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作者：Braun, TM; Feng, ZD
作者单位：University of Michigan System; University of Michigan; Fred Hutchinson Cancer Center
摘要：Two facts complicate the comparison of interventions in group randomized trials (GRT's), a family of clinical trials in which each member of a particular group receives the same treatment assignment. First, individual outcomes within each group are often correlated. Second, the number of groups in a GRT is often not sufficient to make asymptotic approximations possible. Therefore, the tests used with methods, such as generalized estimating equations (GEE) and penalized quasi likelihood (PQL), ...
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作者：Quinn, TJ II; Mizroch, SA
作者单位：University of Alaska System; University of Alaska Fairbanks; National Oceanic Atmospheric Admin (NOAA) - USA
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作者：Peel, D; Whiten, WJ; McLachlan, GJ
作者单位：University of Queensland
摘要：When examining a rock mass, joint sets and their orientations can play a significant role with regard to how the rock mass will behave. To identify joint sets present in the rock mass, the orientation of individual fracture planer can be measured on exposed rock faces and the resulting data can be examined for heterogeneity. In this article, the expectation-maximization algorithm is used to lit mixtures of Kent component distributions to the fracture data to aid in the identification of joint ...
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作者：Klaassen, FJGM; Magnus, JR
作者单位：University of Amsterdam; Tilburg University
摘要：This article tests whether points in tennis are independent and identically distributed (iid). We model the probability of winning a point on service and show that points are neither independent nor identically distributed: winning the previous point has a positive effect on winning the current point, and at important points it is more difficult for the server to win the point than at less important points. Furthermore, the weaker a player, the stronger are these effects. Deviations from lid a...
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作者：Ishwaran, H; James, LF
作者单位：Cleveland Clinic Foundation; Johns Hopkins University
摘要：A rich and flexible class of random probability measures, which we call stick-breaking pliers, can be constructed using a sequence of independent beta random variables. Examples of random measures that have this characterization include the Dirichlet process, its two-parameter extension, the two-parameter Poisson-Dirichlet process, finite dimensional Dirichlet priors, and beta two-parameter processes. The rich nature of stick-breaking priors offers Bayesians a useful class of priors for nonpar...
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作者：Antoniadis, A; Fan, JQ
作者单位：Communaute Universite Grenoble Alpes; Universite Grenoble Alpes (UGA); Chinese University of Hong Kong
摘要：In this paper, we introduce nonlinear regularized wavelet estimators for estimating nonparametric regression functions when sampling points are not uniformly spaced. The approach can apply readily to many other statistical contexts. Various new penalty functions are proposed. The hard-thresholding and soft-thresholding estimators of Donoho and Johnstone are specific members of nonlinear regularized wavelet estimators. They correspond to the lower and upper envelopes of a class of the penalized...
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作者：Lin, DY; Ying, Z
作者单位：University of North Carolina; University of North Carolina Chapel Hill; Columbia University
摘要：This article deals with the regression analysis of repeated measurements taken at irregular and possibly subject-specific time points. The proposed semiparametric and nonparametric models postulate that the marginal distribution for the repeatedly measured response variable Y at time t is related to the vector of possibly time-varying covariates X through the equations E{Y(t)\X(t)} = alpha (0)(t) + beta'X-0(t) and E{Y(t)\X(t)\} = alpha (0)(t) + beta'(0)(t)X(t), where alpha (0)(t) is an arbitra...
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作者：Müller, P; Rosner, GL; Inoue, LYT; Dewhirst, MW
作者单位：Duke University; University of Texas System; UTMD Anderson Cancer Center; Duke University
摘要：We propose a model for longitudinal data with random effects that includes model-based smoothing of measurements over time. This research is motivated by experiments evaluating the hemodynamic effects of various agents in tumor-bearing rats. In one set of experiments, the rats breathed room air, followed by carbogen (a mixture of pure oxygen and carbon dioxide). The experimental responses are longitudinal measurements of oxygen pressure measured in tissue, tumor blood flow, and mean arterial p...
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作者：Morris, JS; Wang, NY; Lupton, JR; Chapkin, RS; Turner, ND; Hong, MY; Carroll, RJ
作者单位：University of Texas System; UTMD Anderson Cancer Center; Texas A&M University System; Texas A&M University College Station; Texas A&M University System; Texas A&M University College Station; Texas A&M University System; Texas A&M University College Station
摘要：An important problem in studying the etiology of colon cancer is understanding the relationship between DNA adduct levels (broadly, DNA damage) in cells within colonic crypts in distal and proximal parts of the colon, following treatment with a carcinogen and different types of diet. In particular, it is important to understand whether rats who have elevated adduct levels in particular positions in distal region crypts also have elevated levels in the same positions of the crypts in proximal r...
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作者：Yee, TW; Wild, CJ
作者单位：University of Auckland
