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作者:Rosenbaum, P. R.
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作者:Fang, Fang; Shao, Jun
作者单位:East China Normal University
摘要:Existing methods for handling nonignorable missing data rely on the correct specification of parametric models, which is difficult to check. By utilizing the information carried in an instrument, we propose a novel model selection criterion, called the penalized validation criterion, in the presence of nonignorable nonresponse with unspecified propensity. The proposed method can consistently select the most compact correct parametric model from a group of candidate models if one of the candida...
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作者:Som, Agniva; Hans, Christopher M.; MacEachern, Steven N.
作者单位:Duke University; University System of Ohio; Ohio State University
摘要:The development of prior distributions for Bayesian regression has traditionally been driven by the goal of achieving sensible model selection and parameter estimation. The formalization of properties that characterize good performance has led to the development and popularization of thick-tailed mixtures of g priors such as the Zellner-Siow and hyper-g priors. In this paper we introduce a conditional information asymptotic regime that is motivated by the common data analysis setting where at ...
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作者:Ding, Peng; Vanderweele, Tyler J.
作者单位:University of California System; University of California Berkeley; Harvard University; Harvard T.H. Chan School of Public Health
摘要:It is often of interest to decompose the total effect of an exposure into a component that acts on the outcome through some mediator and a component that acts independently through other pathways. Said another way, we are interested in the direct and indirect effects of the exposure on the outcome. Even if the exposure is randomly assigned, it is often infeasible to randomize the mediator, leaving the mediator-outcome confounding not fully controlled. We develop a sensitivity analysis techniqu...
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作者:Cox, D. R.
作者单位:University of Oxford
摘要:An outline account is given of the work of nine major figures working mostly in the earlier two-thirds of the 20th century. Some comments are included about their personal characteristics.
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作者:Nemeth, Christopher; Sherlock, Chris; Fearnhead, Paul
作者单位:Lancaster University
摘要:In this paper we propose a new sampling scheme based on Langevin dynamics that is applicable in pseudo-marginal and particle Markov chain Monte Carlo algorithms. We investigate the algorithm's theoretical properties under standard asymptotics, which correspond to an increasing dimension n of the parameters. Our results show that the behaviour of the algorithm depends crucially on how accurately one can estimate the gradient of the log target density. If the error in the estimate of the gradien...
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作者:Xie, Yuying; Liu, Yufeng; Valdar, William
作者单位:Michigan State University; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina; University of North Carolina Chapel Hill
摘要:Gaussian graphical models are widely used to represent conditional dependencies among random variables. In this paper, we propose a novel estimator for data arising from a group of Gaussian graphical models that are themselves dependent. A motivating example is that of modelling gene expression collected on multiple tissues from the same individual: here the multivariate outcome is affected by dependencies acting not only at the level of the specific tissues, but also at the level of the whole...
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作者:Chiou, Jeng-Min; Mueller, Hans-Georg
作者单位:Academia Sinica - Taiwan; University of California System; University of California Davis
摘要:Functional data vectors consisting of samples of multivariate data where each component is a random function are encountered increasingly often but have not yet been comprehensively investigated. We introduce a simple pairwise interaction model that leads to an interpretable and straightforward decomposition of multivariate functional data and of their variation into component-specific processes and pairwise interaction processes. The latter quantify the degree of pairwise interactions between...
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作者:George, E. Olusegun; Cheon, Kyeongmi; Yuan, Yilian; Szabo, Aniko
作者单位:University of Memphis; Merck & Company; Medical College of Wisconsin
摘要:We derive an expression for the joint distribution of exchangeable multinomial random variables, which generalizes the multinomial distribution based on independent trials while retaining some of its important properties. Unlike de Finneti's representation theorem for a binary sequence, the exchangeable multinomial distribution derived here does not require that the finite set of random variables under consideration be a subset of an infinite sequence. Using expressions for higher moments and ...
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作者:Ettinger, B.; Perotto, S.; Sangalli, L. M.
作者单位:Emory University; Polytechnic University of Milan
摘要:We propose a regression model for data spatially distributed over general two-dimensional Riemannian manifolds. This is a generalized additive model with a roughness penalty term involving a differential operator computed over the non-planar domain. By virtue of a semiparametric framework, the model allows inclusion of space-varying covariate information. Estimation can be performed by conformally parameterizing the non-planar domain and then generalizing existing models for penalized spatial ...