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作者：Tsiatis, AA; Ma, YY
作者单位：North Carolina State University; North Carolina State University
摘要：A class of semiparametric estimators are proposed in the general setting of functional measurement error models. The estimators follow from estimating equations that are based on the serniparametric efficient score derived under a possibly incorrect distributional assumption for the unobserved 'measured with error' covariates. It is shown that such estimators are consistent and asymptotically normal even with misspecification and are efficient if computed under the truth. The methods are demon...
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作者：Jewell, NP; van der Laan, M
作者单位：University of California System; University of California Berkeley
摘要：In this paper, we show that the distribution function of survival times is identified, up to a one-parameter family of distribution functions, based on information from case-control current status data. With supplementary information on the population frequency of cases relative to controls, a simple weighted version of the nonparametric maximum likelihood estimator for prospective current status data provides a natural estimator for case-control samples. Following the parametric results of Sc...
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作者：Gangnon, RE; Kosorok, MR
作者单位：University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison
摘要：We present a simple sample-size formula for weighted log-rank statistics applied to clustered survival data with variable cluster sizes and arbitrary treatment assignments within clusters. This formula is based on the asymptotic normality of weighted log-rank statistics under certain local alternatives in the clustered data context. We also provide consistent variance estimators. The derived sample-size formula reduces to Schoenfeld's (1983) formula for cases of no clustering or independence w...
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作者：Goldwasser, MA; Tian, L; Wei, LJ
作者单位：Harvard University; Harvard T.H. Chan School of Public Health
摘要：Suppose that a consistent estimator for an infinite-dimensional parameter can be readily obtained via a set of estimating functions which has a 'good' local linear approximation around the true value of the parameter. However, it may be difficult to estimate the variance function of this estimator well. We show that, if the set of estimating functions evaluated at the true parameter value is 'asymptotically pivotal', then the 'fiducial' distribution of the parameter can be used to approximate ...
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作者：Konishi, S; Ando, T; Imoto, S
作者单位：Kyushu University; University of Tokyo
摘要：By extending Schwarz's (1978) basic idea we derive a Bayesian information criterion which enables us to evaluate models estimated by the maximum penalised likelihood method or the method of regularisation. The proposed criterion is applied to the choice of smoothing parameters and the number of basis functions in radial basis function network models. Monte Carlo experiments were conducted to examine the performance of the nonlinear modelling strategy of estimating the weight parameters by regu...
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作者：Kelderman, H
作者单位：Vrije Universiteit Amsterdam
摘要：The one-factor model restricts the covariance structure of the observed variables on the basis of assumptions about their relationship with an unobserved variable. It is hard to justify these assumptions on substantive or empirical grounds. In this paper, alternative measurement models are proposed that are based on exchangeability of variables after admissible scale transformations. They provide an alternative interpretation of the model and do not involve unobserved variables. They also yiel...
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作者：Critchley, F; Marriott, P
作者单位：Open University - UK; National University of Singapore
摘要：The likelihood-based influence analysis methodology introduced in Cook (1986) uses a parameterised space of local perturbations of a base model. It is frequently the case that such perturbation schemes involve more parameters of interest and perturbation parameters than there are observations, and hence the perturbation space is often explored rather than estimated, where exploration means discovering the effect on inference of putatively choosing values of perturbation parameters. This paper ...
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作者：Whittemore, AS
作者单位：Stanford University
摘要：We consider the problem of estimating a parameter theta reflecting association between a disease and genotypes of a genetic polymorphism, using nuclear family data. In many applications, some parental genotypes are missing, and the distribution of these genotypes is unknown. Since misspecification of this distribution can bias estimators for theta, we consider estimating functions that are unbiased, regardless of how the distribution is specified. We call the resulting estimators parental-geno...
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作者：Watanabe, T; Omori, Y
作者单位：Tokyo Metropolitan University; University of Tokyo
摘要：This note points out a problem in the multi-move sampler as proposed by Shephard & Pitt (1997) and provides an alternative correct formulation.
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作者：Lu, WB; Ying, ZL
作者单位：Columbia University
摘要：A general class of semiparametric transformation cure models is studied for the analysis of survival data with long-term survivors. It combines a logistic regression for the probability of event occurrence with the class of transformation models for the time of occurrence. Included as special cases are the proportional hazards cure model (Farewell, 1982; Kuk Chen, 1992; Sy Taylor, 2000; Peng & Dear, 2000) and the proportional odds cure model. Generalised estimating equations are proposed for p...
