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作者：Yu, Menggang; Taylor, Jeremy M. G.; Sandler, Howard M.
作者单位：Indiana University System; Indiana University Indianapolis; University of Michigan System; University of Michigan; University of Michigan System; University of Michigan
摘要：Patients treated for prostate cancer are monitored by periodically measuring prostate-specific antigen (PSA) after treatment. Increases in PSA are suggestive of cancer recurrence and are used in making decisions about possible new treatments. The data from studies of such patients typically consist of longitudinal PSA measurements, censored event times, and baseline covariates. Methods for the combined analysis of both longitudinal and survival data have been developed in recent years, with th...
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作者：Dunson, David B.; Xue, Ya; Carin, Lawrence
作者单位：National Institutes of Health (NIH) - USA; NIH National Institute of Environmental Health Sciences (NIEHS); General Electric; Duke University
摘要：In analyzing data from multiple related studies, it often is of interest to borrow information across studies and to cluster similar studies. Although parametric hierarchical models are commonly used, of concern is sensitivity to the form chosen for the random-effects distribution. A Dirichlet process (DP) prior can allow the distribution to be unknown, while clustering studies; however, the DP does not allow local clustering of studies with respect to a subset of the coefficients without maki...
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作者：van Soest, Arthur; Hurd, Michael
作者单位：RAND Corporation; Tilburg University
摘要：We analyze experimental survey data, with a random split into respondents who get an open-ended question on the amount of total family consumption (with follow-up unfolding brackets of the form Is consumption $X or more? for those who answer don't know or refuse) and respondents who are immediately directed to unfolding brackets. In both cases, the entry point of the unfolding bracket sequence is randomized. Allowing for any type of selection into answering the open-ended or bracket questions,...
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作者：Crainiceanu, Ciprian M.; Diggle, Peter J.; Rowlingson, Barry
作者单位：Johns Hopkins University; Lancaster University; Lancaster University
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作者：Zabell, S. L.
作者单位：Northwestern University; Northwestern University
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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：Diaconis, Persi; Lehmann, Erich
作者单位：Stanford University; University of California System; University of California Berkeley
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作者：Delaigle, Aurore; Hall, Peter
作者单位：University of Bristol; University of Melbourne
摘要：SIMEX methods are attractive for solving curve estimation problems in errors-in-variables regression, using parametric or semiparametric techniques. However, nonparametric approaches are generally of quite a different type, being based on, for example, kernels, local-linear modeling, ridging, orthogonal series, or splines. All of these techniques involve the challenging (and not well studied) issue of empirical smoothing parameter choice. We show that SIMEX can be used effectively for selectin...
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作者：Chen, Jianwei; Wu, Hulin
作者单位：California State University System; San Diego State University; University of Rochester
摘要：Recently deterministic dynamic models have become very popular in biomedical research and other scientific areas; examples include modeling human immunodeficiency virus (HIV) dynamics, pharmacokinetic/pharmacodynamic analysis, tumor cell kinetics, and genetic network modeling. In this article we propose estimation methods for the time-varying coefficients in deterministic dynamic systems that are usually described by a set of differential equations. Three two-stage local polynomial estimators ...
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作者：Hyrien, Ollivier; Zand, Martin S.
作者单位：University of Rochester; University of Rochester
摘要：Recent advances in flow cytometry have resulted in the development of powerful bioassays to analyze the proliferation of cell populations. The carboxy-fluorescein diacetate succinimidyl ester (CFSE)-labeling experiment is one such assay that is widely used to study cell kinetics and as a standard tool for investigating lymphocyte proliferation. Several mathematical models have been proposed to describe cell proliferation during CFSE experiments. The statistical analysis of CFSE-labeling data h...
