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作者：Crainiceanu, Ciprian M.; Staicu, Ana-Maria; Di, Chong-Zhi
作者单位：Johns Hopkins University; North Carolina State University; Fred Hutchinson Cancer Center
摘要：We introduce Generalized Multilevel Functional Linear Models (GMFLMs), a novel statistical framework for regression models where exposure has a multilevel functional structure. We show that GMFLMs are, in fact, generalized multilevel mixed models. Thus, GMFLMs can be analyzed using the mixed effects inferential machinery and can be generalized within a well-researched statistical framework. We propose and compare two methods for inference: (1) a two-stage frequentist approach: and (2) a joint ...
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作者：Xu, Qiang; Paik, Myunghee Cho; Luo, Xiaodong; Tsai, Wei-Yann
作者单位：US Food & Drug Administration (FDA); Columbia University; Icahn School of Medicine at Mount Sinai
摘要：Missingness in covariates is a common problem in survival data. In this article we propose a reweighting method for estimating the regression parameters in the Cox model with missing covariates. We also consider the augmented reweighting method by subtracting the projection term onto the nuisance tangent space. The proposed method provides consistent and asymptotically normally distributed estimators when the missing-data mechanism depends on the outcome variables, its well as on the observed ...
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作者：Gill, Jeff; Casella, George
作者单位：Washington University (WUSTL); State University System of Florida; University of Florida
摘要：A generalized linear mixed model, ordered probit, is used to estimate levels of stress in presidential political appointees as a means of understanding their surprisingly short tenures. A Bayesian approach is developed, where the random effects are modeled with a Dirichlet process mixture prior, allowing for useful incorporation of prior information, but retaining some vagueness in the form of the prior. Applications of Bayesian models in the social sciences are typically done with uninformati...
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作者：Rios Insua, Insua; Rios, Jesus; Banks, David
作者单位：Universidad Rey Juan Carlos; Duke University
摘要：Applications in counterterrorism and corporate competition have led to the development of new methods for the analysis of decision making when there are intelligent opponents and uncertain outcomes. This field represents a combination of statistical risk analysis and game theory, and is sometimes called adversarial risk analysis. In this article, we describe several formulations of adversarial risk problems, and provide a framework that extends traditional risk analysis' tools, such as influen...
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作者：Fryzlewicz, Piotr; Ombao, Hernando
作者单位：University of Bristol; Brown University
摘要：Consider the situation when we have training data containing many time series having known group membership and testing data with unknown group membership. The goals are to find timescale features (using training data) that can best separate the groups, and to use these highly discriminant features to classify test data. We propose a method for classification using a bias-corrected nondecimated wavelet transform. Wavelets are ideal for identifying highly discriminant local time and scale featu...
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作者：Wei, Ying; Carroll, Raymond J.
作者单位：Columbia University; Texas A&M University System; Texas A&M University College Station
摘要：Regression quantiles can be substantially biased when the covariates are measured with error. In this paper we propose a new method that produces consistent linear quantile estimation in the presence of covariate measurement error. The method corrects the measurement error induced bias by constructing joint estimating equations that simultaneously hold for all the quantile levels. An iterative EM-type estimation algorithm to obtain the Solutions to Such joint estimation equations is provided. ...
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作者：O'Sullivan, Finbarr; Muzi, Mark; Spence, Alexander M.; Mankoff, David M.; O'Sullivan, Janet N.; Fitzgerald, Niall; Newman, George C.; Krohn, Kenneth A.
作者单位：University College Cork; University of Washington; University of Washington Seattle; Yeshiva University
摘要：Kinetic analysis is used to extract metabolic information from dynamic positron emission tomography (PET) uptake data. The theory of indicator dilutions, developed in the seminal work of Meier and Zierler (1954), provides a probabilistic framework for representation of PET tracer uptake data in terms of a convolution between an arterial input function and a tissue residue. The residue is a scaled Survival function associated with tracer residence in the tissue. Nonparametric inference for the ...
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作者：Fearnhead, Paul; Vasileiou, Despina
作者单位：Lancaster University
摘要：Statistical identification of isochore structure, the variation in large-scale GC composition (proportion of DNA bases that are G or C as opposed to A or T), of mammalian genomes is a necessary requirement for understanding both the evolution of base composition and the many genomic features such as mutation and recombination rates, which covary with base composition. We have developed a Bayesian method for isochore analysis that we demonstrate to be more accurate than the commonly used binary...
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作者：Carroll, Raymond J.; Delaigle, Aurore; Hall, Peter
作者单位：Texas A&M University System; Texas A&M University College Station; University of Bristol; University of Melbourne; University of California System; University of California Davis
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作者：Einmahl, John H. J.; Li, Jun; Liu, Regina Y.
作者单位：Tilburg University; Tilburg University; University of California System; University of California Riverside; Rutgers University System; Rutgers University New Brunswick
摘要：This article develops a threshold system for monitoring airline performance. This threshold system divides the sample space into regions with increasing levels of risk and allows instant assessments of risk level of any observed airline performance. Of particular concern is the performance with extreme risk. In this article. a multivariate extreme value theory approach is used to establish thresholds for signaling varying levels of extremeness in the context of simultaneous monitoring of multi...
