heritable, research has yet to explore candidate genes for it. Drawing on data from the National Longitudinal Study of Adolescent Health, in the current study, we examined the association between polymorphisms in three dopaminergic genes (DAT1, DRD2, and DRD4), a dopamine index, and educational attainment. Statistically significant effects were found for DAT1, DRD2, DRD4, and the dopamine index for highest level of education. This study is the first to our knowledge that links measured genes to educational attainment.     

Adolescent substance use groups: antecedent and concurrent personality differences in a longitudinal study

This study attempted to extend Shedler and Block's (1990) influential study, which found that adolescent drug experimenters had the healthiest personality functioning compared to abstainers and frequent users. Using a prospective design, we examined the relationship between antecedent and concurrent personality and age-18 substance use in a community sample of 1,298 twins (96% Caucasian, 49% male). Personality measures at ages 11 and 18 assessed positive emotionality (agentic and communal), negative emotionality, and constraint. Substance use groups-abstainers, experimenters, and problem users-were created at age 18. Age-18 substance use groups differed in age-11 and age-18 constraint such that problem users were lower than experimenters, who were lower than abstainers. Age-18 substance use groups did not differ in age-18 positive emotionality. However, abstainers were significantly lower than experimenters in communal positive emotionality, whereas female abstainers scored higher in agentic positive emotionality than female experimenters, who scored higher than female problem users. Experimenters were significantly lower in negative emotionality than problem users. Our findings are inconsistent with the notion that experimenters had the healthiest personality functioning and instead suggest different strengths and weaknesses for each group. Future studies should examine agentic and communal positive emotionality separately.     

Different groups, different motives: identity motives underlying changes in identification with novel groups

Social identification is known to have wide-reaching implications, but theorists disagree about the underlying motives. Integrating motivated identity construction theory with recent social identity research, the authors predicted which motives underlie identification with two types of groups: interpersonal networks and social categories. In a five-wave longitudinal study of social identity processes among 268 new university residents, multilevel analyses showed that motives involved in identity enactment processes--self-esteem, belonging, and efficacy--significantly predicted within-person changes in identification with flatmates (an interpersonal network group), whereas motives involved in identity definition processes--meaning, self-esteem, and distinctiveness--significantly predicted within-person changes in identification with halls of residence (an abstract social category). This article discusses implications for research into identity motives and social identity.     

Delineating Selection and Mediation Effects Among Childhood Personality and Environmental Risk Factors in the Development of Adolescent Substance Abuse

Utilizing the large, longitudinal Minnesota Twin Family Study (N?=?2510; 96 % European American ancestry), we examined the influence of several person-environment transactions on adolescent substance abuse. We focused on the two childhood personality traits found to be most predictive of substance abuse in this sample—socialization (willingness to follow rules and endorse conventional values) and boldness (social engagement and assurance, stress resilience, thrill seeking)—and the environmental variables of antisocial and prosocial peers, academic engagement, parent–child relationship quality, and stressful life events. Path analysis revealed that low socialization had a selection effect for each environmental risk factor, that is, socialization at age 11 predicted environmental risk at age 14, after controlling for the stability of the environmental variables from ages 11 to 14. Antisocial peers and academic engagement at age 14 then mediated some of the risk of low socialization on substance abuse at age 17, but the majority of risk for substance abuse was accounted for by the stability of socialization from age 11 to 14. Boldness at age 11 also increased risk for substance abuse, but did so primarily via a direct effect. The findings help to parse the nature of person-environment transactions across multiple personality traits and contextual risk factors that contribute to adolescent substance abuse.