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作者：Weinstein, Asaf; Ma, Zhuang; Brown, Lawrence D.; Zhang, Cun-Hui
作者单位：Stanford University; University of Pennsylvania; University of Pennsylvania; Rutgers University System; Rutgers University New Brunswick
摘要：The problem of estimating the mean of a normal vector with known but unequal variances introduces substantial difficulties that impair the adequacy of traditional empirical Bayes estimators. By taking a different approach that treats the known variances as part of the random observations, we restore symmetry and thus the effectiveness of such methods. We suggest a group-linear empirical Bayes estimator, which collects observations with similar variances and applies a spherically symmetric esti...
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作者：Basse, Guillaume; Feller, Avi
作者单位：Harvard University; University of California System; University of California Berkeley
摘要：Two-stage randomization is a powerful design for estimating treatment effects in the presence of interference; that is, when one individual's treatment assignment affects another individual's outcomes. Our motivating example is a two-stage randomized trial evaluating an intervention to reduce student absenteeism in the School District of Philadelphia. In that experiment, households with multiple students were first assigned to treatment or control; then, in treated households, one student was ...
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作者：Chib, Siddhartha; Shin, Minchul; Simoni, Anna
作者单位：Washington University (WUSTL); University of Illinois System; University of Illinois Urbana-Champaign; Institut Polytechnique de Paris; ENSAE Paris; Ecole Polytechnique; Centre National de la Recherche Scientifique (CNRS)
摘要：In this article, we develop a Bayesian semiparametric analysis of moment condition models by casting the problem within the exponentially tilted empirical likelihood (ETEL) framework. We use this framework to develop a fully Bayesian analysis of correctly and misspecified moment condition models. We show that even under misspecification, the Bayesian ETEL posterior distribution satisfies the Bernstein-von Mises (BvM) theorem. We also develop a unified approach based on marginal likelihoods and...
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作者：Happ, Clara; Greven, Sonja
作者单位：University of Munich
摘要：Existing approaches for multivariate functional principal component analysis are restricted to data on the same one-dimensional interval. The presented approach focuses on multivariate functional data on different domains that may differ in dimension, such as functions and images. The theoretical basis for multivariate functional principal component analysis is given in terms of a Karhunen-Loeve Theorem. For the practically relevant case of a finite Karhunen-Loeve representation, a relationshi...
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作者：Karwa, Vishesh
作者单位：University System of Ohio; Ohio State University
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作者：Krupskii, Pavel; Huser, Raphael; Genton, Marc G.
作者单位：King Abdullah University of Science & Technology
摘要：We propose a new copula model that can be used with replicated spatial data. Unlike the multivariate normal copula, the proposed copula is based on the assumption that a common factor exists and affects the joint dependence of all measurements of the process. Moreover, the proposed copula can model tail dependence and tail asymmetry. The model is parameterized in terms of a covariance function that may be chosen from the many models proposed in the literature, such as the Matern model. For som...
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作者：Li, Liang; Wu, Chih-Hsien; Ning, Jing; Huang, Xuelin; Shih, Ya-Chen Tina; Shen, Yu
作者单位：University of Texas System; UTMD Anderson Cancer Center; University of Texas System; UTMD Anderson Cancer Center
摘要：Estimating the average monthly medical costs from disease diagnosis to a terminal event such as death for an incident cohort of patients is a topic of immense interest to researchers in health policy and health economics because patterns of average monthly costs over time reveal how medical costs vary across phases of care. The statistical challenges to estimating monthly medical costs longitudinally are multifold; the longitudinal cost trajectory (formed by plotting the average monthly costs ...
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作者：Rybin, Denis; Lew, Robert; Pencina, Michael J.; Fava, Maurizio; Doros, Gheorghe
作者单位：Boston University; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard Medical School
摘要：In clinical trials, placebo response can affect the inference about efficacy of the studied treatment. It is important to have a robust way to classify trial subjects with respect to their response to placebo. Simple, criterion-based classification may lead to classification error and bias the inference. The uncertainty about placebo response characteristic has to be factored into the treatment effect estimation. We propose a novel approach that views the placebo response as a latent character...
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作者：She, Yiyuan; Wang, Zhifeng; Jiang, He
作者单位：State University System of Florida; Florida State University
摘要：Variable selection for models including interactions between explanatory variables often needs to obey certain hierarchical constraints. Weak or strong structural hierarchy requires that the existence of an interaction term implies at least one or both associated main effects to be present in the model. Lately, this problem has attracted a lot of attention, but existing computational algorithms converge slow even with a moderate number of predictors. Moreover, in contrast to the rich literatur...
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作者：Athey, Susan; Eckles, Dean; Imbens, Guido W.
作者单位：Stanford University; National Bureau of Economic Research; Massachusetts Institute of Technology (MIT)
摘要：We study the calculation of exact p-values for a large class of nonsharp null hypotheses about treatment effects in a setting with data from experiments involving members of a single connected network. The class includes null hypotheses that limit the effect of one unit's treatment status on another according to the distance between units, for example, the hypothesis might specify that the treatment status of immediate neighbors has no effect, or that units more than two edges away have no eff...
