Testing differences between nested covariance structure models: Power analysis and null hypotheses

For comparing nested covariance structure models, the standard procedure is the likelihood ratio test of the difference in fit, where the null hypothesis is that the models fit identically in the population. A procedure for determining statistical power of this test is presented where effect size is based on a specified difference in overall fit of the models. A modification of the standard null hypothesis of zero difference in fit is proposed allowing for testing an interval hypothesis that the difference in fit between models is small, rather than zero. These developments are combined yielding a procedure for estimating power of a test of a null hypothesis of small difference in fit versus an alternative hypothesis of larger difference.     

Cardiovascular disease prevalence and risk factors of persons with mental retardation

This paper reviews the recent literature on cardiovascular disease (CVD) prevalence, CVD-related mortality, physiological CVD risk factors, and behavioral CVD risk factors in adults with mental retardation (MR). The literature on the potential influences of modifiable behavioral CVD risk factors and the physiological CVD risk factors are also reviewed. Adults with mild to moderate MR residing in community settings appear to have an elevated disease prevalence, elevated CVD-related mortality, more adverse physiological CVD risk factors, and elevated behavioral risk compared to others with and without MR. Preliminary evidence supports the benefits of participating in the recommended physical activity levels and consuming the recommended diets to reduce the risk for CVD. The lack of large-scale longitudinal or experimental research indicates a gap in the research. The development of research-based, appropriate, primary prevention programs and intervention strategies aimed at lowering the risk for CVD is highly recommended. Programs should focus on educating individuals with MR along with direct care providers and family members on the importance of appropriate dietary concepts, physical activity habits, and regular health screenings by physicians. Programs should be individualized to regional and cultural issues.     

Progress in the Molecular-Genetic Study of Intelligence

ABSTRACT— The past decade has seen a major shift in the genetic study of human intelligence; where classic studies aimed to quantify the heritability of intelligence, current studies aim to dissect this heritability into its molecular-genetic components. Five whole-genome linkage scans have been published in the past year, converging on several chromosomal (or genomic) regions important to intelligence. A handful of candidate genes, some of which lie in these genomic regions, have shown significant association to intelligence and the associations have been replicated in independent samples. Finding genes brings us closer to an understanding of the neurophysiological basis of human cognition. Furthermore, when genes are no longer latent factors in our models but can actually be measured, it becomes feasible to identify those environmental factors that interact and correlate with genetic makeup. This will supplant the long nature–nurture debate with actual understanding.     

AN EMPIRICAL ANALYSIS OF MEASUREMENT EQUIVALENCE WITH THE INDCOL MEASURE OF INDIVIDUALISM AND COLLECTIVISM: IMPLICATIONS FOR VALID CROSS-CULTURAL INFERENCE

The INDCOL measure of individualism and collectivism ( Singelis et al., 1995 ) has been used increasingly to test complex cross-cultural hypotheses. However, sample differences in translation, culture, organization, and response context might threaten the validity of cross-cultural inferences. We systematically explored the robustness of the INDCOL, for various statistical uses, in the face of those 4 threats. An analysis of measurement equivalence using multigroup mean and covariance structure analysis compared samples of INDCOL data from the United States, Singapore, and Korea. The INDCOL was robust with regard to the interpretability of correlations, whereas differences in culture and translation pose an important potential threat to the interpretability of mean-level analyses. Recommendations regarding the interpretation of the INDCOL and issues in the analysis of measurement equivalence in cross-cultural research are discussed.     

Norme de motivation intrinsèque et utilité sociale : recherches dans le champ organisationnel

Numerous theoretical models have been proposed to explain motivation in organizational settings. Several authors such as Herzberg, Deci and Ryan distinguish between intrinsic and extrinsic motivation. A new approach to intrinsic motivation (François, 2003) is now developping in France. It consists of considering that “intrinsic motivation” is a social norm. We have tested the normativity of intrinsic motivation in two field studies using the judge's paradigm. The first study was conducted on 52 recruiters, the second was conducted on 25 experts evaluating a project concerning the creation of an organization. Results show that evaluators prefered intrinsically motivated than extrinsically motivated candidates in both studies. Finally evaluators used utilitarians traits to describe intrinsically motivated candidates. This result gives force to a normative interpretation of intrinsic motivation.     

Recurrence plot analyses suggest a novel reference system involved in newborn spontaneous movements

The movements of newborns have been thoroughly studied in terms of reflexes, muscle synergies, leg coordination, and target-directed arm/hand movements. Since these approaches have concentrated mainly on separate accomplishments, there has remained a clear need for more integrated investigations. Here, we report an inquiry in which we explicitly concentrated on taking such a perspective and, additionally, were guided by the methodological concept of home base behavior, which Ilan Golani developed for studies of exploratory behavior in animals. Methods from nonlinear dynamics, such as symbolic dynamics and recurrence plot analyses of kinematic data received from audiovisual newborn recordings, yielded new insights into the spatial and temporal organization of limb movements. In the framework of home base behavior, our approach uncovered a novel reference system of spontaneous newborn movements.     

Cultural differences in neural function associated with object processing

Behavioral research suggests that Westerners focus more on objects, whereas East Asians attend more to relationships and contexts. We evaluated the neural basis for these cultural differences in an event-related fMRI study. East Asian and American participants incidentally encoded pictures of (1) a target object alone, (2) a background scene with no discernable target object, and (3) a distinct target object against a meaningful background. Americans, relative to East Asians, activated more regions implicated in object processing, including bilateral middle temporal gyrus, left superior parietal/angular gyrus, and right superior temporal/supramarginal gyrus. In contrast to the cultural differences in object-processing areas, few differences emerged in background-processing regions. These results suggest that cultural experiences subtly direct neural activity, particularly for focal objects, at an early stage of scene encoding.     

What Do Women Want? A New View of Women’s Sexual Problems

Recent attempts to medicalize women’s sexual “dysfunction” are critiqued and a “New View” of women’s sexual problems is introduced. The author argues for a female-centered perspective on women’s sexual desires and problems, based on a review of the literature on women’s sexuality and her observations of young women’s sexual experiences from 25 years of teaching Human Sexuality to undergraduate women. The review suggests that a pill or a patch cannot adequately address the sexual problems commonly experienced by US women.