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261.
A computational processing behavior-dynamic model was instantiated in the form of a computer program that "behaved" on the task developed by Nevin (1969). In this classic discrete-trials experiment, the relative frequency of choosing a response alternative matched the relative frequency of reinforcement for that alternative, the local structure of responding was opposite that predicted by momentary maximizing (i.e., the probability of a changeover decreased with run length), and absolute and relative response rates varied independently. The behavior-dynamic model developed here qualitatively reproduced these three results (but not in quantitative and specific detail) and also generated some interesting, as-yet-untested predictions about performance in Nevin's task. The model was discussed as an example of a stochastic behavior-dynamic alternative to algebraic behavior theory.  相似文献   
262.
ALCOVE: an exemplar-based connectionist model of category learning.   总被引:16,自引:0,他引:16  
ALCOVE (attention learning covering map) is a connectionist model of category learning that incorporates an exemplar-based representation (Medin & Schaffer, 1978; Nosofsky, 1986) with error-driven learning (Gluck & Bower, 1988; Rumelhart, Hinton, & Williams, 1986). Alcove selectively attends to relevant stimulus dimensions, is sensitive to correlated dimensions, can account for a form of base-rate neglect, does not suffer catastrophic forgetting, and can exhibit 3-stage (U-shaped) learning of high-frequency exceptions to rules, whereas such effects are not easily accounted for by models using other combinations of representation and learning method.  相似文献   
263.
The Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; DSM-III-R) operationally defines disorder essentially as "statistically unexpectable distress or disability." This definition is an attempt to operationalize 2 basic principles: that a disorder is harmful and that a disorder is a dysfunction (i.e., an inability of some internal mechanism to perform its natural function). However, the definition fails to capture the idea of "dysfunction" and so fails to validly distinguish disorders from nondisorders, leading to invalidities in many of DSM-III-R's specific diagnostic criteria. These problems with validity are traced to DSM-III-R's strategies for increasing reliability.  相似文献   
264.
The purposes of this study were to assess the career development needs of entering medical students as measured by the Medical Career Development Inventory and to examine gender differences in responses to the inventory. A total of 115 entering medical students (representing two entering classes) took the inventory two months prior to matriculation. Analysis suggested that this sample of entering students had formed a vocational identity and that they had evaluated the suitability and viability of a commitment to a physician's career. However, the participants had not formed a clear picture of their specialty interest and goals. No significant gender differences were indicated. A recommended career assistance workshop is presented as appropriate for these students' needs.  相似文献   
265.
Less is known about the effects of primary relationships on psychological health for homosexual men and women than for heterosexual men and women. Given the HIV/AIDS epidemic, the primary relationships of homosexual men are especially important to examine at the present time. Using questionnaire data collected from 259 homosexual men, this study examined the effects of status and quality of relationship on psychological health. Analysis indicated that homosexual men who are in primary relationships experience fewer depressive symptoms and greater well-being than other homosexual men but that being in a relationship does not predict changes in these outcomes over time. Men who report high quality of relationship show improvements over time in psychological health. These findings are discussed in light of the HIV/AIDS epidemic.  相似文献   
266.
This study compared two different interpretation styles (tentative and absolute), two levels of subjects' reactance (high and low), and gender on the counselor's social influence, willingness to see the counselor, willingness to help, ability to help, and subjects' anger. No significant main effects or interaction were found for the counselor's social influence, but men in contrast to women perceived the counselor as more willing to help and indicated that they were more willing to see the portrayed counselor. Highly reactant subjects were more willing to see the counselor when absolute interpretations were used; they also thought the counselor was more willing to help when absolute interpretations were used, whereas low reactant subjects thought the counselor was more willing to help when tentative interpretations were used. Mixed results were found for subjects' anger.  相似文献   
267.
This article examined the relationship between impulsiveness and attitudes toward institutional authority among Australian secondary school students. Reliable questionnaire measures of these constructs were completed by 48 boys and 57 girls, about 14 years of age. Correlations between impulsiveness and attitude to authority differed between the sexes, with a significant negative correlation of -.43 being obtained for boys only.  相似文献   
268.
Analyses of responses from a clinical sample of 120 patients (primarily schizophrenics) and from 158 college students to the Cognitive Slippage Scale, a scale designed by Miers and Raulin to identify speech deficits and confused thinking in schizophrenic and schizotypal personality disorders showed high internal reliability; Cronbach's coefficients alpha were .89 and .86 in the clinical and college student samples, respectively. The mean scale scores significantly differentiated the two samples. Also, change scores over 4 wk. showed adequate stability for both samples. Item analysis indicated Items 11, 20, 21, and 28 may not reliably discriminate between schizophrenic and college student samples. Over-all, these preliminary results are consistent with the reliability and validity of the scale.  相似文献   
269.
It has become increasingly accepted that pain is not simply a sensation generated by nociceptors, but a perceptual phenomenon with particular emotional qualities. The purpose of this article is to bring together vastly different streams of research on the divisibility of pain into sensory and affective components. Empirical evidence for this divisibility is drawn from recent studies using multivariate statistics, signal detection theory, and unidimensional scaling. An important conclusion is that separable though pain components may be, they are not necessarily independent. In critiquing previous research, new criteria are derived for partitioning pain into sensory and affective components. Finally, speculations are offered as to how these same components might be synthesized on the basis of theories of perceptual organization.  相似文献   
270.
Recent evidence suggests that there is a relationship between depression and immunity. On the basis of these studies, it has been argued that depressed mood may increase susceptibility to disease by means of aberrations occurring within the immune system. Empirical research investigating the relationship between depression and immunity is reviewed here. Studies examining both clinical and nonclinical manifestations of depression are discussed and evaluated. This review reveals that indexes of immunocompetence are lower among people exhibiting depressive symptomology and suggests that immune alterations may be more related to dysphoric mood than to specific situations or events. Alternative hypotheses accounting for links between depressed affect and altered immune states are provided, and suggestions for future research are offered.  相似文献   
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