Social cognitive processes mediating the relationship between exposure to television's sexual content and adolescents' sexual behavior

This study used multiple-group structural equation modeling to test a model explaining the association between exposure to televised sexual content and initiation of intercourse among an ethnically diverse national sample of 1,292 adolescents. The authors hypothesized, on the basis of social-cognitive theory, that exposure to televised sexual content would influence adolescents' safe-sex self-efficacy, sex-related outcome expectancies, and perceived peer norms regarding sex, and that each of these would, in turn, influence intercourse initiation. Findings support a model in which the relationship between exposure to TV's sexual content and intercourse initiation is mediated by safe-sex self-efficacy among African Americans and Whites but not among Hispanics. Outcome expectancies and perceived peer norms may also mediate the link between exposure and intercourse initiation among all 3 racial/ethnic groups, although evidence of this could not be confirmed.     

Exact and resampling probability values for weighted kappa

Permutation procedures to compute exact and resampling probability values for weighted kappa are described. Comparisons with asymptotic probability values demonstrate that exact permutation procedures are advantageous for sparse data sets, whereas resampling permutation procedures are appropriate for both sparse and nonsparse data sets.     

Acquisition and extinction of a simple motor skill as a function of delay of knowledge of results

The present experiment demonstrates that the effects of delay of knowledge of results (KR) in a line drawing task depend upon the dependent variable which is considered and the original response tendency of the subjects. Delay of KR interfered with the acquisition of the correct response when number of correct responses is the dependent variable. When KR was omitted the immediate-KR group continued to make more correct responses than the delayed-KR group. However, there was a significant reduction in correct responses for both groups. When absolute error was the response measure there were no significant differences between immediate-and delayed-KR groups either during acquisition or extinction. Analysis of the type of response made during extinction suggested that the overshooting effect obtained by previous investigators may be typical of short responders trained under conditions of immediate reinforcement but not of those trained under delayed-KR.

Greenspoon and Foreman (1956) obtained clear cut evidence that the effectiveness of knowledge of results (KR) in a line drawing task varies inversely with the time delay between the response and KR. On the other hand, Bilodeau and Bilodeau (1958) were unable to demonstrate a similar effect in five different experiments. Bilodeau and Ryan (1960) hypothesized that the Greenspoon and Foreman findings could not be replicated and they did in fact obtain null results. However, Dyal (1965) has recently replicated the Greenspoon and Foreman results for the case of a 30 sec. delay interval.

The purpose of the present experiment is twofold: (a) to provide replication of Green-spoon and Foreman's study at the 20 sec. delay interval used by Bilodeau and Ryan, and (b) to determine the effect of elimination of KR on a simple motor response which has been formed on the basis of KR.     

Somatovisceral interactions in visceral perception: Abdominal masking of colonic stimuli

Clinical and experimental evidence on referred pain and spinal-afferent convergence demonstrates a close relationship between visceral and somatosensory perception, which is important for current models of symptom perception and central body representation. The study uses a psychophysical approach to quantify these interactions at the perceptual level, taking into account problems of comparable intermodal scaling and the role of awareness. An experiment on somatosensory masking of distension stimuli in the colon is reported in which a multiple staircase method of forced choice discrimination with concurrent sensation ratings was employed. Results showed perceptual masking of visceral by abdominal stimuli but not vice versa. The masking effect was not enhanced by intratomal placement of the abdominal stimulus in the lower left quadrant. This contradicts the spinal sensory convergence model and points to perceptual interactions at higher brain levels. Loglinear analysis of relations between discrimination and subjective sensation revealed qualitative differences of somatovisceral perception at the preconscious as compared to the conscious level. This argues for a two-process model of integrative body perception.     

A template-matching pandemonium recognizes unconstrained handwritten characters with high accuracy

Psychological data suggest that internal representations such as mental images can be used as templates in visual pattern recognition. But computational studies suggest that traditional template matching is insufficient for high-accuracy recognition of real-life patterns such as handwritten characters. Here we explore a model for visual pattern recognition that combines a template-matching and a feature-analysis approach: Character classification is based on weighted evidence from a number of analyzers (demons), each of which computes the degree of match between the input character and a stored template (a copy of a previously presented character). The template-matching pandemonium was trained to recognize totally unconstrained handwritten digits. With a mean of 37 templates per type of digit, the system has attained a recognition rate of 95.3%, which falls short of human performance by only 2%–3%.     

Acculturation Attitudes in Plural Societies

Dans les sociétés culturellement diversifiés, les individus peuvent présenter des attitudes relatives à leurs relations avec les autres et les groupes. Ces attitudes (dites "attitudes d'acculturation") sont liées à des prises de position sur deux problèmes généraux posés à toute personne en acculturation: la préservation culturelle de son propre groupe et le contact avec les autres groupes. On définit les attitudes d'assimilation, d'intégration, de séparation et de marginalisation, puis on les mesure dans plusieurs groupes en acculturation d'Australie et du Canada (les indigènes, les immigrants et les groupes ethniques implantés). On donne la validité et la fidélité des échelles d'attitude, puis on analyse les relations des échelles entre elles par rapport aux deux problèmes sous-jacents que sont la préservation et le contact. Enfin, quelques-unes des applications pratiques des attitudes d'acculturation sont envisagées.     

Mood and sleep in aging women

The possible covariations of mood and sleep was examined in a group of 25 normal, aging women. Mood assessments made in the evenings of 3 consecutive days were independently related to both before and after sleep night. Only two sleep variables: sleep efficiency and latency to first rapid eye movement (REM) period--were reliably related to daytime moods. The relative paucity of relation between mood and sleep variables was interpreted as reflecting a general insulation of sleep from day-to-day mood variations.     

DIRECTORY OF CROSS-CULTURAL PSYCHOLOGICAL RESEARCH

The original Directory, which was published in this Journal (1968, 3, 137–148), has proved to be of value to many psychologists already engaged in, or wishing to begin, cross-cultural research. During the year, a number of persons have written, requesting to be included in an annual supplement, and others have indicated changes of address. This supplement provides the details of both, with a first section listing additions and a second one providing changes of address. Once again, may I invite those wishing to be included in the Directory, to write to me in time for next year's annual supplement ?     

Changing change detection: Improving the reliability of measures of visual short-term memory capacity

The change detection paradigm is a popular way of measuring visual short-term memory capacity. Using the paradigm, researchers have found evidence for a capacity of about four independent visual objects, confirming classic estimates that were based on the number of items that could be reported. Here, we determine the reliability of capacity measures found by change detection. We derive theoretical predictions of the variance of the capacity estimates and show how they depend on the number of items to be remembered and the guessing strategy of the observer. We compare the theoretically derived variance to the variance estimated over repeated blocks of trials with the same observer and find close correspondence between predicted and observed variances. Also, we propose a new version of the two-alternative choice change detection paradigm, in which the choice is unforced. This new paradigm reduces the variance of the capacity estimate substantially.