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951.
In repeated sampling enquiries application of method of successive sampling with partial replacement of units is advantageous. In this paper use of successive sampling technique when the sampling design is multi-stage has been studied. Estimates of population mean and its variance have been obtained (a) on the second occasion, and (b) on the h-th occasion under two systems of replacement, namely (i) by retaining only a fraction p of psu's along with their sample of ssu's, and (ii) by retaining all the psu's on the second occasion, but from each psu only a fraction p of the ssu's within them is retained. A cost function suitable to the design has been illustrated, with the help of data collected from a sample survey conducted by the Indian Council of Agricultural Research.  相似文献   
952.
Summary Using four detailed and complex simulation models we derive a framework for predicting behavior of any defoliating insect/forest system. The framework uses simple and easily gathered biological information on four sets of state variables, each with a characteristic temporal scale, to predict presence, absence or form of key ecological processes acting on or between the variables. The combination of these key processes enables prediction of system equilibrium structure and this structure can be used to derive the temporal behavior of the system. Four qualitatively different classes of system behavior arise from the equilibrium structures. The framework is tested against twelve other systems and field invalidation experiments are outlined. Forest defoliator research and management implications are discussed.  相似文献   
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Based upon research in an alcoholism treatment organization, the study explores the impact of interdisciplinary team treatment on organizational participants and structure. The findings suggest that alternate organizational arrangements are necessary for organizations which use the team method. The implications of team treatment for professionals were confounded because of power relationships within the organization. Role bargaining between professionals was observed to be virtually non-existent because of the dominance of a single discipline. A surprising finding was the extent to which supervisory personnel were disadvantaged in the study. Caution is suggested for those organizations most likely to adopt the team method, large public health organizations.  相似文献   
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The existing empirical literature on the outcomes of marital and pre-marital enrichment programs is critically reviewed. While the majority of studies have used untreated control groups and appear to offer very striking evidence of meaningful change as a result of these enrichment experiences, several important methodological deficiencies are common to these investigations and, therefore, require a cautious optimism about the efficacy of these programs. Six specific issues are addressed in an effort to improve the quality and utility of further research and practice in this area.  相似文献   
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This study provides additional information about casino gambling practices in two adolescent samples. Specifically, 109 adolescents from a religious high school and 84 adolescents from a juvenile detention facility in Las Vegas, Nevada were surveyed. Of these, 71 (36.8%) were found to gamble regularly (58 males, 13 females, mean age 15.9 years). Results indicated many similarities among the two groups. The overall sample appeared to have a strong affinity for casino gambling, were diverse in their practices and reasons for gambling, reported a variety of emotional and physiological behaviors when gambling, occasionally experienced problems from casino gambling, and had parents who generally approved and were aware of their children's gambling behavior. The accessibility and family-oriented nature of many new casinos may be responsible for these effects.The authors thank Nicole Giangregorio and Ned C. Silver for their assistance. Portions of this paper were presented at the meeting of the Rocky Mountain Psychological Association, Boulder, CO.  相似文献   
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