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Constraint redundancy (Rc) was varied in order to manipulate the statistical structure of sets of patterns. Measures of pattern features and Rc were related to the categorization by Ss who had experienced different types of preexposure to sets of patterns from the same stimulus domain. Both Rc and pattern measures were related to the categories produced by Ss in a schematic-concept-formation (SCF) task.  相似文献   
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Assuming the phi-gamma hypothesis, deductions concerning the method of limits (ML) are derived. For a given step size, the selection of the initial stimulus for ascending series or for descending series has little effect on the summary statistical measures of the ML. Estimates of ML statistics are derived for different step sizes, and these estimates are used to estimate the mean and standard deviation of the phi-gamma hypothesis. Also considered are how summary statistical measures of the ML are influenced by extremely large and small step sizes and by the definition of a ML threshold.  相似文献   
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A Systems Dilemma   总被引:1,自引:0,他引:1  
The current shift of interest, reflected in public policy, from the production of goods to the provision of services, has caused a major re-examination of the nature of the services the individual can expect from his society. This re-examination is producing a number of insights, some of them shocking. In particular, we are learning that many of the systems we have created to deliver services are, in the name of “progress” and “civilization,” contributing to the conditions of human distress they were designed to alleviate. Much has been written lately about how service systems of one kind or another subvert their announced goals—how a welfare system perpetuates poverty, or how the medical profession creates iatrogenic illness. There has not been very much written, however, about how several systems inadvertently combine in their day to day operations in such a way as to frustrate each others' activities, and how, in so doing, they destroy in varying degrees the lives of people, or render it difficult for them to improve their lives. We have all been much too tightly locked in our own niches by training, experience, and various types of private interest to see this kind of interlock. It comes into sharp perspective only when one studies the problems of a single person in terms of his total life space, his “ecology.” This paper represents an effort to describe one such situation in a family as viewed from a community health services program designed to approach human crises as ecological phenomena, and to explore and respond to them within this framework. We have found that the best way to organize our view of the environmental field people move in is according to the diverse systems which make it up, so we have labeled our theoretical base “ecological systems theory.” ( 1 ) What is of particular interest to the behavioral scientist in the situation described is that neither individual nor family diagnosis, nor the contributions of the larger systems (in this case a housing system and a system of medical care) will, if viewed separately, explain the state of the man in question. Only when the contributions of all of these systems are made clear, and their interrelationships explored, do the origins of the phenomena described begin to emerge.  相似文献   
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