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作者：Ng, ETM; Cook, RJ
作者单位：University of Waterloo
摘要：Tests of homogeneity are being increasingly used for the analysis of event time data, but relatively little attention has been paid to their distributional properties in settings with small to moderate sample sizes. Here: we consider tests of homogeneity for recurrent event data in which the null model is a Poisson process and the alternative is a mixed Poisson process. We examine score and adjusted score statistics in the contest of parametric and semiparametric regression models, where the a...
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作者：Yang, S; Prentice, RL
作者单位：Texas Tech University System; Texas Tech University; Fred Hutchinson Cancer Center
摘要：For fitting the proportional odds regression model with right-censored survival times, we introduce some weighted empirical odds functions. These functions are solutions of some self-consistency equations and have a nice martingale representation. From these functions, several classes of new regression estimators, such as the pseudo-maximum likelihood estimator, martingale residual-based estimators, and minimum distance estimators, are derived. These estimators have desirable properties such a...
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作者：Gijbels, I; Mammen, E; Park, BU; Simar, L
作者单位：Universite Catholique Louvain; Ruprecht Karls University Heidelberg; Seoul National University (SNU); Universite Catholique Louvain; Universite Catholique Louvain
摘要：When analyzing the productivity of firms, one may want to compare how the firms transform a set of inputs I (typically labor, energy or capital) into an output y (typically a quantity of goods produced). The economic efficiency of a firm is then defined in terms of its ability to operate close to or on the production frontier, the boundary of the production set. The Frontier function gives the maximal level of output attainable by a firm for a given combination of its inputs. The efficiency of...
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作者：Lahiri, SN; Kaiser, MS; Cressie, N; Hsu, NJ
作者单位：Iowa State University; Tunghai University
摘要：The spatial cumulative distribution function (SCDF) is a random function that provides a statistical summary of a random field over a spatial domain of interest. In this article we develop a spatial subsampling method fur predicting an SCDF based on observations made on a hexagonal grid, similar to the one used in the Environmental Monitoring and Assessment Program of the U.S. Environmental Protection Agency. We show that under quite general conditions, the proposed subsampling method provides...
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作者：Liu, JS; Neuwald, AF; Lawrence, CE
作者单位：Stanford University; Cold Spring Harbor Laboratory; State University of New York (SUNY) System; Wadsworth Center
摘要：The alignment of multiple homologous biopolymer sequences is crucial in research on protein modeling and engineering, molecular evolution, and prediction in terms of both gene function and gene product structure. In this article we provide a coherent view of the two recent models used for multiple sequence alignment-the hidden Markov model (HMM) and the block-based motif model-to develop a set of new algorithms that have both the sensitivity of the block-based model and the flexibility of the ...
