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81.
The operant conditioning of response variability under free-operant and discrete-response procedures was investigated. Two pigeons received food only if their pattern of four pecks on two response keys differed from the patterns emitted on the two immediately preceding trials. Under the free-operant procedure, the keys remained illuminated and operative throughout each trial. There was little variability in the response patterns that resulted, and the pigeons received fewer than one third of the available reinforcers. Under the discrete-response procedure, a brief timeout period followed each response. Variability increased under this procedure, and the pigeons obtained three fourths of the available reinforcers. Previous successes and failures to produce response variability may have been due to the use or failure to use, respectively, a discrete-response procedure. Respondent effects inherent in the free-operant procedure may encourage the development of response stereotypy and, in turn, prevent the development of response variability.  相似文献   
82.
Two persons responded in the same session in separate cubicles, but under a single schedule of reinforcement. Each time reinforcement was programmed, only the first response to occur, that is, the response of only one of the subjects, was reinforced. “Competitive” behavior that developed under these conditions was examined in three experiments. In Experiment 1 subjects responded under fixed-interval (FI) 30-s, 60-s, and 90-s schedules of reinforcement. Under the competition condition, relative to baseline conditions, the response rates were higher and the pattern was “break-and-run.” In Experiment 2, subjects were exposed first to a conventional FI schedule and then to an FI competition schedule. Next, they were trained to respond under either a differential-reinforcement-of-low-rate (DRL) or fixed-ratio (FR) schedule, and finally, the initial FI competition condition was reinstated. In this second exposure to the FI competition procedure, DRL subjects responded at lower rates than were emitted during the initial exposure to that condition and FR subjects responded at higher rates. For all subjects, however, responding gradually returned to the break-and-run pattern that had occurred during the first FI competition condition. Experiment 3 assessed potential variables contributing to the effects of the competitive FI contingencies during Experiments 1 and 2. Subjects were exposed to FI schedules where (a) probability of reinforcement at completion of each fixed interval was varied, or (b) a limited hold was in effect for reinforcement. Only under the limited hold was responding similar to that observed in previous experiments.  相似文献   
83.
The possible role of "effort" in the accuracy of pigeons' performance on a delayed matching-to-sample procedure was investigated by examining the effects of response requirements that accompanied a trial-initiating stimulus and that accompanied a sample stimulus. In the first experiment, the effect of varying the size of a fixed-ratio requirement for responses during an initiating stimulus was compared to that of varying a similar requirement for responses during the sample stimulus. Accuracy increased reliably with increases in the ratio scheduled during the sample stimulus, but was not significantly affected by increases in the ratio scheduled on the key during the initiating stimulus. In another phase of Experiment 1, sample duration was held constant while the ratio requirement was varied during the initiating stimulus. Again, accuracy of matching to sample was not significantly affected by the size of the ratio scheduled during the initiating stimulus. Experiment 2 provided a systematic replication of these results in another group of pigeons and included a more detailed analysis of responding. These results support the view that increases in sample-response requirement facilitate accuracy of delayed matching by increasing the durations of exposure to the sample stimuli, and do not support a role of effort in the sample-response effect. In Experiment 3, the facilitative effect of responses on the sample but not of those on the initiating stimulus was replicated using a simultaneous matching-to-sample procedure. This finding provides further evidence against an interpretation of response-requirement effects that appeals to effort; the finding also suggests that sample exposure might affect initial discrimination of the sample rather than remembering the sample.  相似文献   
84.
A measure of agreement for partially ordered data is suggested that makes use of the k categories with the highest ranks, the ranks of the remaining categories being disregarded. The proposed measure is applied to the Self-Directed Search in order to evaluate its agreement with occupational preference. Other forms of agreement in the Holland classification system can also be assessed by the proposed measure. Examples are congruence and husband-wife and counselor-client agreement.  相似文献   
85.
In the first experiment, subjects rated the similarity of a sample of pairs of random dot patterns generated from 3 prototypes consisting of either 4, 6, or 9 dots. The results of the experiment tended to confirm the structure imposed on the patterns by the construction method. In the second experiment, subjects learned to classify random patterns generated from 2 prototypes with either short or long interprototype distance and consisting of either 4, 6, or 9 dots in a traditional concept identification task. After acquisition, memory for old and new distortions and the prototype, which was not presented during learning, was assessed. The tendency to call a pattern “new” increased with the distance between the pattern and its prototype. In a subsequent transfer test, all subjects saw patterns of either 4, 6, or 9 dots. Performance was above chance and the transfer from larger to smaller patterns tended to be greater than the transfer from smaller to larger patterns. This is consistent with a process of schema formation based on features common to most exemplars of the category. The results are discussed in relation to several theories of concept learning and schema abstraction.  相似文献   
86.
This study examined changes in cognitive-dissonance-related variables during the professional training period. Differences in levels and change in satisfaction with career choice, importance of career, certainty of career decision, self-occupational perceptions, general attitude toward career, time since career decision, and past experience were observed when students who left a collegiate professional training program before program completion were compared with those who remained in the program. Data supports the validity of D. Hershenson and R. Roth's (1966, Journal of Counseling Psychology, 13, 368–370) and V. Harren's (1979, Journal of Vocational Behavior, 14, 119–133) theoretical models of vocational decision and the Assessment of Career Decision Making scale.  相似文献   
87.
Some form of work experience or internship ranks high on the list of criteria used by recruiters of college graduates for positions as management trainees. While internships are discussed positively by students, faculty, and recruiters, their evaluation has been faulted as being highly subjective and lacking in the use of controls and psychometric sophistication. This study used an Institutional Cycle design to investigate changes occurring after participation in internships with three cohorts of college age students. Changes were noted in both terminal and instrumental values and in work-specific needs. In the former, changes moved the profiles of the students closer to those of campus recruiters. In the latter, changes moved the students' needs in the direction of characteristics of the job, away from environmental characteristics.  相似文献   
88.
This study provides a reexamination of the role of different decisional strategies in facilitating progress in occupational decision making. Although the assumptions that a rational decision making style is the preferred mode of vocational functioning has been endorsed in a variety of career theories and interventions, there has been conflicting evidence about the validity of this assumption. To examine the role of different decisional approaches in the progress of making an occupational decision, the rational, intuitive, and dependent decision making style scores of 71 undergraduate students were used to predict progress in occupational decision making. The results of the regression analyses failed to provide support for the assumption that a rational style is the most effective in accomplishing this careerrelated task, but indicated strong support for the conclusion that the use of dependent decisional strategies is damaging, particularly in early stages of the decisional process.  相似文献   
89.
Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings.  相似文献   
90.
Though many studies have examined the predictive power of expressed choices versus that of measured interests, fewer have been concerned with the relationship between the degree to which choices and interests agree and later persistence in an expressed choice. This study explored that relationship, using longitudinal data for 7706 college students and 1372 employed persons. Four levels of congruence between expressed choice and measured interests were identified. Results indicated that persistence in an expressed choice increases systematically as congruence between choice and interests increases. Implications for counselors are noted.  相似文献   
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