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The matching identification problem (MIP) is a combinatoric search problem related to the fields of learning from examples, boolean functions, and knowledge acquisition. The MIP involves identifying a single “goal” item from a large set of items. Because there is commonly a cost associated with evaluating each guess, the goal item should be identified in as few guesses as possible. As in most search problems, the items have a similar structure, which allows an evaluation of each guessed item. In other words, each guessed item elicits partial information about the goal item, i.e. how similar the guess is to the goal. With this information the goal is more quickly identified.The unordered MIP has been studied by Mehrez and Steinberg (ORSA J. Comput. 7 (1995) 211) in which they proposed two different types of algorithms. The purpose of the present paper is to suggest an improved Spanning Heuristic algorithm. Its improvement increases as the problem size increases. Further results and comparisons are derived for the unordered and ordered cases.This research shows that when the search space is very large, it is better to inquire from items that are known not to be the goal (they have been ruled out by previous guesses), for the purpose of acquiring more information about the goal. As the search space is narrowed, it is better to guess items that have not been ruled out.  相似文献   
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The purpose of this project is to better understand poverty and social exclusion of psychiatric survivors using a capabilities approach to social justice as part of a larger mixed-methods longitudinal study (N=380) in Ontario, Canada. Using thematic coding, four themes emerged: poverty, ‘You just try to survive’; stigma, ‘People treat you like trash’; belonging, ‘You feel like you don’t belong’; and shared concern and advocacy, ‘Everyone deserves housing’. This analysis provides a deeper understanding of poverty and other social determinants of experiences of psychiatric survivors, including the synergism of poverty and social exclusion.  相似文献   
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This study examined the effect of Testofen, a specialised Trigonella foenum-graecum seed extract on the symptoms of possible androgen deficiency, sexual function and serum androgen concentrations in healthy aging males. This was a double-blind, randomised, placebo-controlled trial involving 120 healthy men aged between 43 and 70 years of age. The active treatment was standardised Trigonella foenum-graecum seed extract at a dose of 600?mg/day for 12 weeks. The primary outcome measure was the change in the Aging Male Symptom questionnaire (AMS), a measure of possible androgen deficiency symptoms; secondary outcome measures were sexual function and serum testosterone. There was a significant decrease in AMS score over time and between the active and placebo groups. Sexual function improved, including number of morning erections and frequency of sexual activity. Both total serum testosterone and free testosterone increased compared to placebo after 12 weeks of active treatment. Trigonella foenum-graecum seed extract is a safe and effective treatment for reducing symptoms of possible androgen deficiency, improves sexual function and increases serum testosterone in healthy middle-aged and older men.  相似文献   
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Literaturbesprechungen

Soziologische Theorie, Handlungstheorie, Methoden, Familiensoziologie, Sozialstrukturanalyse, Raumsoziologie, Stadtsoziologie, Ged?chtnissoziologie, Religionssoziologie  相似文献   
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We investigate special cases of the quadratic minimum spanning tree problem (QMSTP) on a graph \(G=(V,E)\) that can be solved as a linear minimum spanning tree problem. We give a characterization of such problems when G is a complete graph, which is the standard case in the QMSTP literature. We extend our characterization to a larger class of graphs that include complete bipartite graphs and cactuses, among others. Our characterization can be verified in \(O(|E|^2)\) time. In the case of complete graphs and when the cost matrix is given in factored form, we show that our characterization can be verified in O(|E|) time. Related open problems are also indicated.  相似文献   
7.
We propose a class [I,S] of loss functions for modeling the imprecise preferences of the decision maker in Bayesian Decision Theory. This class is built upon two extreme loss functions I and S which reflect the limited information about the loss function. We give an approximation of the set of Bayes actions for every loss function in [I,S] and every prior in a mixture class; if the decision space is a subset of , we obtain the exact set.  相似文献   
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Abstract

This article describes the evolution of a research program across 18 PhD dissertations over a period of eleven years. Included in this paper is a discussion of the advantages and disadvantages of student and field participation in thematic experimental research. The essential steps in the development of a set of related dissertations also are described. The guidelines for constructing the true experiment as dissertation are outlined. Attention is paid to the resources required to carry out thematic research and the specific ways in which such dissertations have been funded. Characteristics of those students who can best avoid such an approach to a dissertation are examined. Finally the author looks at the product of these dissertations and dissertators in terms of contribution to knowledge, the creation of practitioner manuals for practice interventions, the formation of practice-research faculty, research productivity of these faculty, and the development of the dissertator's clinical skills.  相似文献   
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A simple modification is suggested for the construction of transfer function models relating an output variable Yt to an input variable Xt when the model for Xt contains operators that cancel out. In addition, the evaluation of transfer function models is discussed by comparing the forecasts with the actual observations.  相似文献   
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