Visual discrimination of spectral distributions

Human observers seem to be able to use different features that classify materials with a large degree of accuracy. In this paper, we look at human perception of statistical properties of the spectral distribution in a scene. We investigated whether human observers can discriminate just as accurately between coloured textures that have a spectral distribution due either to shading only or to both shading and specular reflectance as between uniform colours. Thresholds for the discrimination of coloured textures are about 15 times as high as thresholds for the discrimination of uniform colours, provided there is a sharp transition between the two colours. However, the coloured texture thresholds are only 1.5 times higher when we introduce a gradual transition between the two colours. There are also distinct qualitative differences in discrimination thresholds for different base colours. These differences cannot be predicted from discrimination thresholds for uniform colours. Human observers are surprisingly good at discriminating between a material edge and a shadow edge in complex scenes. Statistical differences in the orientation of the colour distributions in colour space might be used to accomplish this. In a second experiment we investigated how well observers can discriminate between two linear distributions in colour space that have the same base colour but different orientations. When we vary the line-length in R, G, B space, thresholds cannot be predicted completely by the conservation of the average distance between the two distributions. This means that observers use not only the maximum colour difference in the stimulus to do the task, but other cues are also involved.     

Incremental validity in the psychological assessment of children and adolescents

Incremental validity in the process of psychological assessment of children and adolescents is explored. The authors highlight the dependence of the incremental validity of assessment information on factors such as goal of assessment, other information available, base rate of the problem or outcome, age or gender of the child, and type of problem being assessed. The authors discuss the incremental validity of assessment information from alternate sources, methods, and constructs. In view of the limited number of studies directly relevant to incremental validity in child clinical assessments, the authors call for more clinically relevant research. To have the greatest impact on child and adolescent services, this research must be readily generalized and immediately relevant to actual clinical practice.     

Universal sex differences in the desire for sexual variety: tests from 52 nations, 6 continents,and 13 islands

Evolutionary psychologists have hypothesized that men and women possess both long-term and short-term mating strategies, with men's short-term strategy differentially rooted in the desire for sexual variety. In this article, findings from a cross-cultural survey of 16,288 people across 10 major world regions (including North America, South America, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, South/Southeast Asia, and East Asia) demonstrate that sex differences in the desire for sexual variety are culturally universal throughout these world regions. Sex differences were evident regardless of whether mean, median, distributional, or categorical indexes of sexual differentiation were evaluated. Sex differences were evident regardless of the measures used to evaluate them. Among contemporary theories of human mating, pluralistic approaches that hypothesize sex differences in the evolved design of short-term mating provide the most compelling account of these robust empirical findings.     

Effects of initial success or failure in a stressful or relaxed environment on subsequent task performance

Forty male and 40 female undergraduate subjects worked on anagram problems in either a stressful or a relaxed environment after having experienced either success or failure on a similar task. Internal arousal, which was expected to be minimal following success in a relaxed setting and maximal following failure in the stressful environment, was assumed to bear an inverted U-shaped relation to performance. Consistent with the implications of these assumptions, achievement in a stressful setting was lower following initial failure than following initial success, while initial failure in a relaxed environment facilitated subsequent performance. The interpretation of these results was supported by the effects of the experimental variables on indirect measures of arousal as well as by the relationship between direct measures of arousal and task performance. In addition, the achievement of female subjects tended to be facilitated by failure while the performance of males was consistently debilitated by it.     

“Nature and Society Give Women a Great Habit of Suffering”: Germaine de Staël's Feminism and Its Challenges

Germaine de Staël (1766–1817), despite having published a considerable body of work, is seldom regarded as a feminist philosopher. Unlike, for instance, Mary Wollstonecraft of the same period, Staël is not directly arguing for the equality of the sexes. She even, at times, makes surprisingly derogatory remarks about women's nature. I argue that she is nevertheless putting forward a brand of difference feminism, which deserves our attention as a contribution to feminist reflections on gender norms in the early modern era. Staël's contribution takes the form of a plea for the improvement of women's lives that engages with the combined action of nature and society. I clarify the meaning that we should ascribe to Staël's frequent appeals to nature and argue that, for her, society and education should be used to correct (alleged) natural weaknesses instead of reinforcing them. I also give an overview of Staël's political proposals toward the improvement of women's lives, which call for a better form of political regime than the one she lived in, as well as a better access to education and a more egalitarian conception of marriage.     

Perceived mattering in stepfamilies: A social relations model analysis

The current study examined the respective role of stepfamily members' individual characteristics and their dyadic relationships in stepfamily members' perceptions of mattering to one another. Parents, stepparents, and adolescents from 86 stepfamilies participated. Applying social relations model analyses, several trends emerged regarding the relative importance of individual and dyadic factors. Parents' and adolescents' reports of mattering to one another were mainly driven by individual factors, whereas relational factors were important to understand the reports of mattering in which the stepparent was one of the dyad members. These findings contribute to stepfamily research by highlighting that stepfamily members' sense of belonging is at least partly a function of the interpersonal adaptation between the stepparent and other family members.