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作者：Hu, Jianhua; Zhu, Hongjian; Hu, Feifang
作者单位：University of Texas System; UTMD Anderson Cancer Center; University of Texas System; University of Texas Health Science Center Houston; University of Texas School Public Health; George Washington University
摘要：Response-adaptive designs have recently attracted more and more attention in the literature because of its advantages in efficiency and medical ethics. To develop personalized medicine, covariate information plays an important role in both design and analysis of clinical trials. A challenge is how to incorporate covariate information in response-adaptive designs while considering issues of both efficiency and medical ethics. To address this problem, we propose a new and unified family of covar...
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作者：Angrist, Joshua D.; Rokkanen, Miikka
作者单位：Massachusetts Institute of Technology (MIT); National Bureau of Economic Research; Columbia University
摘要：In regression discontinuity (RD) studies exploiting an award or admissions cutoff, causal effects are nonparametrically identified for those near the cutoff. The effect of treatment on inframarginal applicants is also of interest, but identification of such effects requires stronger assumptions than those required for identification at the cutoff. This article discusses RD identification and estimation away from the cutoff. Our identification strategy exploits the availability of dependent var...
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作者：Delaigle, Aurore; Zhou, Wen-Xin
作者单位：University of Melbourne; Princeton University
摘要：Group testing is a technique employed in large screening studies involving infectious disease, where individuals in the study are grouped before being observed. Parametric and nonparametric estimators of conditional prevalence have been developed in the group testing literature, in the case where the binary variable indicating the disease status is available only for the group, but the explanatory variable is observed for each individual. However, for reasons such as the high cost of assays, t...
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作者：Chang, Lo-Bin; Geman, Donald
作者单位：University System of Ohio; Ohio State University; Johns Hopkins University
摘要：In recent years, reproducibility has emerged as a key factor in evaluating x applications of statistics to the biomedical sciences, for example, learning predictors of disease phenotypes from high-throughput omics data. In particular, validation is undermined when error rates on newly acquired data are sharply higher than those originally reported. More precisely, when data are collected from m studies representing possibly different subphenotypes, more generally different mixtures of subpheno...
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作者：Sun, Qiang; Zhu, Hongtu; Liu, Yufeng; Ibrahim, Joseph G.
作者单位：University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina; University of North Carolina Chapel Hill
摘要：The aim of this article is to develop a sparse projection regression modeling (SPReM) framework to perform multivariate regression modeling with a large number of responses and a multivariate covariate of interest. We propose two novel heritability ratios to simultaneously perform dimension reduction, response selection, estimation, and testing, while explicitly accounting for correlations among multivariate responses. Our SPReM is devised to specifically address the low statistical power issu...
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作者：Galvao, Antonio F.; Wang, Liang
作者单位：University of Iowa; University of Wisconsin System; University of Wisconsin Milwaukee
摘要：This article studies identification, estimation, and inference of general unconditional treatment effects models with continuous treatment under the ignorability assumption. We show identification of the parameters of interest, the dose-response functions, under the assumption that selection to treatment is based on observables. We propose a semiparametric two-step estimator, and consider estimation of the dose-response functions through moment restriction models with generalized residual func...
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作者：Pedeli, Xanthi; Davison, Anthony C.; Fokianos, Konstantinos
作者单位：Athens University of Economics & Business; Swiss Federal Institutes of Technology Domain; Ecole Polytechnique Federale de Lausanne; University of Cyprus
摘要：Saddlepoint techniques have been used successfully in many applications, owing to the high accuracy with which they can approximate intractable densities and tail probabilities. This article concerns their use for the estimation of high-order integer-valued autoregressive, INAR(p), processes. Conditional least squares estimation and maximum likelihood estimation have been proposed for INAR(p) models, but the first is inefficient for estimating parametric models, and the second becomes difficul...
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作者：Radchenko, Peter; Qiao, Xinghao; James, Gareth M.
作者单位：University of Southern California
摘要：The regression problem involving functional predictors has many important applications and a number of functional regression methods have been developed. However, a common complication in functional data analysis is one of sparsely observed curves, that is predictors that are observed, with error, on a small subset of the possible time points. Such sparsely observed data induce an errors-in-variables model, where one must account for measurement error in the functional predictors. Faced with s...
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作者：Scealy, J. L.; de Caritat, Patrice; Grunsky, Eric C.; Tsagris, Michail T.; Welsh, A. H.
作者单位：Australian National University; Geoscience Australia; Australian National University; Natural Resources Canada; Lands & Minerals Sector - Natural Resources Canada; Geological Survey of Canada; Australian National University
摘要：Geochemical surveys collect sediment or rock samples, measure the concentration of chemical elements, and report these typically either in weight percent or in parts per million (ppm). There are usually a large number of elements measured and the distributions are often skewed, containing many potential outliers. We present a new robust principal component analysis (PCA) method for geochemical survey data, that involves first transforming the compositional data onto a manifold using a relative...
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作者：Chatterjee, A.; Lahiri, S. N.
作者单位：Indian Statistical Institute; Indian Statistical Institute Delhi; North Carolina State University
