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作者：Ren, Boyu; Bacallado, Sergio; Favaro, Stefano; Holmes, Susan; Trippa, Lorenzo
作者单位：Harvard University; University of Cambridge; University of Turin; Stanford University
摘要：Human microbiome studies use sequencing technologies to measure the abundance of bacterial species or Operational Taxonomic Units (OTUs) in samples of biological material. Typically the data are organized in contingency tables with OTU counts across heterogeneous biological samples. In the microbial ecology community, ordination methods are frequently used to investigate latent factors or clusters that capture and describe variations of OTU counts across biological samples. It remains importan...
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作者：Tu, Wanzhu
作者单位：Indiana University System; Indiana University Bloomington
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作者：Zhou, Yong-Dao; Xu, Hongquan
作者单位：Sichuan University; University of California System; University of California Los Angeles
摘要：Central composite designs are widely used in practice for factor screening and building response surface models. We study two classes of newcomposite designs. The first class consists of a two-level factorial design and a three-level orthogonal array; the second consists of a two-level factorial and a three-level definitive screening design. We derive bounds of their efficiencies for estimating all and part of the parameters in a second-order model and obtain some general theoretical results. ...
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作者：Blackwell, Matthew
作者单位：Harvard University
摘要：In democratic countries, voting is one of the most important ways forcitizens to influence policy and hold their representatives accountable. And yet, in the United States and many other countries, rates of Voter turnout are alarmingly low. Every election cycle, mobilization efforts encourage citizens to vote and ensure that elections reflect the true will of the people. To establish the most effective way of encouraging voter turnout, this article seeks to differentiate between (1) the synerg...
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作者：Fan, Ailin; Song, Rui; Lu, Wenbin
作者单位：North Carolina State University
摘要：We propose a systematic method for testing and identifying a subgroup with an enhanced treatment effect. We adopts a change-plane technique to first test the existence of a subgroup, and then identify the subgroup if the null hypothesis on nonexistence of such a subgroup is rejected. A semiparametric model is considered for the response with an unspecified baseline function and an interaction between a subgroup indicator and treatment. A doubly robust test statistic is constructed based on thi...
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作者：Ma, Shujie; Li, Runze; Tsai, Chih-Ling
作者单位：University of California System; University of California Riverside; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; University of California System; University of California Davis
摘要：In quantile linear regression with ultrahigh-dimensional data, we propose an algorithm for screening all candidate variables and subsequently selecting relevant predictors. Specifically, we first employ quantile partial correlation for screening, and then we apply the extended Bayesian information criterion (EBIC) for best subset selection. Our proposed method can successfully select predictors when the variables are highly correlated, and it can also identify variables that make a contributio...
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作者：He, Xu
作者单位：Chinese Academy of Sciences; Academy of Mathematics & System Sciences, CAS
摘要：We propose a new class of space-filling designs called rotated sphere packing designs for computer experiments. The approach starts from the asymptotically optimal positioning of identical balls that covers the unit cube. Properly scaled, rotated, translated, and extracted, such designs are excellent in maximin distance criterion, low in discrepancy, good in projective uniformity and thus useful in both prediction and numerical integration purposes. We provide a fast algorithm to construct suc...
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作者：Huang, Yuan; Zhang, Qingzhao; Zhang, Sanguo; Huang, Jian; Ma, Shuangge
作者单位：Yale University; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS
摘要：For data with high-dimensional covariates but small sample sizes, the analysis of single datasets often generates unsatisfactory results. The integrative analysis of multiple independent datasets provides an effective way of pooling information and outperforms single-dataset and several alternative multi-datasets methods. Under many scenarios, multiple datasets are expected to share common important covariates, that is, the corresponding models have similarity in their sparsity structures. How...
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作者：Hui, Francis K. C.; Mueller, Samuel; Welsh, A. H.
作者单位：Australian National University; University of Sydney
摘要：The application of generalized linear mixed models presents some major challenges for both estimation, due to the intractable marginal likelihood, and model selection, as we usually want to jointly select over both fixed and random effects. We propose to overcome these challenges by combining penalized quasi-likelihood (PQL) estimation with sparsity inducing penalties on the fixed and random coefficients. The resulting approach, referred to as regularized PQL, is a computationally efficient me...
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作者：Schennach, Susanne M.; Wilhelm, Daniel
作者单位：Brown University; University of London; University College London
摘要：We propose a simple model selection test for choosing among two parametric likelihoods, which can be applied in the most general setting without any assumptions on the relation between the candidate models and the true distribution. That is, both, one or neither is allowed to be correctly specified or misspecified, they may be nested, nonnested, strictly nonnested, or overlapping. Unlike in previous testing approaches, no pretesting is needed, since in each case, the same test statistic togeth...
