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971.
Evaluated the hopelessness theory of depression among youth psychiatric inpatients. According to the hopelessness theory of depression, negative attributional style may cross-sectionally relate to an array of psychopathological symptoms. However, in the presence but not the absence of negative life events, negative attributional style relates to the onset and exacerbation of depressive (not other) symptoms. Moreover, negative attributional style relates to depression onset or exacerbation specifically via changes in hopelessness (not other mediators). This study of 60 youth psychiatric inpatients (22 boys and 38 girls; ages 9 to 17, M = 14.33, SD = 1.86), 34 of whom were assessed 2 months after leaving the hospital, tested hopelessness theory. At baseline, participants completed self-report questionnaires on attributional style, hopelessness, self-esteem, depression, and anxiety; at follow-up, questionnaires on negative life events and symptoms were completed. Chart diagnoses were available. Results were consistent with all hypotheses derived from hopelessness theory.  相似文献   
972.
The predictive validity of the Child and Adolescent Functional Assessment Scale (CAFAS) is investigated using the data set generated by the national evaluation of the demonstration service grants funded by the Center for Mental Health Services. Logistic regressions were performed separately for contact with the law and poor school attendance, which were both assessed at 6 months postintake. Other variables included in the model besides the CAFAS total score at intake were age, gender, and family risk factors. The results show that the CAFAS total score at intake was a positive predictor of the likelihood of contact with the law and poor school attendance, even after controlling for age, gender, and risk factors. Furthermore, the CAFAS total score was predictive even after excluding scores on CAFAS subscales, which may have been influenced by absenteeism or delinquency. These findings are consistent with recent research indicating that the CAFAS predicts recidivism in juvenile delinquents.This research was conducted while the author was a Research Associate at the Population Studies Center, University of Michigan, Ann Arbor, MI  相似文献   
973.
974.
975.
Whereas measures of explained variance in a regression and an equation of a recursive structural equation model can be simply summarized by a standard R2 measure, this is not possible in nonrecursive models in which there are reciprocal interdependencies among variables. This article provides a general approach to defining variance explained in latent dependent variables of nonrecursive linear structural equation models. A new method of its estimation, easily implemented in EQS or LISREL and available in EQS 6, is described and illustrated.  相似文献   
976.
Could monaural loudness adaptation be a simple artifact of psychophysical contrast? From adaptation data based on the Ipsilateral Comparison Paradigm (ICP), A. J. Dange, J. S. Warm, E. M. Weiler, and W. N. Dember (1993) concluded that loudness adaptation was not an artifact of psychophysical contrast, but their conclusion was dependent on results from one intensity. This study, involving multiple intensities, re-examined the issue of contrast versus adaptation and generally supported the conclusions of Dange et al. The results also showed an unexpected asymmetry of adaptation based on the direction of the referent modulation used with the ICP technique. Some implications are discussed.  相似文献   
977.
Epidemiological personology refers to a paradigm in which a developmental perspective on individual differences is paired with a population-based sampling frame to yield insights about the role of personality in consequential social outcomes. We review our work in epidemiological personology, linking personality to diverse, problematic social outcomes: Mental disorders, health-risk behaviors, and violence. We conclude that broad-band personality measurement is both feasible and fruitful in large-scale research on problem behaviors, and we call for increased collaboration between personality psychologists and researchers in fields such as public health, epidemiology, and sociology.  相似文献   
978.
Many social scientists appear to possess an overconfidence in the reliability of research results from a single, small-sample, inferential study. In this article, the authors speculate that "user-friendly" statistics packages have the potential to exacerbate statistical misinterpretation by providing researchers with a tool to explore data easily and identify what is interpreted as "reliable" relationships. This article contains an empirical demonstration of the potential problems that arise when a large number of statistical tests are interpreted. Results show that statistically significant results may be unreliable. Also, a zero relationship can erroneously appear as a medium to large effect size relationship when a small sample is used (e.g., n = 30). The authors suggest the need for multiple replications as the criterion of a reliable finding.  相似文献   
979.
Three experiments were conducted to examine pigeons' postponement of signaled extinction periods (timeouts) from a schedule of food reinforcement when such responding neither decreased overall timeout frequency nor increased the overall frequency of food reinforcement. A discrete-trial procedure was used in which a response during the first 5 s of a trial postponed an otherwise immediate 60-s timeout to a later part of that same trial but had no effect on whether the timeout occurred. During time-in periods, responses on a second key produced food according to a random-interval 20-s schedule. In Experiment 1, the response-timeout interval was 45 s under postponement conditions and 0 s under extinction conditions (responses were ineffective in postponing timeouts). The percentage of trials with a response was consistently high when the timeout-postponement contingency was in effect and decreased to low levels when it was discontinued under extinction conditions. In Experiment 2, the response-timeout interval was also 45 s but postponement responses increased the duration of the timeout, which varied from 60 s to 105 s across conditions. Postponement responding was maintained, generally at high levels, at all timeout durations, despite sometimes large decreases in the overall frequency of food reinforcement. In Experiment 3, timeout duration was held constant at 60 s while the response-timeout interval was varied systematically across conditions from 0 s to 45 s. Postponement responding was maintained under all conditions in which the response-timeout interval exceeded 0 s (the timeout interval in the absence of a response). In some conditions of Experiment 3, which were designed to control for the immediacy of food reinforcement and food-correlated (time-in) stimuli, responding postponed timeout but the timeout was delayed whether a response occurred or not. Responding was maintained for 2 of 3 subjects, suggesting that behavior was negatively reinforced by timeout postponement rather than positively reinforced by the more immediate presentation of food or food-correlated (time-in) stimuli.  相似文献   
980.
Urban college student commuters (N = 407) were surveyed about their experiences with stress induced by driving. Of the participants 23.6% reported becoming angry at another driver more than once per day. They rated stress from other drivers as equal to the stress experienced during a college examination but gave slightly lower ratings to traffic congestion, road construction, and finding a parking place as sources of stress. Slow drivers, a child not restrained, and a vehicle following too closely were the highest rated annoying situations. Of participants, 21.6% had reported another driver to the police; nearly 22% said they carried a weapon for protection from other drivers (5.4% said a gun). Men were more than twice as likely as women to carry a weapon and three times as likely to carry a gun. Of the total sample, 19.1% feared being shot by another driver. Most participants (75.8%) said drivers were more aggressive and dangerous than they were five years ago.  相似文献   
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