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891.
892.
Stress-processes and depressive symptomatology   总被引:5,自引:0,他引:5  
  相似文献   
893.
894.
The purpose of the present paper was to determine whether people encode relations among component features in experience, or whether they simply encode the occurrence of features separately as independent cues. This has become a major issue in theories of concept-formation at the present time. It is suggested in this paper that two problems have particularly obstructed a clear resolution of the issue. The first is a consistent failure to check to what extent training materials actually contain relations among features, before results are declared in favour of a particular model. The second is the use, hitherto, of only informal methods of analysing such relations, where they exist, and of predicting from them the structure of the concept. This paper describes an expression for measuring the overall relations among feature-variables in concept training materials. It also introduces a methodology, using log-linear models, for predicting concept structures on the basis of those relations. An experiment combined these methods to assess whether subjects abstracted relations among features, or whether they abstracted independent cues. A subsidiary aim was to assess how feedback, based on independent-cue information, during learning, affected the construction of the concept. The results came out strongly in favour of relational-coding and there was some evidence that feedback based on independent-cues retarded concept formation.  相似文献   
895.
Autobiographical memory in suicide attempters   总被引:4,自引:0,他引:4  
  相似文献   
896.
897.
Two studies were conducted to investigate the effects of perceived control in two men's prisons, one housing 181 inmates and the other housing 623 inmates. In both prisons, inmates' perceived control over the environment was found to be significantly related to their ratings of their living accommodations, experienced stress, and physical symptoms, even when type of cell was held constant.  相似文献   
898.
Three students with moderate handicaps were taught to initiate and expand on conversational topics. The teaching procedure used stimuli generated from actual conversations with nonhandicapped peers. Generalization was assessed by audiotaping conversations between the handicapped students and their peers in natural school contexts without adult supervision. Results indicated that training generalized to natural contexts. These results were socially validated by undergraduate special education students, who rated tapes of two of the students' conversations during training phases as more socially competent than during baseline. Results are discussed in terms of the evaluation of complex social behavior as multioperant behaviors.  相似文献   
899.
Superimposition of response-independent reinforcement   总被引:6,自引:6,他引:0       下载免费PDF全文
Studies that have superimposed response-independent reinforcement (or reinforcers scheduled by contingencies placed on the absence of responding) upon conventional response-dependent schedules are reviewed. In general, providing alternative sources of reinforcement reduced response rates below the levels observed when alternative reinforcement was absent. However, response-rate elevation was sometimes found, particularly when rates of superimposed response-independent reinforcement were low. Superimposition of schedules providing reinforcers contingent on the absence of responding usually produced more severe response-rate decrements than superimposition of response-independent reinforcement. A variant of Herrnstein's equation, which assumes that some of the alternative reinforcers function as if they were delivered by baseline response-dependent source of reinforcement, is in qualitative agreement with the overall body of results obtained, and can predict both increases and decreases in response rate as resulting from superimposed reinforcers.  相似文献   
900.
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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