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931.
932.
933.
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
934.
Weiler EM Sandman DE Janson-Pinto J Dange AJ Dember WN Warm JS Nelson WT 《The Journal of general psychology》2000,127(4):365-371
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
935.
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
936.
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
937.
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
938.
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
939.
Attitudes about antidepressants: influence of information about weight-related side effects 总被引:2,自引:0,他引:2
Antidepressant drugs are frequently prescribed for women and have various side effects, including potential effects on body weight. This experiment examined the effects of information about the weight-related side effects of antidepressants on women's attitudes toward the drugs. 60 college women were randomly assigned to read about one of two drugs, fluoxetine (Prozac) or imipramine (Tofranil). Participants were either told or not told about veridical weight-related side effects, namely, weight loss for Prozac and weight gain for Tofranil. As hypothesized, weight-gain information lowered the personal acceptability of Tofranil, and weight-loss information enhanced the acceptability of Prozac. Although research with clinical populations is required, undergraduate women's decisions about the use of antidepressant medications may be influenced by societal body-image ideals. 相似文献
940.
Rosenblum S Katz N Hahn-Markowitz J Mazor-Karsenty T Parush S 《Perceptual and motor skills》2000,90(2):587-594
The purpose of this study was to examine environmental influences on perceptual and motor skills of children from immigrant Ethiopian families in Israel in comparison with those of Israeli-born children. The subjects were divided into groups based on age (6- to 8-yr.-olds and 10- to 12-yr.-olds) and length of time in Israel. The results of this study show that the perceptual and motor performance of 6- to 8-yr.-old, less recent Ethiopian immigrants is similar to that of the recent Ethiopian immigrants of the same age. A difference exists between those two groups and the Israeli-born children of the same age. In the 10- to 12-yr.-old age group, there is a marked difference between the performance of the two groups of Ethiopian immigrants. The difference between the less recent immigrants and the Israeli-born children is smaller for most tasks; however, the less recent immigrants' performance is still poorer than that of the Israeli children. These results are compatible with those of other studies describing the difficulties encountered by children who had not studied in formal educational settings and those who have had that experience. 相似文献