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作者：Dai, James Y.; Gilbert, Peter B.; Masse, Benoit R.
作者单位：Fred Hutchinson Cancer Center; Universite de Montreal
摘要：It is frequently of interest to estimate the intervention effect that adjusts for post-randomization variables in clinical trials. In the recently completed HPTN 035 trial, there is differential condom use between the three microbicide gel arms and the no-gel control arm, so intention-to-treat (ITT) analyses only assess the net treatment effect that includes the indirect treatment effect mediated through differential condom use. Various statistical methods in causal inference have been develop...
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作者：Wiesenfarth, Manuel; Krivobokova, Tatyana; Klasen, Stephan; Sperlich, Stefan
作者单位：University of Gottingen; University of Gottingen; University of Gottingen; University of Gottingen; University of Geneva
摘要：This article proposes a simple and fast approach to build simultaneous confidence bands and perform specification tests for smooth curves in additive models. The method allows for handling of spatially heterogeneous functions and its derivatives as well as heteroscedasticity in the data. It is applied to study the determinants of chronic undernutrition of Kenyan children, with a particular focus on the highly nonlinear age pattern in undernutrition. Model estimation using the mixed model repre...
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作者：Fan, Jianqing; Han, Xu; Gu, Weijie
作者单位：Princeton University; Shanghai University of Finance & Economics; Pennsylvania Commonwealth System of Higher Education (PCSHE); Temple University
摘要：Multiple hypothesis testing is a fundamental problem in high-dimensional inference, with wide applications in many scientific fields. In genome-wide association studies, tens of thousands of tests are performed simultaneously to find if any single-nucleotide polymorphisms (SNPs) are associated with some traits and those tests are correlated. When test statistics are correlated, false discovery control becomes very challenging under arbitrary dependence. In this article, we propose a novel meth...
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作者：Huang, Mian; Yao, Weixin
作者单位：Shanghai University of Finance & Economics; Kansas State University
摘要：In this article, we study a class of semiparametric mixtures of regression models, in which the regression functions are linear functions of the predictors, but the mixing proportions are smoothing functions of a covariate. We propose a one-step backfitting estimation procedure to achieve the optimal convergence rates for both regression parameters and the nonparametric functions of mixing proportions. We derive the asymptotic bias and variance of the one-step estimate, and further establish i...
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作者：Bondell, Howard D.; Reich, Brian J.
作者单位：North Carolina State University
摘要：For high-dimensional data, particularly when the number of predictors greatly exceeds the sample size, selection of relevant predictors for regression is a challenging problem. Methods such as sure screening, forward selection, or penalized regressions are commonly used. Bayesian variable selection methods place prior distributions on the parameters along with a prior over model space, or equivalently, a mixture prior on the parameters having mass at zero. Since exhaustive enumeration is not f...
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作者：Bhattacharya, Anirban; Dunson, David B.
作者单位：Duke University
摘要：Gaussian latent factor models are routinely used for modeling of dependence in continuous, binary, and ordered categorical data. For unordered categorical variables, Gaussian latent factor models lead to challenging computation and complex modeling structures. As an alternative, we propose a novel class of simplex factor models. In the single-factor case, the model treats the different categorical outcomes as independent with unknown marginals. The model can characterize flexible dependence st...
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作者：Ba, Shan; Joseph, V. Roshan
作者单位：University System of Georgia; Georgia Institute of Technology
摘要：Space-filling designs such as Latin hypercube designs (LHDs) are widely used in computer experiments. However, finding an optimal LHD with good space-filling properties is computationally cumbersome. On the other hand, the well-established factorial designs in physical experiments are unsuitable for computer experiments owing to the redundancy of design points when projected onto a subset of factor space. In this work, we present a new class of space-filling designs developed by splitting two-...
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作者：Kraemer, Nicole; Sugiyama, Masashi
作者单位：Leibniz Association; Weierstrass Institute for Applied Analysis & Stochastics; Institute of Science Tokyo; Tokyo Institute of Technology
摘要：The derivation of statistical properties for partial least squares regression can be a challenging task. The reason is that the construction of latent components from the predictor variables also depends on the response variable. While this typically leads to good performance and interpretable models in practice, it makes the statistical analysis more involved. In this work, we study the intrinsic complexity of partial least squares regression. Our contribution is an unbiased estimate of its d...
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作者：Polonik, Wolfgang
作者单位：University of California System; University of California Davis
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作者：Finley, Andrew O.; Banerjee, Sudipto; MacFarlane, David W.
作者单位：Michigan State University; Michigan State University; University of Minnesota System; University of Minnesota Twin Cities
摘要：We are interested in predicting one or more continuous forest variables (e.g., biomass, volume, age) at a fine resolution (e.g., pixel level) across a specified domain. Given a definition of forest/nonforest, this prediction is typically a two-step process. The first step predicts which locations are forested. The second step predicts the value of the variable for only those forested locations. Rarely is the forest/nonforest status predicted without error. However, the uncertainty in this pred...
