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作者：Zeng, Donglin; Lin, D. Y.
作者单位：University of North Carolina; University of North Carolina Chapel Hill
摘要：The accelerated failure time model provides a natural formulation of the effects of covariates on potentially censored response variable. The existing semiparametric estimators are computationally intractable and statistically inefficient. In this article we propose an approximate nonparametric maximum likelihood method for the accelerated failure time model with possibly time-dependent covariates. We estimate the regression parameters by maximizing a kernel-smoothed profile likelihood functio...
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作者：Johnson, Brent A.; Herring, Amy H.; Ibrahim, Joseph G.; Siega-Riz, Anna Maria
作者单位：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：Preterm birth, defined as delivery before 37 completed weeks' gestation, is a leading cause of infant morbidity and mortality. Identifying factors related to preterm delivery is an important goal of public health professionals who wish to identify etiologic pathways to target for prevention. Validation studies are often conducted in nutritional epidemiology in order to study measurement error in instruments that are generally less invasive or less expensive than gold standard instruments. Data...
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作者：Taylor, Jonathan E.; Worsley, Keith J.
作者单位：Stanford University; McGill University
摘要：Brain mapping data have been modeled as Gaussian random fields, and local increases in mean are detected by local maxima of a random field of test statistics derived from these data. Accurate p values for local maxima are readily available for isotropic data based on the expected Euler characteristic of the excursion set of the test statistic random field. In this article we give a simple method for dealing with nonisotropic data. Our approach has connections to the model of Sampson and Guttor...
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作者：Patton, Andrew J.; Timmermann, Allan
作者单位：University of Oxford; University of California System; University of California San Diego
摘要：Empirical tests of forecast optimality have traditionally been conducted under the assumption of mean squared error loss or some other known loss function. In this article we establish new testable properties that hold when the forecaster's loss function is unknown but testable restrictions can be imposed on the data-generating process, trading off conditions on the data-generating process against conditions on the loss function. We propose flexible estimation of the forecaster's loss function...
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作者：Wolpert, Robert L.
作者单位：Duke University
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作者：Cooner, Freda; Banerjee, Sudipto; Carlin, Bradley P.; Sinha, Debajyoti
作者单位：University of Minnesota System; University of Minnesota Twin Cities; Medical University of South Carolina
摘要：With rapid improvements in medical treatment and health care, many datasets dealing with time to relapse or death now reveal a substantial portion of patients who are cured (i.e., who never experience the event). Extended survival models called cure rate models account for the probability of a subject being cured and can be broadly classified into the classical mixture models of Berkson and Gage (BG type) or the stochastic tumor models pioneered by Yakovlev and extended to a hierarchical frame...
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作者：Hoff, Peter D.
作者单位：University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle
摘要：Many multivariate data-analysis techniques for an m x n matrix Y are related to the model Y = M + E, where Y is an m x 17 matrix of full rank and M is an unobserved mean matrix of rank K < (m boolean AND n). Typically the rank of M is estimated in a heuristic way and then the least-squares estimate of M is obtained via the singular value decomposition of Y, yielding an estimate that can have a very high variance. In this article we suggest a model-based alternative to the preceding approach by...
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作者：Keller-McNulty, Sallie
作者单位：Rice University
摘要：Science, engineering, technology, and people-these are the ingredients that must come together to support the growing complexity of today's global challenges, ranging from international security to space exploration. As scientists and engineers, it is essential that we develop the means to put our work into a decision context for policy makers; otherwise, our efforts will only inform the writers of textbooks and not the leaders who shape the world within which we live. Statisticians must step ...
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作者：Bednorz, Witold; Latuszynski, Krzysztof
作者单位：University of Warsaw; Warsaw School of Economics
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作者：Benjamini, Ybav; Heller, Ruth
作者单位：Tel Aviv University; University of Pennsylvania
摘要：The problem of multiple testing for the presence of signal in spatial data can involve numerous locations. Traditionally, each location is tested separately for signal presence, but then the findings are reported in terms of clusters of nearby locations. This is an indication that the units of interest for testing are clusters rather than individual locations. The investigator may know a priori these more natural units or an approximation to them. We suggest testing these cluster units rather ...
