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101.
William R. Shadish Kevin Ragsdale Renita R. Glaser Linda M. Montgomery 《Journal of marital and family therapy》1995,21(4):345-360
This article reviews the major findings from a multiproject meta-analysis of the effects of marital and family therapy (MFT). Across 163 randomized trials, MFT demonstrates moderate, statistically significant, and often clinically significant effects. No orientation is yet demonstrably superior to any other, nor is MFT superior to individual therapy. Cost effectiveness information is scant in these 163 studies, but supportive. Randomized experiments yield very different answers from nonrandomized experimental studies of the effects of MFT, calling into question whether we should mix the two in reviews. We have also found several new differences in the ways that marital therapy (MT) and family therapy (FT) studies are conducted, making them harder to compare. Finally, important questions still exist about whether any psychotherapy, including MFT, yet has sufficient information about how well research generalizes to everyday clinical practice. 相似文献
102.
D. R. Wingo 《Statistical Papers》1993,34(1):271-276
In a recent paper in this journal, Lee, Kapadia and Brock (1980) developed maximum likelihood (ML) methods for estimating the scale parameter of the Rayleigh distribution from doubly censored samples. They reported convergence difficulties in attempting to solve numerically the nonlinear likelihood equation (LE). To mitigate these difficulties, they employed approximations to simplify the LE, but found that the solution of the resulting simplified equation can give rise to parameter estimates of erratic accuracy. We show that the use of approximations to simplify the LE is unnecessary. In fact, under suitable parametric transformation, the log-likelihood function is strictly concave, the ML estimate always exists, is unique and finite. Furthermore, the LE is easy to solve numerically. A numerical example is given to illustrate the computations involved. 相似文献
103.
A table is presented for the construction and selection of tightened-normal-tightened sampling scheme of type TNT-(n1, n2;c). Efficiency of TNT-(n1, n2;c) scheme over conventional single and double sampling plans is discussed. 相似文献
104.
105.
Margaret R. Somers 《Theory and Society》1994,23(5):605-649
106.
Melissa S. Waters R. Carter Hill William J. Moore Robert J. Newman 《Journal of Labor Research》1994,15(4):355-372
This paper estimates a simultaneous-equations model with public sector bargaining laws and union membership treated as jointly-determined
variables. The extent of public sector unionization has a significant positive influence on the passage of prolabor bargaining
legislation and bargaining legislation has strong, independent effects on the extent of public sector unionization.
We gratefully acknowledge the research support provided by Minbo Kim and Parisun Chantonahom. 相似文献
107.
樊宝敏 《北京林业大学学报(社会科学版)》2003,2(3):69-74
张钧成先生是我国著名的林业历史学家.该文从林业史学科建设、林业史研究概况、中国古代林业通史、中国古代林业思想和传统文化、林业科技史和经济史、近现代林业史等研究领域,概述了张先生的学术成就,并回顾了张先生高尚的人生哲学和宝贵的治学经验.张先生的研究成果和治学经验,为我国林史学科的发展奠定了基础. 相似文献
108.
This paper studies a single-product distribution channel where a supplier manufactures items of a given type, some of which are defective, that are sold by a retailer who only detects a subset of the defective items, passing the rest along to customers. We conjecture the structure of the demand and cost functions, assuming customers to have a decreasing marginal aversion to bad quality while both the supplier and the retailer make marginally increasing efforts to avoid bad quality. This allows us to deduce several implicit parameters of a cost model based on observable data, such as the share of the channel margin. Once the parameters of the model are available, we analyze the result of vertical integration. Although we confirm the well-known fact that vertical integration improves the quality perceived by the customer, we characterize the supplier's decision of whether or not to provide a better quality in terms of the individual channel margins. As an alternative, we derive the conditions under which the supplier and the retailer may devise a mutually beneficial transfer contract that simultaneously increases their profit and improves quality. 相似文献
109.
110.
Chris Dockins Robin R Jenkins Nicole Owens Nathalie B Simon Lanelle Bembenek Wiggins 《Risk analysis》2002,22(2):335-346
This article explores two problems analysts face in determining how to estimate values for children's health and safety risk reductions. The first addresses the question: Do willingness‐to‐pay estimates for health risk changes differ across children and adults and, if so, how? To answer this question, the article first examines the potential effects of age and risk preferences on willingness to pay. A summary of the literature reporting empirical evidence of differences between willingness to pay for adult health and safety risk reductions and willingness to pay for health and safety risk reductions in children is also provided. The second dimension of the problem is a more fundamental issue: Whose perspective is relevant when valuing children's health effects—society's, children's, adults‐as‐children, or parents'? Each perspective is considered, followed ultimately by the conclusion that adopting a parental perspective through an intrahousehold allocation model seems closest to meeting the needs of the estimation problem at hand. A policy example in which the choice of perspective affects the outcome of a regulatory benefit‐cost analysis rounds out the article and emphasizes the importance of perspective. 相似文献