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991.
992.
Pigeons were trained in delayed matching-to-sample with two postsample stimuli. A postsample R-cue signaled that a matching choice phase would follow. A postsample F-cue signaled that a matching choice phase would not follow. Previous research found reduced matching accuracy on F-cued probe trials when comparison stimuli were presented in the choice phase. The present four experiments systematically varied the events following an F-cue to determine the conditions under which the F-cue reduces delayed-matching accuracy. When F-cues and R-cues controlled different behavior, matching on probe trials was poor. When both cues controlled the same behavior, matching on probe trials was good. This result is best explained by the theory that comparison stimuli retrieve the sample representation, but only in the behavioral context established by the R-cue. The present research supports the view that response-produced stimuli serve a contextual role in animal short-term memory.  相似文献   
993.
Data were collected about research issues involving laboratory and field settings through a content analysis of the 1966, 1970, and 1974 volumes of the Journal of Applied Psychology, Organizational Behavior and Human Performance, and Personnel Psychology. Four general categories of data were collected: (a) affiliation of investigators, (b) topic areas investigated, (c) settings of the research, and (d) research strategies employed. Four common beliefs of either laboratory or field advocates were contradicted by the data. First, laboratory research was found fairly frequently in the industrial-organizational literature. Second, theory and hypothesis testing were not overemphasized. Third, laboratory research was as applied as field research. Lastly, studies published by researchers with nonacademic affiliations were as likely to have been conducted in laboratory settings as field settings. Recommendations were made to use the laboratory more frequently for theory and hypothesis based research and to use a variety of research strategies in both laboratory and field settings.  相似文献   
994.
Conclusion In the present article I have surveyed several approaches to modeling the clinical diagnostic process. I have argued that at this point of the field's development, logics which simulate the reasoning patterns and knowledge base of expert clinicians represent research programs that are most likely to succeed. No logic of diagnosis has yet attained the status of being definitive; in spite of striking progress much more research and testing is required. On the basis of various existing logics, I have attempted to articulate a number of desiderata which an ideal diagnostic logic should satisfy. In spite of these criticisms, I would maintain that programs such as MYCIN and INTERNIST have already matured to the point where they are useful both in consultations and in teaching diagnostic reasoning.Department of History and Philosophy of Science, University of Pittsburgh, Pittsburgh, PA 15260. The author wishes to acknowledge gratefully the assistance of Drs. Jack D. Myers, Harry E. Pople, Jr., Joshua Nagin, and Randy Miller with the research that resulted in this essay and thanks to L. J. Cohen, J. F. Fries, R. N. Giere, and C. Whitbeck for comments on an earlier draft. Supported in part by training grant MB 00199-01 from the Bureau of Health Manpower (DHEW) and by the National Science Foundation and the National Endowment for the Humanities.Presented at a symposium on Philosophy and Medicine held at the American Philosophical Association's Eastern Division Meeting in Washington, D.C., December 27–29, 1978. This essay partially overlaps with an article on Problems in computer diagnosis to appear inThe Ethics of Diagnosis, H. T. Engelhardt, Jr. and S. Spicker (eds.) Dordrecht: D. Reidel, forthcoming.  相似文献   
995.
Sensitivity to grammatical structure in so-called agrammatic aphasics   总被引:9,自引:0,他引:9  
Comprehension failures in agrammatic aphasics, as well as their difficulties in sentence construction, have been attributed to an underlying deficit involving the retrieval of syntactic structure. In this study we show that four agrammatic patients display a remarkable sensitivity to structural information, as indicated by their performance on a grammaticality judgment task. These results indicate significant sparing of syntactic knowledge in agrammatism, and suggest that the sentence comprehension disturbances in these patients do not reflect loss of the capacity to recover syntactic structure. In particular, accounts of the comprehension deficit in agrammatism that implicate a failure to exploit information carried by the closed class (function word) vocabulary are called seriously into question. Alternative explanations of the comprehension problem in agrammatism are explored.  相似文献   
996.
The question of whether an automatic detection task requires the use of limited-capacity resources was investigated in a series of dual-task experiments. The automatic task required subjects to detect a consistently mapped target digit in a display of letters. This task was paired with a variety of concurrent visual discriminations that could either occur in close proximity to the automatic target or in a disparate display area. The main finding was that accuracy in each task was higher in conditions allowing attention to be shared than when it had to be divided between separate areas. These results indicate that detection of automatic targets depends on the allocation of spatial attention to the target's area.  相似文献   
997.
998.
This article discusses the use of the Eureka for those seeking employment during the current economic trends affecting the labor market. Clients using this approach will be exposed to a wider variety of occupational options, thus expanding their range of realistic choices. The Eureka offers direction and current reliable information about the labor market in a short period of time.  相似文献   
999.
Child care workers were trained in specified techniques (play manager routines) in an effort to increase purposeful activity among a group of profoundly and severely retarded institutionalized boys. A system of prompts, increasing the availability of toys and regular staff monitoring, were alternated with normal institutional routines in an ABA reversal design. On the average, activity level increased from 10% to a mean of 70% during treatment conditions. Correspondingly, stereotyped or harmful behaviors decreased from an average of 20% to 70% during treatment.  相似文献   
1000.
Two experiments are reported in which the relationship between compliance with “do” and “don't” requests was examined with developmentally disabled children. In Experiment 1, a multiple baseline design across subjects with counterbalanced treatment conditions was used to evaluate a compliance training program composed of four phases: (a) baseline, during which no consequences were delivered for compliance, (b) reinforcement for compliance with one targeted “do” request, (c) reinforcement for compliance with one targeted “don't” request, and (d) follow-up with reinforcement on a variable ratio schedule for compliance with any “do” or “don't” request. Results of probes conducted before and after training within each condition indicated that generalized compliance occurred only with requests of the same type as the target exemplar (“do” or “don't”). In Experiment 2, these results were replicated in a classroom setting. Following collection of baseline probe data on student compliance, a teacher training program was successfully implemented to increase reinforcement of compliance first with one “do” and subsequently with one “don't” request of a target student. Results of multiple baseline probes across “do” and “don't” requests indicated that the teacher generalized and maintained reinforcement of compliance with other requests of the same type and to other students, with a resulting increase in student compliance with the type of requests reinforced. The impact of treatment on both teacher and student behavior was socially validated via consumer ratings. Implications of these findings with respect to response class formation and compliance training programs are discussed.  相似文献   
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