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作者：Shih, JH
作者单位：National Institutes of Health (NIH) - USA; NIH National Heart Lung & Blood Institute (NHLBI)
摘要：We propose a-simple test of constant conditional hazard ratio in the Clayton model (1978) by comparing the unweighted and weighted concordance estimators of the association parameter. If the Clayton model holds, the difference of these two estimates converges to zero. The proposed test is consistent against alternatives under which the two concordance estimators converge to different values. We derive an explicit-formula for the asymptotic variance and derive the asymptotic distribution of the...
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作者：Roeder, K; Escobar, M; Kadane, JB; Balazs, I
作者单位：Carnegie Mellon University; University of Toronto; Carnegie Mellon University
摘要：As currently defined, DNA fingerprint profiles do not uniquely identify individuals. For criminal cases involving DNA evidence, forensic scientists evaluate the conditional probability that an unknown, but distinct, individual matches the crime sample, given that the defendant matches. Estimates of the conditional probability of observing matching profiles are based on reference populations maintained by forensic testing laboratories. Each of these databases is heterogeneous, being composed of...
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作者：Li, B
作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
摘要：For improving on quasilikelihood-estimation two types of quadratic estimating equations have been proposed, one based on the Edgeworth expansion, the other on the generalisation of the quasi-score. The first requires that the skewness of observations has a small departure from the exponential family; the second requires the knowledge of both skewness and kurtosis. We introduce an optimal quadratic estimating equation applicable when the skewness is not small and the-kurtosis is unknown;Apart f...
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作者：Brown, BM; Cowling, A
作者单位：University of Tasmania; Commonwealth Scientific & Industrial Research Organisation (CSIRO)
摘要：This paper considers the estimation of clustering parameters and mean species intensity based on likelihood theory for the simplified Neyman-Scott Poisson model, with observations taken from line transect surveys with a Gaussian detection function. The estimators and accompanying standard error expressions are tractable and easy to calculate, and, coming from likelihood methods, often will have high efficiency. Such properties compare favourably with those of existing K-function methods which ...
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作者：Cooley, CA; MacEachern, SN
作者单位：University System of Ohio; Ohio State University
摘要：Multivariate kernel density estimation is often used as the basis for a nonparametric classification technique. However, the multivariate kernel classifier suffers from the curse of dimensionality, requiring inordinately large sample sizes to achieve a reasonable degree of accuracy in high dimensional settings. A variance stabilising approach to kernel classification can be motivated through an alternative interpretation of linear and quadratic discriminant analysis in which rotations of the c...
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作者：Troxel, AB; Lipsitz, SR; Harrington, DP
作者单位：Columbia University; Harvard University; Harvard T.H. Chan School of Public Health
摘要：We propose methods for the analysis of continuous responses subject to nonignorable non-monotone missing data. We form a pseudolikelihood by naively assuming independence over time and using a product of marginal likelihoods at each time point, and we obtain consistent and asymptotically normal estimators of the mean and missingness parameters. Our primary interest is in estimating the parameters of the marginal model at each time point, and we make no assumption about the correlation structur...
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作者：Nadeau, C; Lawless, JF
作者单位：Universite de Montreal; University of Waterloo
摘要：Liang & Zeger (1986) introduced methodology for the analysis of longitudinal data that provides an alternative to likelihood-based inference. They considered modelling the marginal means of the response follow-up measures, and proposed the use of unbiased estimating functions to handle inference. Here we wish to do the same for point or jump processes. We consider parametric models for the marginal means, and possibly the covariance structures, of processes that allow covariates. Inference is ...
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作者：Shi, P; Fung, WK
作者单位：Peking University; University of Hong Kong
摘要：For the problem of choosing a transformation h(y) of a univariate response variable y to achieve the linearity of the regression function E{h(y)\x}, we view Cook & Weisberg's (1994) method as an iterative procedure and estimate the transformed linear model based on the fixed point of the iteration procedure. When the procedure is implemented with B-spline smoothing by projecting the function h(y) into a B-spline space, it is proved that the fixed point is identical to the solution obtained fro...
