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作者：Ma, Ling; Hu, Tao; Sun, Jianguo
作者单位：University of Missouri System; University of Missouri Columbia; Capital Normal University
摘要：Current status data occur in contexts including demographic studies and tumorigenicity experiments. In such cases, each subject is observed only once and the failure time of interest is either left- or right-censored (Kalbfleisch & Prentice, 2002). Many methods have been developed for the analysis of such data (Huang, 1996; Sun, 2006), most of which assume that the failure time and the observation time are independent completely or given covariates. In this paper, we present a sieve maximum li...
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作者：Waite, T. W.; Woods, D. C.
作者单位：University of Manchester; University of Southampton
摘要：The selection of optimal designs for generalized linear mixed models is complicated by the fact that the Fisher information matrix, on which most optimality criteria depend, is computationally expensive to evaluate. We provide two novel approximations that reduce the computational cost of evaluating the information matrix by complete enumeration of response outcomes, or Monte Carlo approximations thereof: an asymptotic approximation that is accurate when there is strong dependence between obse...
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作者：Laber, E. B.; Zhao, Y. Q.
作者单位：North Carolina State University; University of Wisconsin System; University of Wisconsin Madison
摘要：Individualized treatment rules recommend treatments on the basis of individual patient characteristics. A high-quality treatment rule can produce better patient outcomes, lower costs and less treatment burden. If a treatment rule learned from data is to be used to inform clinical practice or provide scientific insight, it is crucial that it be interpretable; clinicians may be unwilling to implement models they do not understand, and black-box models may not be useful for guiding future researc...
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作者：Kanamori, Takafumi; Fujisawa, Hironori
作者单位：Nagoya University; Research Organization of Information & Systems (ROIS); Institute of Statistical Mathematics (ISM) - Japan
摘要：Contamination caused by outliers is inevitable in data analysis, and robust statistical methods are often needed. In this paper we develop a new approach for robust data analysis on the basis of scoring rules. A scoring rule is a discrepancy measure to assess the quality of probabilistic forecasts. We propose a simple method of estimating not only parameters in the statistical model but also the contamination ratio, i.e., the ratio of outliers. The outliers are detected based on the estimated ...
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作者：Hui, Francis K. C.; Warton, David I.; Foster, Scott D.
作者单位：University of New South Wales Sydney; Commonwealth Scientific & Industrial Research Organisation (CSIRO)
摘要：Choosing the number of components in a finite mixture model is a challenging task. In this article, we study the behaviour of information criteria for selecting the mixture order, based on either the observed likelihood or the complete likelihood including component labels. We propose a new observed likelihood criterion called aic(mix), which is shown to be order consistent. We further show that when there is a nontrivial level of classification uncertainty in the true model, complete likeliho...
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作者：Nordhausen, Klaus; Tyler, David E.
作者单位：University of Turku; Rutgers University System; Rutgers University New Brunswick
摘要：The sample covariance matrix, which is well known to be highly nonrobust, plays a central role in many classical multivariate statistical methods. A popular way of making such multivariate methods more robust is to replace the sample covariance matrix with some robust scatter matrix. The aim of this paper is to point out that multivariate methods often require that certain properties of the covariance matrix hold also for the robust scatter matrix in order for the corresponding robust plug-in ...
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作者：Cox, D. R.
作者单位：University of Oxford
摘要：So-called big data are likely to have complex structure, in particular implying that estimates of precision obtained by applying standard statistical procedures are likely to be misleading, even if the point estimates of parameters themselves may be reasonably satisfactory. While this possibility is best explored in the context of each special case, here we outline a fairly general representation of the accretion of error in large systems and explore the possible implications for the estimatio...
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作者：Wang, Yuanjia; Liang, Baosheng; Tong, Xingwei; Marder, Karen; Bressman, Susan; Orr-Urtreger, Avi; Giladi, Nir; Zeng, Donglin
作者单位：Beijing Normal University; Columbia University; Harvard University; Harvard University Medical Affiliates; Beth Israel Deaconess Medical Center; Tel Aviv University; Sackler Faculty of Medicine; University of North Carolina; University of North Carolina Chapel Hill
摘要：With the discovery of an increasing number of causal genes for complex human disorders, it is crucial to assess the genetic risk of disease onset for individuals who are carriers of these causal mutations and to compare the distribution of the age-at-onset for such individuals with the distribution for noncarriers. In many genetic epidemiological studies that aim to estimate causal gene effect on disease, the age-at-onset of disease is subject to censoring. In addition, the mutation carrier or...
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作者：Chen, Hua Yun
作者单位：University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital
摘要：This paper points out an error in Davidov and Iliopoulos's (Biometrika 100, 778-80) proof of convergence of an iterative algorithm for the proportional likelihood ratio model. It is shown that the iterative algorithm increases the likelihood in each iteration and converges under mild additional conditions when the odds ratio function is bounded.
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作者：Ma, Ping; Huang, Jianhua Z.; Zhang, Nan
作者单位：University System of Georgia; University of Georgia; Texas A&M University System; Texas A&M University College Station
摘要：Smoothing splines provide flexible nonparametric regression estimators. However, the high computational cost of smoothing splines for large datasets has hindered their wide application. In this article, we develop a new method, named adaptive basis sampling, for efficient computation of smoothing splines in super-large samples. Except for the univariate case where the Reinsch algorithm is applicable, a smoothing spline for a regression problem with sample size n can be expressed as a linear co...
