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171.
The effects of reinforcement schedules on rats' choice behavior in extinction were studied. In a free-operant chamber equipped with two retractable bars, the experimental animals were trained to press the bars separately for a food reward. One bar delivered the reward on a continuous reinforcement (CRF) schedule, and the other delivered the reward on a partial reinforcement (PRF) schedule. Control animals earned the reward from both bars with the same reinforcement schedule, either a CRF or a PRF. When both bars were simultaneously available during extinction, the experimental animals responded more frequently to the CRF than to the PRF alternative, demonstrating a reversed within-subjects partial reinforcement extinction effect (PREE). A conventional between-subjects PREE was replicated in the control subjects. The results of this study were inconsistent with both Amsel's (1962, 1967) frustration hypothesis and Capaldi's (1966, 1967) sequential hypotheses.  相似文献   
172.
We examined the validity of need scales of the Edwards Personal Preference Schedule (EPPS) by correlating them with a measure of the five basic factors of personality; we also considered test format as a possible source of invalidity. Three hundred thirty (223 women, 107 men) undergraduate students completed both the NEO Personality Inventory (NEO-PI)--a measure of the five factors--and one of two versions of the EPPS. Results show that both ipsative and normative versions of the EPPS could be meaningfully interpreted within the five-factor model, although the ipsative, forced-choice format of the standard EPPS apparently lowered validity coefficients and decreased convergent and discriminant validity. We argue that the five-factor model can provide a useful interpretive context for evaluating many clinical measures.  相似文献   
173.
174.
In a court clinic sample of 107 child sexual and nonsexual offenders, Minnesota Multiphasic Personality Inventory (MMPI) profiles did not differ as a function of arrests for sexual versus nonsexual offending. However, a three-group cluster-analytic solution was generated. Two of these clusters replicated those derived by Hall, Graham, and Shepherd (1991). The first cluster was unelevated, with Scales 4 and 9 as high points. The second cluster had MMPI Scales 4, 8, 2, and 7 as the highest scales. The third cluster was even more elevated than the other two clusters, characterized by extreme elevations on MMPI Scales F, 2, 4, 6, 7, and 8. The somewhat different results of this study versus previous studies (e.g., Hall et al., 1991) may be a function of the different populations sampled. The results provide evidence of within-group heterogeneity among sexual and nonsexual offenders that may be as important as between-group differences.  相似文献   
175.
There is usually a long period of time between infection with the AIDS virus and manifestation of symptoms. Asymptomatic patients often would benefit from elective surgery for diseases such as arthritis which are unrelated to their infection. The surgeons' decisions to accept the risks to themselves, their spouses, and their operating teams in order to relieve pain and suffering appear to be based upon two covenants; one concerns their role within the doctor-patient relationship, and the other concerns their relationship to what they see as the ultimate meaning in life.  相似文献   
176.
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   
177.
A capacity theory of comprehension: individual differences in working memory.   总被引:77,自引:0,他引:77  
A theory of the way working memory capacity constrains comprehension is proposed. The theory proposes that both processing and storage are mediated by activation and that the total amount of activation available in working memory varies among individuals. Individual differences in working memory capacity for language can account for qualitative and quantitative differences among college-age adults in several aspects of language comprehension. One aspect is syntactic modularity: The larger capacity of some individuals permits interaction among syntactic and pragmatic information, so that their syntactic processes are not informationally encapsulated. Another aspect is syntactic ambiguity: The larger capacity of some individuals permits them to maintain multiple interpretations. The theory is instantiated as a production system model in which the amount of activation available to the model affects how it adapts to the transient computational and storage demands that occur in comprehension.  相似文献   
178.

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.

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179.
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   
180.
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   
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