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作者：DONNER, A
摘要：Liang (1985) proposed an alternative to the Mantel-Haenszel procedure for testing the significance of an estimated common odds ratio when the binomial assumption for the observed cell frequencies is relaxed. It is shown that this procedure is a form of Fisher''s one-sample permutation test.
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作者：ROBERTS, G; RAO, JNK; KUMAR, S
作者单位：Carleton University
摘要：Standard chi-squared, X2, or likelihood ratio, G2, test statistics for logistic regression analysis, involving a binary response variable, are adjusted to take account of the the survey design. These adjustments are based on certain generalized design effects. Logistic regression diagnostics to detect any outlying cell proportions in the table and influential points in the factor space are also developed, taking account of the survey design. Finally, the results are used to analyse some data f...
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作者：WANG, YCJ
作者单位：Rutgers University System; Rutgers University New Brunswick; Rutgers University Camden
摘要：After partitioning the plane into fine rectangular regions, the bivariate normal probability integrals over all the rectangular regions can be considered as a population contingency table. The row and column marginals of this contingency table are two discretized univariate normal distributions. The logarithm of the local cross-product ratios are approximately linear. Given the correlation coefficient of the bivariate normal, a contingency table with discretized normal marginals and proper cro...
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作者：BEGG, CB; GRAY, RJ
作者单位：Harvard University; Harvard University Medical Affiliates; Dana-Farber Cancer Institute; Harvard Medical School
摘要：A method is developed for the analysis of case-control studies with prevalent cases. The method permits adjustments for potential bias induced by association of the exposure of interest and/or covariates with survival. The only additional information required is the time since diagnosis of each prevalent case. The method employs an accelerated life model, the parameters of which are estiamted using quasi-likelihood techniques. In this way, no assumptions are required about the random component...
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作者：ROSENBAUM, PR
摘要：In observational studies, treatments are not randomly assigned to experiental units, so that randomization tests and their associated interval estimates are not generally applicable. In an effort to compensate for the lack of randomization, treated and control units are often matched on the basis of observed covariates; however, the possibility remains of bias due to residual imbalances in unobserved covariates. A general though simple method is proposed for displaying the sensitivity of permu...
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作者：DUCHARME, GR; MILASEVIC, P
作者单位：University of Fribourg
摘要：We introduce the normalized spatial median as an estimator of location for rotationally symmetric distributions on the hypersphere. We investigate some of its asymptotic properties and use them to obtain confidence regions for the modal direction of a distribution on the hypersphere. These results are then applied to the von Mises-Fisher distribution and to a contamination model. It is seen that the normalized spatial median can perform more efficiently than the normalized mean in presence of ...
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作者：KIM, K; DEMETS, DL
摘要：Lan and DeMets (1983) devised a method for constructing discrete group sequential boundaries by using the type I error spending rate function. It is extended so as to generate asymmetric as well as symmetric two-sided boundaries for clinical trials. The design aspect of this procedure is explored in terms of the maximum sample size needed to achieve a desired level of power and the expected stopping times under both null and alternative hypotheses. Finally, these properties are employed in sea...
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作者：RAAB, GM; YU, JZ
摘要：The consistent least-squares estimator, proposed by Jewell (1985) for linear regression with data arising from stratified samples, lacks invariance with respect to a change of location of the dependent variable. Simulation suggests that its efficiency is reduced when the origin of the dependent variable is far from its mean. This estimator can be made invariant to a change of location by specifying that the dependent variable is measured from the estimated population mean. Another similar inva...
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作者：BAILEY, RA
摘要：The problem of one-dimensional blocking in two-way layouts is discussed. A valid restricted randomization scheme is given for complete-block designs. This can be used to overcome the problem when the number of treatments is a prime power.
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作者：JENNISON, C
摘要：We derive group sequential tests to minimize expected sample size. A parametric family of group sequential tests is proposed containing tests which are nearly optimal, in terms of minimizing expected sample size, amongst all group sequential tests. These parametric tests can be implemented when group sizes are unequal and unpredictable. They are shown to achieve error rates close to their nominal level in a wide range of situations and to be efficient when compared with other tests based on th...
