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作者:Pitt, Michael; Chan, David; Kohn, Robert
作者单位:University of Warwick; University of New South Wales Sydney
摘要:A Gaussian copula regression model gives a tractable way of handling a multivariate regression when some of the marginal distributions are non-Gaussian. Our paper presents a general Bayesian approach for estimating a Gaussian copula model that can handle any combination of discrete and continuous marginals, and generalises Gaussian graphical models to the Gaussian copula framework. Posterior inference is carried out using a novel and efficient simulation method. The methods in the paper are ap...
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作者:Wang, Xinlei; Lim, Johan; Stokes, S. Lynne
作者单位:Southern Methodist University; Yonsei University; Southern Methodist University
摘要:For the problem of dual system estimation, we propose a Bayesian treed capture-recapture model to account for heterogeneity of capture probabilities where individual auxiliary information is available. The model uses a binary tree to partition the covariate space into 'homogeneous' regions, within each of which the capture response can be described adequately by a simple model that assumes equal catchability. The attractive features of the proposed model include reduction of correlation bias, ...
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作者:Tian, Lu; Cai, Tianxi
作者单位:Northwestern University; Harvard University
摘要:This paper introduces a novel approach to making inference about the regression parameters in the accelerated failure time model for current status and interval censored data. The estimator is constructed by inverting a Wald-type test for testing a null proportional hazards model. A numerically efficient Markov chain Monte Carlo based resampling method is proposed for obtaining simultaneously the point estimator and a consistent estimator of its variance-covariance matrix. We illustrate our ap...
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作者:Lin, N; He, XM
作者单位:Washington University (WUSTL); University of Illinois System; University of Illinois Urbana-Champaign
摘要:The minimum Hellinger distance estimator is known to have desirable properties in terms of robustness and efficiency. We propose an approximate minimum Hellinger distance estimator by adapting the approach to grouped data from a continuous distribution. It is easier to compute the approximate version for either the continuous data or the grouped data. Given certain conditions on the model distribution and reasonable grouping rules, the approximate minimum Hellinger distance estimator is shown ...
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作者:Rodland, Einar Andreas
作者单位:University of Oslo; National Hospital Norway
摘要:Although Simes' modification of the Bonferroni procedure tends to perform very well, albeit often being slightly liberal for negatively dependent hypotheses, there are special cases where it fails more dramatically. We prove that these special cases are indeed special, applying only to specific significance levels, and obtain a strong bound on the average deviation of the Simes corrected P-value from the true probability over any interval of P-values. From this, it is argued that Simes' proced...
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作者:Wang, Xue; Wood, Andrew T. A.
作者单位:University of Bristol; University of Nottingham
摘要:Empirical Bayes approaches to the shrinkage of empirical wavelet coefficients have generated considerable interest in recent years. Much of the work to date has focussed on shrinkage of individual wavelet coefficients in isolation. In this paper we propose an empirical Bayes approach to simultaneous shrinkage of wavelet coefficients in a block, based on the block sum of squares. Our approach exploits a useful identity satisfied by the noncentral chi(2) density and provides some tractable Bayes...
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作者:Cook, RD; Ni, LQ
作者单位:University of Minnesota System; University of Minnesota Twin Cities; State University System of Florida; University of Central Florida
摘要:Popular methods for estimating the central subspace in regression require slicing a continuous response. However, slicing can result in loss of information and in some cases that loss can be substantial. We use intraslice covariances to construct improved inference methods for the central subspace. These methods are optimal within a class of quadratic inference functions and permit chi-squared tests of conditional independence hypotheses involving the predictors. Our experience gained through ...
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作者:Pintore, A; Speckman, P; Holmes, CC
作者单位:University of Oxford; University of Missouri System; University of Missouri Columbia
摘要:We use a reproducing kernel Hilbert space representation to derive the smoothing spline solution when the smoothness penalty is a function lambda(t) of the design space t, thereby allowing the model to adapt to various degrees of smoothness in the structure of the data. We propose a convenient form for the smoothness penalty function and discuss computational algorithms for automatic curve fitting using a generalised crossvalidation measure.
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作者:Steinberg, David M.; Lin, Dennis K. J.
作者单位:Tel Aviv University; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
摘要:The Latin hypercube design is a popular choice of experimental design when computer simulation is used to study a physical process. These designs guarantee uniform samples for the marginal distribution of each single input. A number of methods have been proposed for extending the uniform sampling to higher dimensions.We show how to construct Latin hypercube designs in which all main effects are orthogonal. Our method can also be used to construct Latin hypercube designs with low correlation of...
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作者:Lawless, J. F.; Babineau, Denise
作者单位:University of Waterloo; Cleveland Clinic Foundation
摘要:Interval-censored lifetime data arise when individuals in a study are inspected intermittently so that a lifetime is observed to lie between two successive times. In settings where only these two times are available, methods exist for nonparametric or parametric estimation of lifetime distributions. However, there has been virtually no discussion of how inspection processes may be estimated or identified. Such estimates are needed if one is to generate interval-censored data by simulation. Thi...