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991.
The present study was designed to explore both the predictors of ethnic identity and the relationship between ethnic identity and psychosocial adjustment. Perceptions of ethnicity and ethnic identity and measures of psychosocial adjustment were obtained from 82 Italian-Australian adolescents. Parents' maintenance of cultural ties was associated with a strong sense of ethnic identity, however ethnic identity was relatively unimportant in predicting psychosocial adjustment. Cultural variables such as parents' embeddedness in the Italian community, the desire to assimilate into the Australian culture, and the perception of problems arising from minority group membership were of greater significance.  相似文献   
992.
A new test for measuring the ability to perceive pictorial depth was used with children of two remote Bushman populations (!Xu and Kxoe), as well as with a sample of adult Bushmen drawn from these populations and a sample of urban Zulu children. The results show that subjects of apparently little sophistication are capable of perceiving depth when confronted with a ‘geometric’ figure. They also show surprising inter-group differences which cannot be easily explained by differences of environmental experience.  相似文献   
993.
Autobiographical memory in suicide attempters   总被引:4,自引:0,他引:4  
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994.
995.
The role of on-the-job experience in fostering skill at detecting deception was examined. A deception-detection test was administered to three samples of more than 100 subjects each: a group of undergraduates with no special experiences at detecting deceit; a group of new recruits to a federal law enforcement training program, who had some limited on-the-job experience at detecting deceit; and a group of advanced federal law enforcement officers, with years of experience working at jobs in which the detection of deception is very important. Although the officer samples were more confident about their judgments of deceptiveness than were the students, they were no more accurate than the students. None of the three groups showed a significant improvement in deception-detection success from the first half to the second half of the test; however, the advanced officers felt increasingly confident about their performance as they progressed through the test. Correlational analyses of the relationship between accuracy and confidence provided further evidence that experience does not improve people's awareness oi the accuracy or inaccuracy of their judgments. The findings from this research are compared to the results of research on other kinds of professional decision-makers (e.g., clinical psychologists), and several theoretical perspectives on the role of experience in decision making are discussed.  相似文献   
996.
We examined the effects of assigning a classroom manager's role on the frequency of social interactions and the sociometric standing of three withdrawn kindergarten students. Results showed that when the three socially withdrawn students were placed in the manager's role they substantially increased the frequency of their positive social initiations during free-play time, were the recipients of many more positive and significantly fewer negative social bids from their peers, were rated more favorably by their classmates on a sociometric rating scale, and were selected more frequently as best friends by their peers. In addition, follow-up data suggested partial maintenance of treatment effects when students no longer occupied manager positions.  相似文献   
997.
Pigeon's observational learning of successive visual discrimination was studied using within-subject comparisons of data from three experimental conditions. Two pairs of discriminative stimuli were used; each bird was exposed to two of the three experimental conditions, with different pairs of stimuli used in a given bird's two conditions. In one condition, observers were exposed to visual discriminative stimuli only. In a second condition, subjects were exposed to a randomly alternating sequence of two stimuli where the one that would subsequently be used as S+ was paired with the operation of the grain magazine. In a third experimental condition, subjects were exposed to the performance of a conspecific in the operant discrimination procedure. After exposures to conspecific performances, there was facilitation of discriminative learning, relative to that which followed exposures to stimulus and reinforcement sequences or exposures to stimulus sequences alone. Exposure to stimulus and food-delivery sequences enhanced performance relative to exposure to stimulus sequences alone. The differential effects of these three types of exposure were not attributable to order effects or to task difficulty; rather, they clearly were due to the type of exposure.  相似文献   
998.
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   
999.
Three experiments describe the effects of manipulating the frequency of response-reinforcer contiguity in a recycling conjunctive schedule. The schedule arranged that a reinforcer was delivered after 30 s provided at least one response had occurred; otherwise the next cycle started immediately. In Experiment 1, this schedule produced the typical pause–respond–pause pattern, with most responses at mid-interval; and, when a limited number of contiguities between responses and food delivery were added, the pattern became more like the monotonic scallop seen on fixed-interval schedules. In Experiment 2, the schedule was initially presented with an additional contingency that allowed contiguity on every trial. Fixed-interval-like behavior occurred and tended to persist as contiguities were gradually eliminated. In Experiment 3, the recycling conjunctive schedule alternated with a condition in which a large number of contiguities occurred. The pause–respond–pause pattern and fixed-interval-like performance occurred with few or many contiguities, respectively. The results of all three experiments illustrate how contiguity interacts with a small number of other variables to determine performance on interval schedules and illuminate previous findings with fixed-interval and fixed-time schedules.  相似文献   
1000.
Thirty-one college undergraduates learned to touch abstract stimuli on a computer screen in arbitrarily designated “correct” sequential orders. Four sets of seven stimuli were used; the stimuli were arrayed horizontally on the screen in random sequences. A correct response (i.e., touching first the stimulus designated as first) resulted in that stimulus appearing near the top of the screen in its correct sequential position (left to right), and remaining there until the end of the trial. Incorrect responses (i.e., touching a stimulus out of sequence) terminated the trial. New trials displayed either the same sequence as the one on which an error had occurred (same-order correction procedure), or a new random sequence (new-order correction procedure). Whenever all responses occurred in the correct sequence, the next trial displayed a new random sequence. Each phase ended when five consecutive correct response sequences occurred. Initially, the same-order correction procedure increased control by the position as well as by the shape of the stimuli; also, it produced more errors, more total trials, more trials to mastery, and more individual patterns of reacquisition than were produced by the new-order procedure.  相似文献   
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