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作者：SIMPSON, DG; MARGOLIN, BH
作者单位：National Institutes of Health (NIH) - USA; NIH National Institute of Environmental Health Sciences (NIEHS)
摘要：A general recursive strategy is introduced to test nonparametrically for an increasing dose-response relationship when a downturn in response at high doses is possible. A specific implementation involving a test of Jonckheere (1954) and Terpstra (1952) is considered, and it''s size and power properties are investigated via Monte Carlo methods. Data from mutation research illustrate the phenomenon of concern.
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作者：MOORE, DF
摘要：Consistency and asymptotic normality of moment estimates of regression parameters and an overdispersion parameter are shown for data with extra-binomial and extra-Poisson variation. The asymptotic covariance of the regression parameters is found to be unaffected by estimation of the overdispersion parameter. The moment estimates may be obtained using iterated weighted least squares.
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作者：MALLET, A
摘要：A method for estimating the distribution of the parameters of a random coefficient regression model is proposed. This distribution, accounting for interindividual variability, is assumed to lie in a wide class of probability distributions rather than in a given parametric class. Estimation is based on observations from a sample of individuals and likelihood is the estimation criterion. Experimental designs may be different among individuals, allowing the method to apply to routinely collected ...
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作者：PETRUCCELLI, JD; DAVIES, N
作者单位：Nottingham Trent University
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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：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：PATEL, HI
摘要：A multivariate model is proposed for analysing repeated measures designs with changing or within-subject covariates. Under the assumption of multivariate normality the likelihood ratio tests are derived for testing certain linear hypotheses. Some special designs are discussed and a numerical example is given to illustrate the method for analysing a two-period crossover design.
