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851.
The first two books on behavior analysis (Skinner, 1938; Keller & Schoenfeld, 1950) had chapter-length coverage of motivation. The next generation of texts also had chapters on the topic, but by the late 1960s it was no longer being given much treatment in the behavior-analytic literature. The present failure to deal with the topic leaves a gap in our understanding of operant functional relations. A partial solution is to reintroduce the concept of the establishing operation, defined as an environmental event, operation, or stimulus condition that affects an organism by momentarily altering (a) the reinforcing effectiveness of other events and (b) the frequency of occurrence of that part of the organism's repertoire relevant to those events as consequences. Discriminative and motivative variables can be distinguished as follows: The former are related to the differential availability of an effective form of reinforcement given a particular type of behavior; the latter are related to the differential reinforcing effectiveness of environmental events. An important distinction can also be made between unconditioned establishing operations (UEOs), such as food deprivation and painful stimulation, and conditioned establishing operations (CEOs) that depend on the learning history of the organism. One type of CEO is a stimulus that has simply been paired with a UEO and as a result may take on some of the motivative properties of that UEO. The warning stimulus in avoidance procedures is another important type of CEO referred to as reflexive because it establishes its own termination as a form of reinforcement and evokes the behavior that has accomplished such termination. Another CEO is closely related to the concept of conditional conditioned reinforcement and is referred to as a transitive CEO, because it establishes some other stimulus as a form of effective reinforcement and evokes the behavior that has produced that other stimulus. The multiple control of human behavior is very common, and is often quite complex. An understanding of unlearned and learned establishing operations can contribute to our ability to identify and control the various components of such multiple determination.  相似文献   
852.
A study of 152 adolescents enrolled in school-based programs for pregnant and parenting youth in Colorado in 1987-88 found no differences in overall stress levels between these two groups; however, salient predictors of stressful life events for pregnant teens were not the same as those for teen mothers. The mean age of study subjects was 16.5 years (range 14-19 years); most were living with a parent rather than the child's father. The dependent variable, level of stress, was measured through use of an abbreviated Life Events Questionnaire. Independent variables were assessed through administration of the Inventory of Social Supportive Behaviors, Rosenberg Self-Esteem Scale, and the Adolescent Coping Orientation for Problem Experiences scale. Of the 5 sources of stress measured (family, accidents, autonomy, deviance, relocation, and distress), only stress related to accidents differed significantly between pregnant and parenting adolescents. For pregnant adolescents, self-esteem was the only significant predictor of the overall level of stress; among parents, the only significant predictor was objective social support. Among adolescents, self-esteem was associated with more frequent use of social support and coping strategies. For parenting adolescents, self-esteem was correlated with the frequency of use of social support, satisfaction resulting from such use, and frequent use of coping strategies. Overall, the independent variables of social support, self-esteem, coping, and age were stronger predictors of stress in pregnant than in parenting adolescent females. This finding suggests that parenting teens may have successfully negotiated the multiple transitions involved in this new stage of the life-cycle. An important implication of this study is the need to design separate counseling components of school-based programs for pregnant versus parenting adolescents rather than to use a single curriculum.  相似文献   
853.
Content-oriented test development requires information derived from a comprehensive job analysis. The job data typically consist of task and skill statements identified by subject matter experts. These statements characterize a target job and are then used to develop the test plan and item budget. The predominant practice for combining data from the task and job skill domains to facilitate preparation of a test plan and item budget is an impressionistic approach. This study reports variations and extensions of an alternative quantitative procedure for linking task and job skill data (Hughes & Prien, 1989) using results obtained in field studies. The results indicate that the procedure reported by Hughes and Prien (1989) yields consistent results. Also, modifications to the procedure result in more detailed solutions.Dr. Charles Lawshe graciously contributed three sets of job analysis data to this research project. Dr. Lawshe also provided a very thoughtful and cogent critique of our attempts to express these thoughts to a user audience and for this we are grateful.  相似文献   
854.
This paper describes a model for group analytic psychotherapy with patients who have been psychotic, namely, schizophrenics and manic depressives. The groups are run on the group centered principles of S. H. Foulkes. They are continuous, slow-open groups, in line with these patients' needs for long-term therapy. A theory is proposed which justifies treating these patients in group-centered groups despite their great dependency needs. The paper also describes the task of the therapist in building and running such a group.Acknowledgments to Geoffrey Elkan, Marcia Levene, Noa Rotem, Aya Levi-Posnanski, Yossi Ezrati, S. Littman, Tamar Sternberg, E. Danilowitz, and C. Kauffman.  相似文献   
855.
The current study tests for the presence of differential order effects in evaluation tasks with consistent and inconsistent evidence as predicted by the Hogarth and Einhorn (1992) belief-adjustment model. The results, based on both between-subjects and within-subjects experiments, demonstrate that there were significant recency effects with inconsistent evidence as predicted, larger recency effects when the inconsistent evidence was farther apart in subjective value as predicted, and significant recency effects even when subjects were given training designed to both help them understand the task as completely as possible and to be better able to assess the pieces of evidence. By including a within-subjects design, we were able to demonstrate that the difference in subjective value between two pieces of evidence is the primary factor influencing the magnitude of the recency effect, regardless of whether the evidence is consistent or inconsistent. This latter finding is unique and contrary to previous research and theory.  相似文献   
856.
Despite the importance of probability assessment methods in behavioral decision theory and decision analysis, little attention has been directed at evaluating their reliability and validity. In fact, no comprehensive study of reliability has been undertaken. Since reliability is a necessary condition for validity, this oversight is significant. The present study was motivated by that oversight. We investigated the reliability of probability measures derived from three response modes: numerical probabilities, pie diagrams, and odds. Unlike previous studies, the experiment was designed to distinguish systematic deviations in probability judgments, such as those due to experience or practice, from random deviations. It was found that subjects assessed probabilities reliably for all three assessment methods regardless of the reliability measures employed. However, a small but statistically significant decrease over time in the magnitudes of assessed probabilities was observed. This effect was linked to a decrease in subjects overconfidence during the course of the experiment.  相似文献   
857.
858.
In contemporary American scholarship, interpretation of Aristotle'sRhetoric has become the locus of sustained and sharp controversy. Differing views of theRhetoric and its significance have become tokens in a more general dispute about what rhetoric is or ought to be. This essay examines three central issues that have emerged in this larger arena of controversy: the relationship between Aristotelian and Platonic conceptions of rhetoric, the relationships among rhetoric, ethics, and epistemology in Aristotle, and the placement of rhetoric within Aristotle's system of arts and sciences.  相似文献   
859.
860.
The arguments against doctors as "double agents" that are presented by Marcia Angell in the preceding article do not defeat the core justification for rationing some relatively high-expense, low-benefit care, and they do not enable us to conclude that clinicians should be barred from any active, substantive role in decisions to limit that care. They do, however, reveal several important conditions that need to govern cost-conscious medial practice in order to preserve an ethic of fidelity to patients: insurers' profits and providers' incomes must be fair, providers must inform patients of any economic reasons that lead to the foregoing of care, and "direct incentive" arrangements must not be used to contain costs.  相似文献   
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