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作者:Walther, G
作者单位:Stanford University
摘要:A special semiparametric model for a univariate density is introduced that allows analyzing a number of problems via appropriate transformations. Two problems treated in some detail are testing for the presence of a mixture and detecting a wear-out trend in a failure rate. The analysis of the semiparametric model leads to an approach that advances the maximum likelihood theory of the Grenander estimator to a multiscale analysis. The construction of the corresponding test statistic rests on an ...
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作者:Breidt, FJ; Davis, RA; Trindade, AA
作者单位:Colorado State University System; Colorado State University Fort Collins; State University System of Florida; University of Florida
摘要:An autoregressive moving average model in which all of the roots of the autoregressive polynomial are reciprocals of roots of the moving average polynomial and vice versa is called an all-pass time series model. All-pass models generate uncorrelated (white noise) time series, but these series are not independent in the non-Gaussian case. An approximation to the likelihood of the model in the case of Laplacian (two-sided exponential) noise yields a modified absolute deviations criterion, which ...
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作者:Wang, WZ; Voss, DT
作者单位:University System of Ohio; Wright State University Dayton
摘要:Individual and simultaneous confidence intervals using the data adaptively are constructed for the effects in orthogonal saturated designs under the assumption of effect sparsity. The minimum coverage probabilities of the intervals are equal to the nominal level 1-alpha.
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作者:Shoung, JM; Zhang, CH
作者单位:Rutgers University System; Rutgers University New Brunswick
摘要:In this paper, we consider nonparametric least squares estimators of the mode of an unknown unimodal regression function. We establish almost sure convergence of these estimators with nearly optimal convergence rates, under the assumption of the exponential tail for the error distributions.
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作者:Hristache, M; Juditsky, A; Polzehl, J; Spokoiny, V
作者单位:Ecole Nationale de la Statistique et de l'Analyse de l'Information (ENSAI); Leibniz Association; Weierstrass Institute for Applied Analysis & Stochastics
摘要:We propose a new method of effective dimension reduction for a multi-index model which is based on iterative improvement of the family of average derivative estimates. The procedure is computationally straightforward and does not require any prior information about the structure of the underlying model. We show that in the case when the effective dimension in of the index space does not exceed 3, this space can be estimated with the rate n (-1/2) under rather mild assumptions on the model.
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作者:Hall, P; Kang, KH
作者单位:Australian National University; Hankuk University Foreign Studies
摘要:We examine the way in which empirical bandwidth choice affects distributional properties of nonparametric density estimators. Two bandwidth selection methods are considered in detail: local and global plug-in rules. Particular attention is focussed on whether the accuracy of distributional bootstrap approximations is appreciably influenced by using the resample version (h) over cap*, rather than the sample version (h) over cap, of an empirical bandwidth. It is shown theoretically that, in mark...
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作者:Patilea, V
作者单位:Universite de Orleans
摘要:We analyze the asymptotic behavior of maximum likelihood estimators (MLE) in convex dominated models when the true distribution generating the independent data does not necessarily belong to the model. Inspired by the Hellinger distance and its properties, we introduce a family of divergences (contrast functions) which allow a unified treatment of well- and misspecified convex models. Convergence and rates of convergence of the MLE with respect to our divergences are obtained from inequalities...
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作者:Gill, RD; Robins, JM
作者单位:Utrecht University; Harvard University; Harvard T.H. Chan School of Public Health
摘要:We extend Robins' theory of causal inference for complex longitudinal data to the case of continuously varying as opposed to discrete covariates and treatments. In particular we establish versions of the key results of the discrete theory: the g-computation formula and a collection of powerful characterizations of the g-null hypothesis of no treatment effect. This is accomplished under natural continuity hypotheses concerning the conditional distributions of the outcome variable and of the cov...
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作者:James, LF; Preibe, CE; Marchette, DJ
作者单位:Johns Hopkins University; United States Department of Defense; United States Navy
摘要:The consistent estimation of mixture complexity is of fundamental importance in many applications of finite mixture models. An enormous body of literature exists regarding the application, computational issues and theoretical aspects of mixture models when the number of components is known, but estimating the unknown number of components remains an area of intense research effort. This article presents a semiparametric methodology yielding almost sure convergence of the estimated number of com...
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作者:Hall, P; Huang, LS
作者单位:Australian National University; Commonwealth Scientific & Industrial Research Organisation (CSIRO)
摘要:We suggest a method for monotonizing general kernel-type estimators, for example local linear estimators and Nadaraya-Watson estimators. Attributes of our approach include the fact that it produces smooth estimates, indeed with the same smoothness as the unconstrained estimate. The method is applicable to a particularly wide range of estimator types, it can be trivially modified to render an estimator strictly monotone and it can be employed after the smoothing step has been implemented. There...