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作者：Wei, Ying
作者单位：Columbia University
摘要：Multivariate quantile contours are useful in numerous applications and have been studied in different contexts. However, no easy solutions exist when dynamic and conditional quantile contours are needed without strong distributional assumptions. In this article we propose a new form of bivariate quantile contours and a two-stage estimation procedure to take time effect into account. The proposed procedure relies on quantile regression for longitudinal data and is flexible to include potentiall...
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作者：Chiou, Jeng-Min; Li, Pai-Ling
作者单位：Tamkang University
摘要：A correlation-based functional clustering method is proposed for grouping curves with similar shapes. A correlation between two random functions defined through the functional inner product is used as a similarity measure. Curves with similar shapes are embedded in the cluster subspace spanned by a a mean shape function and eigenfunctions of the covariance kernel. The cluster membership prediction for each curve attempts to maximize the functional correlation between the observed and predicted...
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作者：O'Malley, A. James; Zaslavsky, Alan M.
作者单位：Harvard University; Harvard Medical School
摘要：Health care quality surveys in the United States are administered to individual respondents (i.e.. hospital patients, health plan members) to evaluate the performance of health care organizations (i.e., hospitals, health plans). which thus Constitute estimation domains. For better understanding and more parsimonious reporting of dimensions of quality, we analyze relationships among., quality Measures at the domain level. Rather than specifying a full parametric model for the observed responses...
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作者：Gillen, Daniel L.; Johnson, Wesley O.
作者单位：University of California System; University of California Irvine
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作者：MacEachern, Steven N.
作者单位：University System of Ohio; Ohio State University
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作者：Manuel Pavia, Jose; Larraz, Beatriz; Maria Montero, Jose
作者单位：University of Valencia; Universidad de Castilla-La Mancha
摘要：There exists a large literature on the problem of forecasting election results. But none of the published methods take spatial information into account, although there is clear evidence of geographic trends. To fill this gap, we use geostatical procedures to build a spatial model of voting patterns. We test the model in three close elections and find that it outperforms rival methods in current use. We apply kriging (a spatial model) and cokriging (in a spatiotemporal model version) to improve...
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作者：Li, Gang; Zhou, Kefei
作者单位：University of California System; University of California Los Angeles; Perrigo Company PLC; Perrigo Company PLC North America
摘要：We present a unified approach to nonparametric comparisons of receiver operating characteristic (ROC) curves for a paired design with clustered data. Treating empirical ROC curves as stochastic processes, their asymptotic joint distribution is derived in the presence of both between-marker and within-subject correlations. A Monte Carlo method is developed to approximate their joint distribution without involving nonparametric density estimation. The developed theory is applied to derive new in...
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作者：Ma, Yanyuan; Yin, Guosheng
作者单位：University of Neuchatel; University of Texas System; UTMD Anderson Cancer Center
摘要：Cure rate models explicitly account for the survival fraction in failure time data. When the covariates are measured with errors, naively treating mismeasured covariates as error-free would cause estimation bias and thus lead to incorrect inference. Under the proportional hazards cure model, we propose a corrected score approach as well as its generalization, and implement a transformation on the mismeasured covariates toward error additivity and/or normality. The corrected score equations can...
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作者：Dunson, David B.; Herring, Amy H.; Siega-Riz, Anna Maria
作者单位：Duke University; 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：In epidemiology, it often is of interest to assess how individuals with different trajectories over time in an environmental exposure or biomarker differ with respect to a continuous response. For ease in interpretation and presentation of results. epidemiologists typically categorize predictors before analysis. To extend this approach to time-varying predictors, individuals can be clustered by then predictor trajectory, with the cluster index included as a predictor in a regression model for ...
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作者：Gao, Jiti; Gijbels, Irene
作者单位：University of Adelaide; Universite Catholique Louvain
摘要：We propose a sound approach to bandwidth selection in nonparametric kernel testing. The main idea is to find an Edgeworth expansion of the asymptotic distribution of the test concerned Due to the involvement of a kernel bandwidth in the leading term of the Edgeworth expansion. we dire able to establish closed-form expressions to explicitly represent the leading terms of both the size and power functions and then determine how the bandwidth should be chosen according to certain requirements for...
