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231.
Three studies examined the role of the perceived typicalness of an out-group member on her effectiveness in improving evaluations of her group. Subjects were students at two adjacent colleges. In the first study they interacted with a member of the out-group college. The interaction was either pleasant or unpleasant, and the contact person either confirmed or disconfirmed several stereotypes of the out-group (typicalness manipulation). Subjects evaluated the out-group most favorably when they interacted with the typical-pleasant member of the out-group. The second study demonstrated that contact with a highly typical member is not beneficial if her typicalness is based on stereotypes that reflect negatively on the subject's in-group. Several explanations of the typicalness findings were considered in a third study. Support was found for the hypothesis that the more typical member is perceived to be more predictive of the personality and actions of other out-group members.  相似文献   
232.
The effects of a graduated prompting treatment procedure were analyzed in three phases of an experiment on the training and generalization of reaching-grasp responding in 2- to 4-year-old blind, severely or profoundly retarded children. In Phase 1, we used a multiple-baseline across-subjects design to investigate the effectiveness of the treatment on midline reach-grasp responding. In Phase 2, we used a reversal design to investigate the effects of repeated implementations and withdrawals of the treatment. In both phases, generalization to right and left positions was measured. In Phase 3, in a multiple-baseline across-responses design, the treatment was implemented in right and left positions. Also in Phase 3, shift of stimulus control from toy-sound to verbal instructions was measured. The results showed that (a) the graduated prompting procedure was effective in training reach-grasp responding in all three children; (b) for one child, the effects were durable over repeated applications of the treatment procedure, but were not maintained during withdrawals; (c) for another child, the treatment procedure was effective in teaching reach-grasp responding in all three positions; and (d) for the same child, training of reach-grasp responding generalized to toys presented without sound, given only the verbal instruction.  相似文献   
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Two experiments assessed infant sensitivity to figural coherence in point-light displays moving as if attached to the major joints of a walking person. Experiment 1 tested whether 3- and 5-month-old infants could discriminate between upright and inverted versions of the walker in both moving and static displays. Using an infant-control habituation paradigm, it was found that both ages discriminated the moving but not the static displays. Experiment 2 was designed to clarify whether or not structural invariants were extracted from these displays. The results revealed that (1) moving point-light displays with equivalent motions but different topographic relations were discriminated while (2) static versions were not, and (3) arrays that varied in the amount of motion present in different portions of the display were also not discriminated. These results are interpreted as indicating that young infants are sensitive to figural coherence in displays of biomechanical motion.  相似文献   
236.
Correlations were computed between United States per capita consumption of cigarettes and 41 different foods for the years 1964–1977 and 1968–1973. There were significant negative correlations between consumption of cigarettes and sugar. Few other foods showed any relationship to cigarette consumption. These findings corroborate the results of a recent human laboratory study of cigarette smoking and food consumption and a recent animal study of the effects of nicotine on food consumption, taste preferences, and body weight. Taken together, these studies suggest that the inverse relationship between cigarette smoking and body weight may be partially explained by changes in consumption of sweet-tasting high caloric foods.  相似文献   
237.
Nursery schoolers and first- and third-graders participated in an interview which assessed recall, comprehension, and perceived importance of three sources of self-knowledge: social feedback, self-observation, and social comparison. For recall measures, these sources were embedded in stories about a child making a self-discovery. Recall of all three sources improved with grade level, and feedback was the best remembered self-validational process. Comprehension was defined as the ability to identify the sources as depicted in line drawings, and it, too, increased with grade level. All three sources were well understood by older children, but preschoolers had difficulty with the concept of social comparison. Ratings of importance, also assessed using line drawings, were independent of grade level. When selecting their own “very best” source of self-knowledge, children cited self-observation most frequently. A supplementary sample of preschoolers nominated the best source of self-knowledge for other children rather than for themselves; under these instructions, feedback from others emerged as the preferred source.  相似文献   
238.
Complaints of anxiety, often meetingDiagnostic and Statistical Manual of Mental Disorders, 3rd ed. (DSM-III), criteria for anxiety disorder, are among the most common problems presenting to health practitioners. In spite of the frequency of anxiety and anxiety disorders, little is known about the basic psychopathology of these conditions that would lead to the development of more efficient and effective treatments and possible preventive efforts. Recently, there has been an increase in research on the psychopathology of anxiety disorders from biological, psychological, and social perspectives. The National Institute of Mental Health's Clinical Research Branch sponsored a 2-day workshop of investigators representing diverse research approaches to discuss emerging issues and research practices within the anxiety disorders. Discussions centered on a review of the general areas of classification, phenomenology, and etiology. A selective summary of this workshop is presented along with recommendations for specific research directions.  相似文献   
239.
One purpose of this investigation was to examine the importance of assessing treatment integrity in a study evaluating a treatment for specific anxiety disorders. Three subjects, two social phobics and one simple phobic, received self-instruction training (Phase I) followed by exposure and self-instruction training (Phase II) in a multiple baseline across subjects design. All subjects were assessed during a pretreatment baseline and throughout treatment using measures of treatment integrity and measures of change in phobic severity. Improvement took place at different times for different subjects. Measures of treatment integrity, which consisted of monitoring of self-statements as well as practice outside the session, indicated that treatment was not always received as intended and that improvement was correlated with practice. The usefulness of measures of treatment integrity in both clinical and research settings is highlighted.  相似文献   
240.
The most widely-used computer programs for structural equation models analysis are the LISREL series of Jöreskog and Sörbom. The only types of constraints which may be made directly are fixing parameters at a constant value and constraining parameters to be equal. Rindskopf (1983) showed how these simple properties could be used to represent models with more complicated constraints, namely inequality constraints on unique variances. In this paper, two new concepts are introduced which enable a much wider variety of constraints to be made. The concepts, phantom and imaginary latent variables, allow fairly general equality and inequality constraints on factor loadings and structural model coefficients.During the preparation of this article, it was discovered that another researcher, Jack McArdle, had concurrently and independently discovered some of the techniques reported here. While he has chosen not to publish his research, I wish to acknowledge his work. I would like to thank Art Woodward for telling me about sort-of simple structure.  相似文献   
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