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941.
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   
942.
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   
943.
944.

The effects of varying decision outcome dispersion on organizational decision making were investigated under individual and group decision making conditions. Thirty-six female and pg]36 male subjects made decisions for organizational decision scenarios in which outcomes affected primarily the decision maker, people other than the decision maker, or a group of which the decision maker was a member. Subjects rated their levels of perceived risk and confidence in their decisions and made decisions within a simulated context of either a small or a large organization. Results indicated that subjects perceived significantly less risk and more confidence in their decisions when outcomes affected primarily themselves rather than others regardless of whether the decisions were made individually or by a group. Males perceived their decisions as significantly more risky than females. Induced organizational size did not significantly influence decision making.

  相似文献   
945.
The influence of a videotape, shown in a hospital admitting room, on patients' state anxiety and concerns about hospitalization was assessed in a preliminary study. For both state anxiety and specific concerns regarding hospitalization the pretest scores on each variable accounted for the preponderance of the variance in the posttest scores. In both instances, the intervention and the interaction of the intervention with the pretest scores accounted for less than 1% of variance in the outcome. While finding small effects to be significant for such a small sample (N = 93) is unlikely, the sample size was adequate to detect medium to large effects. More important was the fact that 73.33% of the videotape intervention group indicated that they did not watch the video, which leads us to the conclusion that this intervention as tested is not worthwhile.  相似文献   
946.
104 women, between the ages of 18 and 45 years, were surveyed to investigate the relationship between premenstrual symptomatology, as measured by the Modified Menstrual Distress Questionnaire, and irrational thinking, as measured by the General Attitude and Belief Scale. The women who reported greater premenstrual symptomatology also reported significantly higher scores in the "need for comfort" irrationality subscale. This indicated that these women had particular difficulty dealing with hassles and the resulting feelings of tension and irritability in the premenstruum. It was suggested that the absence of significant effects for other rationality-irrationality subscales could be associated with testing at different times during the menstrual cycle. Irrationality, like other conditions (such as anxiety and depression) prevalent in the premenstruum, could change in intensity across phases of the menstrual cycle.  相似文献   
947.
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   
948.
106 high school students from a small rural high school completed the Children of Alcoholics Scale, Zaks and Walters' Aggression Scale, Beck Depression Scale, and a modified version of the Beck Scale of Suicide Ideation. Analyses of variance showed boys were not experiencing suicide ideation any more than girls; suicide ideation was similar across the four grades, but on aggression alcohol-dependent boys scored significantly higher than girls, and in Grade 9 boys' scores were significantly higher than those in Grade 10. The sophomores' scores on alcohol dependency were significantly lower than the freshmen's scores. Boys and children from divorced homes had higher scores on aggression than girls and children from nondivorced homes. Children from homes in which alcohol was used had higher depression scores than children from nonalcoholic homes. Freshman girls and sophomore boys had higher depression scores than senior boys and girls. A Pearson r of 0.28 between scores on alcohol dependency and suicide ideation was significant, but research is needed to understand better the associations of thoughts of suicide and drug-alcohol dependency among these high school students so strategies for prevention and intervention can be focused.  相似文献   
949.
The scores of 15 adolescents who had a primary diagnosis of Posttraumatic Stress Disorder, 21 of Conduct Disorder, and 23 control subjects on the Beck and Reynolds depression scales were correlated .58 over-all, .73 for the Posttraumatic group, .48 for the Conduct Disordered group, but .37 for controls. The Reynolds scale did not identify depression in these adolescents as effectively as did the Beck scale.  相似文献   
950.
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