Desires in Practical Reasoning

Inferences from desired ends to intended necessary means seem to be among the most unproblematic elements of practical reasoning. A closer look dissolves this appearance, however, when we see that such inferences are defeasible. We can nevertheless understand such inferences as leading to the adoption of plans, by analogy with inferences leading to explanations. Plans should satisfy at least some important ends desired by the agent, be consistent with the satisfaction of other desired ends, and be inconsistent with as few desired ends as possible. A rational plan may rule out the satisfaction of some desires, however, and this feature explains the defeasibility of such inferences.     

Psychoticism as a dimension of personality: a multivariate genetic test of Eysenck and Eysenck's psychoticism construct

In this study, we applied multivariate genetic analysis, a generalization of factor analysis and behavior genetic analysis, to responses to items of the Psychoticism scale of the Eysenck Personality Questionnaire by 2,903 adult same-sex Australian twin pairs. Item loadings on genetic, shared environmental, and nonshared environmental common and specific factors were estimated. The genetic factor structure differed considerably from the environmental structures, particularly in men. The genetic correlation between suspiciousness items and items reflecting unconventional or tough-minded attitudes or hostility to others was negative, but the environmental correlation was positive. Thus, conventional behavior genetic studies that have reported significant heritability of psychoticism, on the basis of analyses of scale scores, are misleading as to what trait is being inherited.     

A sequential theory of psychological discrimination

A theory of discrimination which assumes that subjects compare psychological values evoked by a stimulus to a subjective referent is proposed. Momentary differences between psychological values for the stimulus and the referent are accumulated over time until one or the other of two response thresholds is first exceeded. The theory is analyzed as a random walk bounded between two absorbing barriers. A general solution to response conditioned expected response times is computed and the important role played by the moment generating function (mgf) for increments to the random walk is examined. From considerations of the mgf it is shown that unlike other random walk models [Stone, 1960; Laming, 1968] the present theory does not imply that response conditioned mean correct and error times must be equal. For two fixed stimuli and a fixed referent it is shown that by controlling values of response thresholds, subjects can produce Receiver Operating Characteristics similar or identical to those predicted by Signal Detection Theory, High Threshold Theory, or Low Threshold Theory.     

GENETIC AND ENVIRONMENTAL CONTRIBUTIONS TO VARIANCE IN AGE AT FIRST SEXUAL INTERCOURSE

Abstract— Little is known about the relative importance of genetic and environmental factors as determinants of age at first sexual intercourse. In this study, subjects were 5,080 individuals from the Australian Twin Registry (3,310 females, 1,770 males, age range 27–70 years, median 40 years) who completed a semistructured interview by telephone in 1992–1993. Self-reported age at first intercourse correlated higher for identical (monozygotic) twins than for nonidentical (dizygotic) twins. Structural equation model fitting found that the genetic contribution to variance was considerably greater among twins aged 40 years or less (72% for males and 49% for females) than for those aged from 41 to 70 years (0% for males and 32% for females). Among the older cohort, there was evidence that somewhat different aspects of the shared social environment influenced age at onset in males and females. In a more laissez-faire social climate in recent decades, it is likely that biological and psychological characteristics that are partly under genetic control significantly influence the age at which a person commences sexual activity.     

Who drives divergence? Identity signaling, outgroup dissimilarity, and the abandonment of cultural tastes

People often diverge from members of other social groups: They select cultural tastes (e.g., possessions, attitudes, or behaviors) that distinguish them from outsiders and abandon tastes when outsiders adopt them. But while divergence is pervasive, most research on the propagation of culture is based on conformity. Consequently, it is less useful in explaining why people might abandon tastes when others adopt them. The 7 studies described in this article showed that people diverge to avoid signaling undesired identities. A field study, for example, found that undergraduates stopped wearing a particular wristband when members of the "geeky" academically focused dormitory next door started wearing them. Consistent with an identity-signaling perspective, the studies further showed that people often diverge from dissimilar outgroups to avoid the costs of misidentification. Implications for social influence, identity signaling, and the popularity and diffusion of culture are discussed.     

A Test of Contextual Theory: The Relationship Among Relational Ethics,Marital Satisfaction,Health Problems,and Depression

Few studies have examined the theoretical underpinning of contextual theory. Using structural equation modeling, the relationship among relational ethics (recognized as the most important aspect of contextual theory), marital satisfaction, depression, and illness was examined. Data came from a national sample of 632 mid-life, married individuals. Results supported Nagy’s contextual theory. The total score of the Relational Ethics Scale was a significant predictor of marital satisfaction, and marital satisfaction was significantly associated with depression and health problems. Vertical and horizontal subscales of relational ethics also were significant predictors of depression and health problems through the mediating variable of marital satisfaction.     

The Role of Harsh Discipline in Explaining Sex Differences in Conduct Disorder: a Study of Opposite-Sex Twin Pairs

In the current study, two hypotheses about the role of harsh discipline (HD) in explaining the sex difference in the prevalence of conduct disorder (CD) were evaluated: that boys exhibit more CD than girls because (1) they are exposed to more HD and/or (2) there is a greater association between HD and CD in boys. These hypotheses were evaluated in a sample of male and female adult twins from different families (N = 3,502) as well as a sample of adult twin brothers and sisters (N = 655) in order to examine the extent to which sex differences remained after controlling for between-family differences. Retrospective reports of HD experienced between ages 6–13 and DSM-IV CD symptoms experienced before age 18 were obtained via structured psychiatric telephone interviews. Boys reported higher mean levels of HD and CD than girls, both between and within families, and the results of model-fitting analyses suggested that differences in the use of harsh disciplinary practices for sons versus daughters may partially explain the sex difference in the prevalence of CD. Between families, the relation between HD and CD was greater for girls than boys, but within families, there was no evidence of a sex difference in the relation between HD and CD. Inconsistent between-family and within-family results suggest that factors that differ between families are confounded with sex differences in the relation between HD and CD. A more stringent test of sex differences involves eliminating these between-family differences by studying boys and girls within the same family.     

The repetition-break plot structure: a cognitive influence on selection in the marketplace of ideas

Using research into learning from sequences of examples, we generate predictions about what cultural products become widely distributed in the social marketplace of ideas. We investigate what we term the Repetition-Break plot structure: the use of repetition among obviously similar items to establish a pattern, and then a final contrasting item that breaks with the pattern to generate surprise. Two corpus studies show that this structure arises in about a third of folktales and story jokes. An experiment shows that jokes with this structure are more interesting than those without the initial repetition. Thus, we document evidence for how a cognitive factor influences the cultural products that are selected in the marketplace of ideas.