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作者：DARROCH, JN; MCCLOUD, PI
作者单位：Monash University
摘要：Two or more responses measured on a randomly selected individual can be dependent for two quite different reasons. In the first place they can be dependent within, that is conditional upon, each individual. Secondly, dependence is created simply from the heterogeneity between individuals. This paper addresses a rare instance of being able to measure separately the dependence from the two sources. The data comprise frequencies of the infection profiles for a sample of individuals exposed to fou...
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作者：EBRAHIMI, N; HABIBULLAH, M
作者单位：University of Wisconsin System
摘要：The cumulative distribution function F, of a nonnegative random variable, is said to be new better than used of specified age t0 if .hivin.F (x + t0) .ltoreq. .hivin.F (x) .hivin.F (t0) for all .gtoreq. 0, where .hivin.F = 1 - F. Let A = {F:.hivin.F (x = t0) = .hivin.F (x) .hivin.F (t0), for all x .gtoreq. 0}. We propose a class of test statistics Tk, indexed by a positive integer k, for testing the null hypothesis that F belongs A against the alternative hypothesis that F is new better than u...
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作者：HOOVER, DR; GUESS, FM
作者单位：Johns Hopkins University; University of Tennessee System; University of Tennessee Knoxville
摘要：A form of positive dependence between censoring time and response time is defined as response linked, RL, censoring. We present a method for modelling, estimation and detection of RL censoring in situations where both RL and independent censoring can occur. This method involves parametric modelling with covariates and is illustrated with the Stanford heart transplant data. Other applications are mentioned.
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作者：JONES, RH; ACKERSON, LM
作者单位：National Jewish Health
摘要：Serial correlation in the within subject error structure in longitudinal data with unequally spaced observations is modelled using continuous time autoregressive moving averages. The models considered have both fixed and random effects in addition to serially correlated within subject errors. Two approaches are presented for calculating the exact likelihood for a model when the errors are Gaussian. The first calculates the covariance matrices for each subject for assumed values of the unknown ...
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作者：HORN, PS
摘要：In this study we propose quantile estimators for a variety of skewed distributions. The proposed estimators are based on the biweight estimators for symmetric populations (Horn, 1988). These achieve good coverage across a wide variety of skewed populations, even for sample sizes as small as ten.
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作者：MARX, BD; SMITH, EP
作者单位：Virginia Polytechnic Institute & State University
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作者：BEGG, CB
摘要：Wei (1988) analyzed data from a clinical trial in which an urn-sampling model was used to allocate patients to treatments. The trial resulted in 11 patients being allocated to the experimental treatment, all successes, and with one patient allocated to the control treatment, a failure. Wei analyzed these data using a randomization algorithm and concluded that the results were almost significant at p = 0.051. He asserted that an analysis which ignored the design and presumed complete randomizat...
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作者：HELLER, G; SIMONOFF, JS
作者单位：New York University
摘要：Several methods of estimating parameters in a linear regression when the response variable is censored are compared. The estimator of Buckley and James (1979) is preferred. Further, it is shown that the strength of the regression, the support and distribution of the censoring variable, and the magnitude of the slope all have an effect on the relative performance of the estimators.
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作者：EMERSON, SS; FLEMING, TR
作者单位：University of Washington; University of Washington Seattle
摘要：Parameter estimation techniques which fail to adjust for the interim analyses of group sequential test designs will introduce bias in much the same way that the repeated use of single sample hypothesis testing causes inflation of the type one statistical error rate. Methods based on the duality of hypothesis testing and interval estimation require definition of an ordering for the outcome space for the test statistic. In this paper, estimation following a group sequential hypothesis test for t...
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作者：STERN, H
摘要：An approach to building models for paired comparisons experiments based on comparisons of gamma random variables is considered. The probability that one object is preferred to a second object is taken to be the probability that one gamma random variable with shape parameter r is less than a second independent gamma random variable with the same shape parameter but a different scale parameter. This is motivated by considering a point scoring competition as the basis for each period comparison. ...
