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作者：Guan, Yongtao
作者单位：Yale University
摘要：We introduce new variance estimation procedures for second-order statistics that are computed from a single realization of intensity reweighted stationary spatial point processes. The statistics are defined either on a subset B of the observation window or on the whole window. For the former, we use subblocks that have the same size and shape as B as replicates of B in order to estimate the target variance. For the latter, we develop a subsampling estimator for a key component in the target va...
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作者：Scharpf, Robert B.; Tjelmeland, Hakon; Parmigiani, Giovanni; Nobel, Andrew B.
作者单位：Norwegian University of Science & Technology (NTNU); Johns Hopkins University; Johns Hopkins Bloomberg School of Public Health; Johns Hopkins University; Johns Hopkins Medicine; University of North Carolina; University of North Carolina Chapel Hill
摘要：In this article we define a hierarchical Bayesian model for microarray expression data collected from several studies and use it to identify genes that show differential expression between two conditions. Key features include shrinkage across both gene.; and studies, and flexible modeling that allows for interactions between platforms and the estimated effect, as well as concordant and discordant differential expression across studies. We evaluate the performance of our model in a comprehensiv...
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作者：Peng, Jie; Wang, Pei; Zhou, Nengfeng; Zhu, Ji
作者单位：University of California System; University of California Davis; Fred Hutchinson Cancer Center; University of Michigan System; University of Michigan
摘要：In this article, we propose a computationally efficient approach-space (Sparse PArtial Correlation Estimation)-for selecting nonzero partial correlations under the high-dimension-low-sample-size setting. This method assumes the overall sparsity of the partial correlation matrix and employs sparse regression techniques for model fitting. We illustrate the performance of space by extensive simulation studies. It is shown that space performs well in both nonzero partial correlation selection and ...
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作者：Liu, Yi; Hsu, Jason
作者单位：University System of Ohio; Ohio State University
摘要：Testing for efficacy in multiple endpoints has emerged as an important statistical problem. The Food and Drug Administration (FDA) will issue a guidance on Multiple Endpoints in the near future. When there are primary and secondary endpoints, efficacy in the secondary endpoint is relevant only if efficacy in the primary endpoint has been shown. Thus, there are defined paths to decision making. Current approaches to this problem are based on closed testing, testing all possible intersection hyp...
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作者：Cheng, Yu-Jen; Crainiceanu, Ciprian M.
作者单位：Johns Hopkins University
摘要：We propose, develop, and implement a fully Bayesian inferential approach for the Cox model when the log hazard function contains unknown smooth functions of the variables measured with error. Our approach is to model nonparametrically both the log-baseline hazard and the smooth components of the log-hazard functions using low-rank penalized splines. Careful implementation of the Bayesian inferential machinery is shown to produce remarkably better results than the naive approach. Our methodolog...
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作者：Schafer, Chad M.; Stark, Philip B.
作者单位：Carnegie Mellon University; University of California System; University of California Berkeley
摘要：This article presents a Monte Carlo method for approximating the minimax expected size (MES) confidence set for a parameter known to lie in a compact set. The algorithm is motivated by problems in the physical sciences in which parameters are unknown physical constants related to the distribution of observable phenomena through complex numerical models. The method repeatedly draws parameters at random from the parameter space and simulates data as if each of those values were the true value of...
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作者：Cai, Zongwu; Xu, Xiaoping
作者单位：University of North Carolina; University of North Carolina Charlotte; Xiamen University; China University of Geosciences
摘要：In this article, quatile regression in methods are suggested for a class of smooth coefficient time series models. We use both local polynomial and local constant fitting schemes to estimate the smooth coefficients in a quantile framework. We establish the asymptotic propel-ties of both the local polynomial and local constant estimators For alpha-mixing time series. Also, a bandwidth selector based on the nonparametric version of the Akaike information criterion is sugggested. together with a ...
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作者：Posch, Martin; Zehetmayer, Sonja; Bauer, Peter
作者单位：Medical University of Vienna
摘要：When testing a single hypothesis. it is common knowledge that increasing the sample size after nonsignificant results and repeating the hypothesis test several times at unadjusted critical levels inflates tire overall Type I error rate severely. In contrast, if a large number of hypotheses are tested controlling the False Discovery Rate, such hunting for significance has asymptotically no impact on the error rate. More specifically. if the sample size is increased for all hypotheses simultaneo...
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作者：Xie, Minge; Singh, Kesar; Zhang, Cun-Hui
作者单位：Rutgers University System; Rutgers University New Brunswick
摘要：Frequentist confidence intervals for population ranks and their statistical justifications;ire not well established. even though here is a great need for such procedures in a practice. How do we assign confidence bounds for the ranks of health care facilities, school, and financial institution based on data that do not clearly separate the performance of different entities apart? The commonly used bootstrap-based frequentist confidence intervals and Bayesian intervals for population ranks may ...
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作者：Moodie, Erica E. M.; Platt, Robert W.; Kramer, Michael S.
作者单位：McGill University; McGill University; McGill University; McGill University
摘要：To estimate the sequence of actions that optimizes response in a longitudinal setting, it is important to study the actions as part of a set of decision rules rather than in a series of single-action comparisons. We take as our motivating example the estimation of the set of decision rules for the duration of breastfeeding with a view to maximizing infant growth. Breastfeeding has many well-recognized beneficial effects on health and development. However observational evidence has suggested th...
