2015

最新文章

• Testing differential networks with applications to the detection of gene-gene interactions AI翻译
  作者：Xia, Yin; Cai, Tianxi; Cai, T. Tony
  作者单位：University of North Carolina; University of North Carolina Chapel Hill; Harvard University; Harvard T.H. Chan School of Public Health; University of Pennsylvania
  摘要：Model organisms and human studies have yielded increasing empirical evidence that interactions among genes contribute broadly to genetic variation of complex traits. In the presence of gene-gene interactions, the dimensionality of the feature space becomes extremely high relative to the sample size. This poses a significant methodological challenge in the identification of gene-gene interactions. In this paper, by using a Gaussian graphical model framework, we translate the problem of identify...
• On the occurrence times of componentwise maxima and bias in likelihood inference for multivariate max-stable distributions AI翻译
  作者：Wadsworth, Jennifer L.
  作者单位：Lancaster University
  摘要：Full likelihood-based inference for high-dimensional multivariate extreme value distributions, or max-stable processes, is feasible when incorporating occurrence times of the maxima; without this information, d-dimensional likelihood inference is usually precluded due to the large number of terms in the likelihood. However, some studies have noted bias when performing high-dimensional inference that incorporates such event information, particularly when dependence is weak. We elucidate this ph...
• Automatic structure recovery for additive models AI翻译
  作者：Wu, Yichao; Stefanski, Leonard A.
  作者单位：North Carolina State University
  摘要：We propose an automatic structure recovery method for additive models, based on a backfitting algorithm coupled with local polynomial smoothing, in conjunction with a new kernel-based variable selection strategy. Our method produces estimates of the set of noise predictors, the sets of predictors that contribute polynomially at different degrees up to a specified degree M, and the set of predictors that contribute beyond polynomially of degree M. We prove consistency of the proposed method, an...
• General weighted optimality of designed experiments AI翻译
  作者：Stallings, J. W.; Morgan, J. P.
  作者单位：North Carolina State University; Virginia Polytechnic Institute & State University
  摘要：The standard approach to finding optimal experimental designs employs conventional measures of design efficacy, such as the A, E, and D-criterion, that assume equal interest in all estimable functions of model parameters. This paper develops a general theory for weighted optimality, allowing precise design selection according to expressed relative interest in different functions in the estimation space. The approach employs a very general class of matrix-specified weighting schemes that produc...
• Consistent testing for recurrent genomic aberrations AI翻译
  作者：Walter, V.; Wright, F. A.; Nobel, A. B.
  作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Penn State Health; North Carolina State University; University of North Carolina; University of North Carolina Chapel Hill
  摘要：We consider the detection and identification of recurrent departures from stationary behaviour in genomic or similarly arranged data containing measurements at an ordered set of variables. Our primary focus is on departures that occur only at a single variable, or within a small window of contiguous variables, but involve more than one sample. This encompasses the identification of aberrant markers in genome-wide measurements of DNA copy number and DNA methylation, as well as meta-analyses of ...
• Direct estimation of the mean outcome on treatment when treatment assignment and discontinuation compete AI翻译
  作者：Lu, Xin; Johnson, Brent A.
  作者单位：Emory University; Rollins School Public Health; University of Rochester
  摘要：Several authors have investigated the challenges of statistical analyses and inference in the presence of early treatment termination, including a loss of efficiency in randomized controlled trials and a connection to dynamic regimes in observational studies. Popular estimation strategies for causal estimands in dynamic regimes lend themselves to studies where treatment is assigned at a finite number of points and the extension to continuous treatment assignment is nontrivial. We re-examine th...
• Diagnostic studies in sufficient dimension reduction AI翻译
  作者：Chen, Xin; Cook, R. Dennis; Zou, Changliang
  作者单位：National University of Singapore; University of Minnesota System; University of Minnesota Twin Cities; Nankai University
  摘要：Sufficient dimension reduction in regression aims to reduce the predictor dimension by replacing the original predictors with some set of linear combinations of them without loss of information. Numerous dimension reduction methods have been developed based on this paradigm. However, little effort has been devoted to diagnostic studies within the context of dimension reduction. In this paper we introduce methods to check goodness-of-fit for a given dimension reduction subspace. The key idea is...
• Benchmarked empirical Bayes methods in multiplicative area-level models with risk evaluation AI翻译
  作者：Ghosh, M.; Kubokawa, T.; Kawakubo, Y.
  作者单位：State University System of Florida; University of Florida; University of Tokyo; University of Tokyo
  摘要：The paper develops hierarchical empirical Bayes and benchmarked hierarchical empirical Bayes estimators of positive small area means under multiplicative models. The usual benchmarking requirement is that the small area estimates, when aggregated, should equal the direct estimates for the larger geographical areas. However, while estimating positive small area parameters, the conventional squared error or weighted squared error loss subject to the usual benchmark constraint may not produce pos...
• Maximum projection designs for computer experiments AI翻译
  作者：Joseph, V. Roshan; Gul, Evren; Ba, Shan
  作者单位：University System of Georgia; Georgia Institute of Technology; Procter & Gamble
  摘要：Space-filling properties are important in designing computer experiments. The traditional maximin and minimax distance designs consider only space-filling in the full-dimensional space; this can result in poor projections onto lower-dimensional spaces, which is undesirable when only a few factors are active. Restricting maximin distance design to the class of Latin hypercubes can improve one-dimensional projections but cannot guarantee good space-filling properties in larger subspaces. We prop...
• Adaptive randomized trial designs that cannot be dominated by any standard design at the same total sample size AI翻译
  作者：Rosenblum, Michael
  作者单位：Johns Hopkins University; Johns Hopkins Bloomberg School of Public Health
  摘要：Prior work has shown that the power of adaptive designs with rules for modifying the sample size can always be matched or improved by suitably chosen, standard, group sequential designs. A natural question is whether analogous results hold for other types of adaptive designs. We focus on adaptive enrichment designs, which involve preplanned rules for modifying enrollment criteria based on accrued data in a randomized trial. Such designs often involve multiple hypotheses, e.g., one for the tota...