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81.
This paper reports an experiment testing two hypotheses. The first is that the value or utility associated with a payment to one's self and a payment to a co-worker can be represented as an additive function of a utility for own payment (nonsocial utility) and a utility for the difference between own and other's payment (social utility). The second hypothesis is that changes in the amount of work accomplished by one's self and/or the other should influence the social, but not the the nonsocial utilities. Support for both hypotheses is reported.  相似文献   
82.
This experimental study examined the effects on syllogistic reasoning in grades 6 and 12 of certain contextual narrative variables. The experimental task consisted of 27 varied syllogistic problems based on information contained in three narrative texts—a fantasy passage, a realistic passage, and a contractual passage. Versions of these texts were constructed for each group reading level. Analysis of the data revealed several significant interactions between subject groups and treatment variables. In particular, younger subjects performed better than grade 12 subjects on problems following the fantasy narrative, while the older subjects did better with the other two passages. The results suggest that some orthodox views about concrete-versus formal-operational reasoning abilities and about the distinction between abstract and concrete materials need to be reassessed within a discourse-processing framework that is sensitive to the discourse worlds in which problems are embedded.The author wishes to acknowledge the support of an Isaak Walton Killam Doctoral Scholarship for this research.  相似文献   
83.
Educably mentally retarded (EMR) students and nonhandicapped students from their mainstream classes completed semantic differential ratings of a stereotypic popular teen-ager, juvenile delinquent, and special education student. Subjects also rated their global self-concepts and situation-specific self-concepts within the mainstream and the special class settings. Ratings were done at the beginning (Time 1) and the end (Time 2) of a semester. Results showed that mainstream classes did not "de-label" EMR students. Within the mainstream class, the number of EMR students who saw themselves as similar to a special education student significantly increased over time. Moreover, at Time 2, EMR students were more likely to think of themselves as similar to a special education student in their mainstream class than in their special education class. However, EMR subjects' global self-concepts did not change. Implications for mainstreaming are discussed.  相似文献   
84.
Recent evidence suggests that people are sensitive to the degree of contingency between their actions and ensuing outcomes, but little is known about the way in which such contingency judgments develop as more and more information about the contingency is provided. Three experiments examined this issue in the context of a video game. In Experiment 1, it was found that contingency judgments follow growth functions: When the contingency was positive, judgments increased toward a positive asymptote, and when the contingency was negative, judgments decreased toward a negative asymptote. When the contingency was zero, judgments themselves remained close to zero but were biased by the overall frequency with which the outcome occurred. In Experiment 2, it was shown that the growth function was not the result of the anchoring of early judgments at the zero point. The bias in judgments when the contingency is zero was investigated in Experiment 3. The results are discussed in terms of rule-based analyses and contemporary theories of conditioning.  相似文献   
85.
For four of six autistic children who underwent intensive behavioral treatment, the nature of their self-stimulatory behavior changed from initial lowlevel motor behaviors (such as rocking, spinning, twirling) to differing kinds of higher-level behaviors (such as lining of objects, echolalic speech, and preoccupation with spelling and numerical values). The children who changed to the highest levels of self-stimulatory behavior also showed the largest gains in treatment (as determined by IQ scores, school placement, etc.). The changes in self-stimulatory behaviors were attributed to the intense teaching of appropriate social behaviors and the explicit therapeutic suppression of low-level, self-stimulatory behaviors. The long-term therapeutic effects of changing from lower-to higher-level forms of self-stimulatory behavior were discussed.This study was supported by a grant from the National Institute of Mental Health (grant MH 11440). We want to express our thanks to the parents who allowed us to study their children. We gratefully acknowledge the assistance of Maria Audero with the design of the weighted measure, and Tracee Parker with the collection of the data.  相似文献   
86.
This study examined the effects of academic stress upon components of Type A behavior and cardiovascular reactivity. In a longitudinal design, heart rate and blood pressure responses to the Type A Structured Interview (SI) and additional laboratory challenges were measured in medical students at three points during an academic semester. Sessions 1 and 3 were scheduled during vacation periods; Session 2 took place during an intensive examination week. Results indicated that three “stylistic” components of Pattern A derived from the SI—loud and explosive speech, short response latency, and potential for hostility—increased significantly during the exam period. Similar increases achieved marginal significance for another stylistic component, rapid and accelerated speech. By contrast, global Type A assessments did not increase with academic demands. Cardiovascular reactivity was significantly but only moderately stable across the three sessions, showing less consistency than has been reported in previous research. In addition, there was little evidence in this study that cardiovascular reactivity was potentiated by academic stress or by Type A behavior. These results demonstrate the influence of naturalistic environmental factors on overt behavioral components that have recently been suggested as coronary risk factors. Therefore, it is advisable for future experimental and epidemiological research to examine the social and environmental context in which these behaviors occur.  相似文献   
87.
The acquired immune deficiency syndrome (AIDS) has rapidly become the most serious medical consequence of injecting illicit drugs. Its potential impact on intravenous (IV) drug use is enormous. Human immunodeficiency virus (HIV, also known as HTLV-III and LAV), the virus that causes AIDS, appears, usually, to lead to lifelong infection. At present there is no effective treatment, and the treatments under development may require lifelong antiviral therapy. Since most of the antibody produced in response to HIV infection does not neutralize the virus, and since there is substantial genetic variation in the virus, it will be difficult to develop a vaccine. Even after vaccines are developed, testing their safety and efficacy will be formidable problems. Until either effective treatment or vaccines are developed, control of the epidemic among IV drug users must be attempted through behavior change/prevention efforts. In this paper we will review the epidemiology of AIDS among IV drug users and characteristics of the IV drug-use subculture relevant to prevention efforts. We will then identify different target groups for these prevention efforts, present available evidence about behavior change in these groups, and then briefly discuss how to prevent transmission of HIV to heterosexual partners who are not themselves IV drug users and to the children of IV drug users.  相似文献   
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