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991.
Three rats, lever pressing for food delivered on a fixed-interval 128-s schedule, were presented with a 16-s opportunity to drink from a retractable water source. The temporal placement of the water probe within the reinforcement cycle was varied sequentially, in steps of 16 s. Although the lever-pressing pattern was modulated by the intercalated water probe, water consumption during the probe itself was a decreasing function of time from the following reinforcer. These results were interpreted as evidence against the notion that schedule-induced drinking is a "ubiquitous" phenomenon and are congruent with results from other "intruded stimulus" experiments.  相似文献   
992.
Seven undergraduates participated in a concurrent-choice experiment with monetary reinforcers. Response-independent analogues of variable-interval and variable-ratio schedules were used to assess whether subjects would maximize reinforcement rate. The optimal pattern of behavior, in terms of maximizing reinforcement rate, involved a large bias toward the ratio alternative, with only occasional sampling of the interval schedule. Most experiments with pigeons, however, demonstrate matching of response rates to reinforcement rates, with only slight biases for the ratio schedule. Although subjects in the present experiment allocated more time to the ratio alternative than required by matching, the magnitude of the bias did not approximate that predicted by a maximizing account. After exposure to clock stimuli correlated with the operation of each schedule, 1 subject's behavior did show a substantial level of bias, increasing the total number of reinforcers obtained, and lay at a point between the predictions of matching and maximizing. The other subjects, however, continued to respond less optimally. The present results can be accounted for by a view of matching that incorporates the effects of delayed reinforcement.  相似文献   
993.
Four empirical studies of the roles of self-report questionnaires, tests, and ratings in employment interviews, staff appraisal, and personnel validation surveys are presented in order to examine the number and relationships of psychological constructs derived from data provided by candidates, employees, and their assessors. Test results are related to different kinds of criteria, including job offers following interview, supervisor ratings on the job, and objective indices of work performance. From the practices reported and observed in these various contexts, a theory of personal appraisal mechanisms in occupational settings is derived using data reduction and linear regression methods. Applications of cognitive information processing theory to self-reports and ratings by individuals, and of exchange theory to the social context of panel discussions among assessors, provide a key to understanding why psychometric measures of personal qualities vary in their power to predict work performance in spite of consistent construct validity.  相似文献   
994.
Previous research indicates that vasopressin-containing (LE) rats are capable of adapting to the stress of food restriction, whereas vasopressin-deficient (DI) rats cannot adapt to this stressor. It has been postulated that abnormalities in glucose metabolism may be one of the factors leading to the demise of food-restricted DI rats. The present study was conducted to determine if taste preferences are altered in DI animals and if the presentation of exogenous glucose, in the form of sucrose solutions, can ameliorate the effects of the stress of food restriction. Four different concentrations of sucrose solutions were presented to LE and DI rats under the food-restricted condition. In both strains, an 8% sucrose solution was preferred over 0%, 16%, and 32% concentrations, with DI rats consuming more of this concentration than LE rats. Thus, when DI rats had the opportunity of maintaining glucose homeostasis by exogenous supplements, they maintained body weight, displayed no stomach pathology, and survived.  相似文献   
995.
    
In contrast to previous research on apologies, which has examined their role in enhancing impressions of those issuing them (e.g., Darby and Schlenker, 1989), the research reported here draws upon Goffman’s (1955) analysis of the “corrective cycle” and is concerned with constraints associated with the receipt of apologies. Study 1 examines the implications for the actor of accepting, not accepting, or rejecting apologies. It is demonstrated that across a variety of judgments, most positive views of the actor result when apologies are accepted; least positive views are associated with their rejection. A follow-up study sought to establish whether this effect would occur under circumstances in which unconvincing apologies are rejected. Results indicate that the apology’s status (convincing versus unconvincing) has no bearing on perceptions of actors. Based on a hypothetical role-play format, Study 2 addresses the matter of whether actors experience a subjective sense of constraint upon receipt of unsatisfactory apologies. The data suggest that there exists a pronounced tendency to accept such apologies, though typically with conditions that would be specified to the offender. More general implications of the data are discussed.  相似文献   
996.
This study presents two experiments that demonstrate that the memory trace of a tobe-remembered item develops along a dimension (continuum) from coarse/general to fine/specific. Similarly, forgetting is shown to be a reverse movement along this dimension from fine to coarse, as increasingly less fine attributes are lost. The attribute acquisition pattern of this Progressively Finer Attributes Theory is robust and predictable, valid for experimentally unstructured (Experiment 2) as well as experimentally structured (Experiment 1) material.  相似文献   
997.
This paper explores some of the ways in which the environment functions with respect to behavior within an explanatory framework analogous to that of evolutionary biology. In both the behavioral and organic domains, the environment functions differently with respect to individual occurrences and evolutionary units. Within the behavioral domain, the problem of accounting for an occurrence of an operant instance differs from that of accounting for the existence of the operant unit of which the instance is a part. Maintaining these distinctions in levels of analysis within the behavioral domain, we focus first on operant units and operant instances as products of evolutionary processes occurring in the behavioral domain and second upon the causal role of the environment with respect to the existence of operant units and the occurrence of operant instances. The environment's function is selective with respect to origin, maintenance, suppression, and extinction of behavioral populations. At the level of operant instances, the environment has instantiating functions-evocative or alterative. Evocative functions are exemplified by discriminative relations, and alterative functions include both conditional and motivative relations. Implications are considered regarding extension of the analogy to more complex behavior-environment relations.  相似文献   
998.
Compliance with postpartum visits after teenage births in the US was examined among 289 Hispanic teenagers, of whom 127 were born in Mexico or border towns, who delivered at Harris County Hospital District and scheduled postpartum appointments at the Teen Health Clinic. The mean age was 17.31 years for mothers and 21.95 years for fathers. 56.7% (164) were married. 49.8% lived with husbands, 25.8% with parents, 22.3% with friends/relatives, and 2.1% alone. 74.7% stated that they had no social supports. 88.9% had a term delivery, 8.3% a preterm delivery, and 2.8% a fetal loss. 67.5% were first births, 5.5% had a previous abortion, and 3.1% had a previous miscarriage. 23.2% had a previous child, and 0.7% had a previous preterm delivery. Some form of prenatal care was received by 85.1%. 34.3% reported no further educational plans. 17.3% (50) returned for a scheduled postpartum visit. Mothers with a prior history of a premature birth or miscarriage were more likely to return postpartum compared to mothers with a first or prior birth. The differences are marginally significant. None of the mothers with a prior abortion returned. 34.9% of the returning teen mothers were more likely to have had prenatal care. Returning mothers also were a larger percentage of those with no future educational plans. 13.4% of returning mothers had an available social support system. Country of origin was not associated with support systems, prenatal care, return status, educational plans, pregnancy history, or current birth outcome. Out of the 50 returning, 20 were Mexican-born and married. Only Mexican marital status was found to be a significant variable explaining differences. Marital status had no effect on the 26 US native-born returnees. 92% of the Mexican-born teens were married and had a support system. The most dramatic feature of this study is the high level of noncompliance among both US-born and Mexican-born adolescents. There were few distinguishing features between these two groups. Return status was affected by very few features and was achieved by a very small percentage of the study population. The suggestion is made that poverty, a lack of health insurance, and poor knowledge of English, as representative of cultural dissimilarity, may be responsible for poor use of preventive care.  相似文献   
999.
The authors review four new instruments designed to assess multicultural counseling competence in trainees and practicing professionals. The Cross-Cultural Counseling Inventory—Revised (CCCI-R), the Multicultural Counseling Awareness Scale—Form B (MCAS:B), the Multicultural Counseling Inventory (MCI), and the Multicultural Awareness-Knowledge-and Skills Survey (MAKSS) were each critically reviewed in terms of item development, psychometric properties, and pragmatic utility. Specific research suggestions for continued empirical validation on the instruments are posited, and strong cautions regarding their current use in training are leveled.  相似文献   
1000.
The authors discuss the role of an academic department in promoting faculty development. Specifically, the authors (a) define faculty development from a departmental perspective, (b) discuss stages and seasons in academic careers, and (c) delineate specific faculty development goals and programs within the department.  相似文献   
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