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作者:LI, WK; MCLEOD, AI
作者单位:Western University (University of Western Ontario)
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作者:SIMES, RJ
摘要:A modification of the Bonferroni procedure for testing multiple hypotheses is presented. The method, based on the ordered p-values of the individual tests, is less conservative than the classical Bonferroni procedure but is still simple to apply. A simulation study shows that the probability of a type I error of the procedure does not exceed the normal significance level, .alpha., for a variety of multivariate normal and multivariate gamma test statistics. For independent tests the procedure h...
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作者:MARTIN, RJ
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作者:PRENTICE, RL
摘要:Suppose that a cohort of individuals is to be followed in order to relate failure rates to preceding covariate histories. A design is proposed which involves covariate data only for cases experiencing failure and for members of a randomly selected subcohort. Odds ratio and relative risk estimation procedures are presented for such a ''case-cohort'' design. A small simulation study compares case-cohort relative risk estimation procedures to full-cohort and synthetic case-control analyses. Relev...
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作者:TAM, SM
摘要:This paper presents the necessary and sufficient conditions for the optimality of an arbitrary linear predictor of the total of a finite population in survey sampling under a general linear model with a symmetric and positive-definite covariance matrix. Results of the paper extend and unify earlier work on robust estimation in survey sampling under more restrictive conditions.
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作者:SCHNEIDER, H; WEISSFELD, L
作者单位:University of Michigan System; University of Michigan
摘要:Three methods for linear regression with censored data are considered, that of Buckley and James (1979), a proposed simpler nonparametric method and a normal model for censored data. A new estimator for the variance of the error term in Buckley and James''s (1979) procedure is proposed and simulations comparing the three methods are described.
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作者:SUNDBERG, R
摘要:For dichotomous longitudinal panel data assumed to have been generated by a Markov chain but with only one of it''s states identifiable, the likelihood ratio and related tests for underlying Markovian structure are studied. It is shown that the likelihood ratio may be written as a product of conditionally independent likelihood ratios for testing independence in certain contingency tables, given margins. The tests are illustrated on data from malaria and schistosomiasis surveys.
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作者:CHAMBERS, RL; DUNSTAN, R
摘要:A simple method for estimating population distribution functions and associated quantiles from sample survey data is described and some asymptotic theory for it presented. The method assumes a model-based approach to survey estimation and allows auxillary population information to be directly incorporated into the estimation process. Monte Carlo results comparing the proposed method with conventional design-based methods are given. These suggest that the model-based approach offers significant...
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作者:PETTITT, AN
摘要:Maximum likelihood estimation of a vector regression parameter and variance components is considered for the mixed effects model when observations are right censored. A general scheme of estimation is given using the EM algorithm and detailed results found for the model with between and within block variation. This model is applied to the logarithms of survival times from a repeated measures design.
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作者:LIANG, KY; ZEGER, SL
摘要:This paper proposes an extension of generalized linear models to the analysis of longitudinal data. We introduce a class of estimating equations that give consistent estimates of the regression parameters and of their variance under mild assumptions about the time dependence. The estimating equations are derived without specifying the joint distribution of a subject''s observations yet they reduce to the score equations for multivariate Gaussian outcomes. Asymptotic theory is presented for the...