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作者：Brehm, J
作者单位：Duke University
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作者：Boneh, S; Boneh, A; Caron, RJ
作者单位：Technion Israel Institute of Technology; University of Windsor
摘要：A sample of N units is taken from a population consisting of an unknown number of species. We are interested in estimating the number of species and the prediction function for future sampling. The prediction function is defined as the expected number of new species that will be found if an additional sample of size tN is taken for any positive real number t. In this paper we point out that an estimator suggested by Efron and Thisted lacks some essential properties of the true prediction funct...
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作者：Minnotte, MC
作者单位：Utah System of Higher Education; Utah State University
摘要：A method is proposed for achieving fast-O(n(-8/9)) and faster-asymptotic mean integrated squared error (AMISE) convergence rates in density estimation using data condensed to standard histogram bin counts and edges. The method involves the two elements of B splines and the correct mass proportions property, in which the probability mass for the histogram bins equals exactly the fraction of the data found in those bins. It is shown that the asymptotic bias of such an estimate using a spline of ...
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作者：Whittemore, AS; Halpern, J; Gong, G
作者单位：Stanford University
摘要：Recent interest in modeling multivariate responses for members of groups has emphasized the need for testing goodness of fit. Here we describe a way to test the covariance structure of a multivariate distribution parameterized by a vector theta. The idea is to extend this distribution, the null distribution, to a more general distribution that depends on theta, an additional scalar gamma, and a specific quadratic function of the response vector chosen to capture features of an alternative cova...
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作者：Lancaster, VA; Keller-McNulty, S
作者单位：United States Department of Energy (DOE); Los Alamos National Laboratory
摘要：A composite is formed by collecting multiple sample units and combining them in their entirety or in part, to form a new sample. The sample units that make up the composite may retain their integrity or be homogenized through physical processes such as ball milling, sieving, shaking, or centrifuging. One or more subsequent measurements are taken on the composite and the information on the sample units is lost. This counterintuitive loss of information has fueled opposition to composite samplin...
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作者：Chu, CK; Glad, IK; Godtliebsen, F; Marron, JS
作者单位：National Tsing Hua University; UiT The Arctic University of Tromso; University of Oslo; University of North Carolina; University of North Carolina Chapel Hill
摘要：Classical smoothers have limited usefulness in image processing, because sharp edges tend to be blurred. There is a literature on edge-preserving smoothers, but these all require moderately large smooth stretches. Here we discuss an approach to this problem called sigma filtering and propose an improvement based on running M estimation. Both computational and theoretical aspects are developed. For image processing, the methods have a niche between standard filtering approaches and Bayes-Markov...
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作者：Maitra, R; O'Sullivan, F
作者单位：University System of Maryland; University of Maryland Baltimore County; University College Cork
摘要：The problem of variance assessment for positron emission tomography (PET) image reconstructions is considered in the context of generalized deconvolution. A refinement of an approximate technique proposed by Carson and colleagues is examined. Computational implications of representing the reconstruction kernel in terms of a weighted sum of Gaussian densities are developed. Bias and variance characteristics of the resulting variance estimators are examined by numerical simulation. For typical r...
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作者：Ge, NX; Simpson, DG
作者单位：University of Illinois System; University of Illinois Urbana-Champaign
摘要：Classical discriminant analysis breaks down when the feature vectors are of extremely high dimension; for example, when the basic observation is a random function observed over a fine grid. Alternative methods have been developed assuming a simplified form for the covariance structure. We analyze the high-dimensional asymptotics of some of these methods, emphasizing the effects of correlations such as occur when the baseline is random. For instance, the Euclidean distance classifier, which has...
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作者：Gersovitz, M; Jacoby, HG; Dedy, FS; Tape, AG
作者单位：Johns Hopkins University; The World Bank; Ecole Normale Superieure (ENS) d'Abidjan
摘要：The AIDS epidemic in Africa depends on heterosexual behavior, about which little is known. National Knowledge, Attitudes and Practices (KAP) surveys are a potentially important data source but are compromised because women report less-often, much less-sexual activity than men. This imbalance is investigated using questions on the type of activity (with regular or casual partners and involving compensation) and on the duration of abstinence (time since last act), as well as other socioeconomic ...
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作者：Wang, YN; McDermott, MP
作者单位：University of Rochester
摘要：The conditional likelihood ratio test is derived for significance of a multivariate mean having nonnegative components. This test is shown to be uniformly more powerful than the unconditional likelihood ratio test derived by Perlman. The computation involved in the new test is a straightforward progamming task. Simulation results suggest that this test is also uniformly more powerful than a half-space test proposed by Tang and Hotelling's T-2 test. The consistency, invariance and unbiasedness ...
