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作者：Javaras, Kristin N.; Ripley, Brian D.
作者单位：University of Oxford
摘要：Likert attitude data consist of responses to favorable and unfavorable statements about an entity. where responses fall into ordered categories ranging from disagreement to agreement. Social science and rnarketing researchers frequently use data of this type to measure attitudes toward an entity such as a policy or product. We focus oil data on American and British attitudes toward their respective nations (national pride). We introduce a multidimensional Unfolding model (MUM) to describe the ...
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作者：Rosenbaum, Paul R.; Ross, Richard N.; Silber, Jeffrey H.
作者单位：University of Pennsylvania; University of Pennsylvania; Pennsylvania Medicine; Childrens Hospital of Philadelphia; University of Pennsylvania
摘要：In observational studies of treatment effects, matched samples have traditionally been constructed using two tools, namely close matches on one or two key covariates and close matches on the propensity score to stochastically balance large numbers of covariates. Here we propose a third tool, fine balance, obtained using the assignment algorithm in a new way. We use all three tools to construct a matched sample for an ongoing study of provider specialty in the treatment of ovarian cancer. Fine ...
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作者：Rosenbaum, Paul R.
作者单位：University of Pennsylvania
摘要：In a randomized experiment comparing two treatments, there is interference between units if applying the treatment to one unit may affect other units. Interference implies that treatment effects are not comparisons of two potential responses that a unit may exhibit, one under treatment and the other under control, but instead are inherently more complex. Interference is common in social settings where people communicate, compete, or spread disease; in studies that treat one part of an organism...
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作者：Miller, Robert N.
作者单位：Oregon State University
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作者：Rappold, Ana Grohovac; Lavine, Michael; Lozier, Susan
作者单位：Duke University; United States Environmental Protection Agency; Duke University
摘要：This article describes a Bayesian statistical analysis of long-term changes in the depth of the ocean's mixed layer. The data are thermal profiles recorded by ships. For these data, there is no good sampling model and thus no obvious likelihood function. Our approach is to elicit posterior distributions for training data directly from the expert. We then infer the likelihood function and use it on large datasets.
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作者：Wang, Lifeng; Shen, Xiaotong
作者单位：University of Minnesota System; University of Minnesota Twin Cities
摘要：Binary support vector machines (SVMs) have been proven to deliver high performance. In multiclass classification, however, issues remain with respect to variable selection. One challenging issue is classification and variable selection in the presence of variables in the magnitude of thousands, greatly exceeding the size of training sample. This often occurs in genomics classification. To meet the challenge, this article proposes a novel multiclass support vector machine, which performs classi...
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作者：Sun, Wenguang; Cai, T. Tony
作者单位：University of Pennsylvania; University of Pennsylvania
摘要：We develop a compound decision theory framework for multiple-testing problems and derive an oracle rule based on the z values that minimizes the false nondiscovery rate (FNR) subject to a constraint on the false discovery rate (FDR). We show that many commonly used multiple-testing procedures, which are p value-based, are inefficient, and propose an adaptive procedure based on the z values. The z value-based adaptive procedure asymptotically attains the performance of the z value oracle proced...
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作者：Cheng, Ming-Yen; Peng, Liang
作者单位：National Taiwan University; University System of Georgia; Georgia Institute of Technology
摘要：Local likelihood modeling is a unified and effective approach to establishing the dependence of a response variable, which can be of various types, on independent variables. Therefore, these models have become popular in a wide range of applications. There is an increasing interest in employing multiparameter local likelihood models to investigate trends of sample extremes in environmental statistics. When sample maxima are modeled by a generalized extreme value distribution, the sample size i...
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作者：Hinich, Melvin J.; Serletis, Apostolos
作者单位：University of Texas System; University of Texas Austin; University of Calgary
摘要：This article uses daily observations for the Canadian dollar-U.S. dollar nominal exchange rate over the recent flexible exchange rate period and a new statistical technique, recently developed by Hinich, to detect major political and economic events that have affected the exchange rate.
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作者：Tymofyeyev, Yevgen; Rosenberger, William F.; Hu, Feifang
作者单位：Merck & Company; Merck & Company USA; George Mason University; University of Virginia; University of Virginia
摘要：For sequential experiments with K treatments, we establish two formal optimization criteria to find optimal allocation strategies. Both criteria involve the sample sizes on each treatment and a concave noncentrality parameter from a multivariate test. We show that these two criteria are equivalent. We apply this result to specific questions: (1) How do we maximize power of a multivariate test of homogeneity with binary response?, and (2) for fixed power, how do we minimize expected treatment f...
