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作者：Li, Hongzhe; Hong, Fangxin
作者单位：University of Pennsylvania; Salk Institute
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作者：Yuan, Ming; Kendziorski, Christina
作者单位：University System of Georgia; Georgia Institute of Technology; University of Wisconsin System; University of Wisconsin Madison
摘要：Among the first microarray experiments were those measuring expression over time, and time course experiments remain common. Most methods to analyze time course data attempt to group genes sharing similar temporal profiles within a single biological condition. However. with time course data in multiple conditions, a main goal is to identify differential expression patterns over time. An intuitive approach to this problem would be to apply at each time point any of the many methods for identify...
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作者：Tan, Zhiqiang
作者单位：Johns Hopkins University; Johns Hopkins Bloomberg School of Public Health
摘要：Drawing inferences about the effects of treatments and actions is a common challenge in economics, epidemiology, and other fields. We adopt Rubin's potential outcomes framework for causal inference and propose two methods serving complementary purposes. One can be used to estimate average causal effects, assuming no confounding given measured covariates. The other can be used to assess how the estimates might change under various departures from no confounding. Both methods are developed from ...
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作者：Guan, Yongtao
作者单位：Yale University
摘要：We propose a new likelihood-based approach in fitting spatial point process models. A composite likelihood is first formed by adding some pairwise composite likelihood functions that are defined in terms of the second-order intensity function of the underlying process, and then used for estimating the unknown parameters. The estimation procedure is computationally simple and yields consistent and asymptotically normal estimators under some mild conditions. We demonstrate through a simulation s...
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作者：Arnold, Barry C.; Castillo, Enrique; Sarabia, Jose Maria
作者单位：University of California System; University of California Riverside; Universidad de Cantabria; Universidad de Cantabria
摘要：Recently, Jones pointed out a useful device for enriching families of univariate distributions. Typically, one may construct a random variable with distribution F by considering F-1 (U), where U is a uniform(0, 1) random variable. Jones suggested replacing the uniform random variable by a beta-distributed random variable. In this article an analogous enriching process is applied to the Rosenblatt construction of multivariate distributions. Several parametric families are introduced using this ...
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作者：Singpurwalla, Nozer D.
作者单位：George Washington University
摘要：This is an expository article directed at reliability theorists, survival analysts, and others interested in looking at life history and event data. Here we introduce the notion of a hazard potential as an unknown resource that art item is endowed with at inception. The item fails when this resource becomes depleted. The cumulative hazard is a proxy for the amount of resource consumed, and the hazard function is a proxy for the rate at which this resource is consumed. With this conceptualizati...
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作者：Woo, Mi-Ja; Sriram, T. N.
作者单位：University System of Georgia; University of Georgia
摘要：In many applications, it is important to find the mixture with fewest number of components, known as the mixture complexity, that provides a satisfactory fit to the data. This article focuses on developing an estimator of mixture complexity that is consistent when the form of component densities are unknown but are postulated to be members of some parametric family and is simultaneously robust against model misspecification. We treat the estimation of mixture complexity as a model selection pr...
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作者：Hjort, Nils Lid; Claeskens, Gerda
作者单位：University of Oslo; Universite Catholique Louvain; Universite Catholique Louvain
摘要：This article is concerned with variable selection methods for the Cox proportional hazards regression model. Including excessive covariates causes extra variability and inflated confidence intervals for regression parameters; thus regimes for discarding the less informative ones are needed. Our framework has p covariates designated as protected, while variables from a further set of q covariates are examined for possible inclusion or exclusion. We develop a focused information criterion (FIC) ...
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作者：Lu, Wilson W.; Brick, J. Michael; Sitter, Randy R.
作者单位：Westat; Simon Fraser University
摘要：A jackknife or balanced repeated replication variance estimator in a large survey typically requires a large number of replicates and replicate weights. Reducing the number of replicates may have important advantages for computations and for limiting the risk of data disclosure from public use data files. This article proposes algorithms adapted from scheduling theory to combine variance strata and, thus, reduce the number of replicates. The algorithms are simple and efficient and can be adapt...
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作者：Mao, Chang Xuan
作者单位：University of California System; University of California Riverside
摘要：Estimating the number of species in a population from a sample of individuals is investigated in a nonparametric Poisson mixture model. A sequence of lower bounds to the odds that a species is unseen in the sample are proposed from a geometric perspective. A lower bound and its representing mixing distribution can be computed by linear programming with guaranteed convergence. These lower bounds can be estimated by the maximum likelihood method and used to construct lower confidence limits for ...
