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作者：BROWN, BM
摘要：The average of 2 complementary order statistics is termed a symmetric quantile average. In addition to having good efficiency, robustness and computational properties, exact nonparametric confidence intervals for location can be derived from it. A related type of estimator called a combined quantile average is introduced; it is slightly more difficult to compute than the symmetric quantile average, but can have better efficiency and robustness properties. The recommended form of combined quant...
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作者：CAMPBELL, G
作者单位：Purdue University System; Purdue University
摘要：The estimation of a bivariate distribution function with randomly censored data is considered. [Times to death or times to initial contraction of a disease are of interest for litter mate pairs of rats or for twin studies in humans. The time to a deterioration level or the time to reaction of a treatment is of interest in pairs of lungs, kidneys, eyes or ears of humans.] It is assumed that the censoring occurs independently of the lifetimes and that deaths and losses which occur simultaneously...
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作者：CHERNOFF, H; PETKAU, AJ
作者单位：Massachusetts Institute of Technology (MIT); University of British Columbia
摘要：A general approach to sequential decision-theoretic problems is illustrated with Anscombe''s formulation concerning the problem of comparing 2 treatments in a medical trial. The Bayes sequential procedure for a continuous time version of the problem is explicitly determined. Suboptimal procedures are proposed and evaluated; asymptotic results and numerical descriptions are provided. The continuous time version provides accurate approximations even for clinical trials involving relatively small...
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作者：PETTITT, AN; SISKIND, V
作者单位：University of Queensland; University of Queensland
摘要：Motivated by a problem involving correlation due to genetic relationships within a sample, [the R1R1 relatives of an Rh-null individual (Race and Sanger, 1975) were to be compared with a random sample of unrelated R1R1 blood donors with respect to the levels of certain antigens] the effect of within-sample dependence and between-sample independence on the variance of the Mann-Whitney-Wilcoxon statistic, given that the marginal distributions are identical in each sample, was investigated. The d...
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作者：EJIGOU, A; MCHUGH, R
作者单位：University of Minnesota System; University of Minnesota Twin Cities
摘要：Under multiple matching, relative risk from a rare disease is estimated in a retrospective design. Maximum likelihood estimation is carried out using an unconditional probability model. This model is used to derive a new estimator of relative risk which is noniterative but is as efficient, asymptotically, as the maximum likelihood estimator.
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作者：WANG, MC; VANRYZIN, J
作者单位：Washington State University; Columbia University
摘要：A class of smooth weight function estimators for discrete distributions is presented. Any estimator in the class depends on choosing a parameterized set of weights. The resulting estimators are strongly consistent and asymptotically normal under mild regularity conditions. A general procedure for choosing the weight function smoothing parameter is given along with specific solutions in some cases. Mean squared error comparisons with the maximum likelihood estimator based on large-sample theory...
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作者：LUBIN, JH
作者单位：National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI)
摘要：A Monte Carlo study is made of conditional and unconditional likelihoods in the analysis of case-control data where the underlying disease incidence is assumed to follow a logistic model. Results indicate that the full likelihood may yield estimates of relative risk that are unacceptably biased upwards for strata with fewer than 20 cases and 20 controls. The simulations support the need for better approximations to the conditional likelihood. With 1 to R matched studies the bias of the full li...
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作者：ATKINSON, AC
摘要：The paper describes 2 procedures for detecting observations with outlying values either in the response variable or in the explanatory variables in multiple regression. These procedures are presented as 1/2 normal plots with envelopes derived from simulation in order to avoid overinterpretation of the data. Analysis of a well-known data set leads to the use of a data transformation and to comments on the relationship with robust regression.
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作者：SEBER, GAF; FELTON, R
作者单位：University of Auckland
摘要：A problem in the Petersen capture-mark-recapture experiment (Seber, 1973) is the possible loss of tags. The effect of such a loss on the usual estimate of population size and the estimate of its variance is investigated for both single and double tagging. When there is double tagging, a correction for tag loss can be made based on the numbers recaptured that retain 1 or both tags, provided independence of the tags can be assumed. Two cases are considered, distinguishable tags and nondistinguis...
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作者：KALBFLEISCH, JD; PRENTICE, RL
作者单位：Fred Hutchinson Cancer Center
摘要：Simple estimators of the average hazard ratio are obtained for 2 sample problems with censored failure time data. These estimators are compared with estimators arising out of the partial likelihood within the proportional hazards class. Efficiency results are generally favorable provided the hazard ratio is not too large. Comments are made on extensions to the k sample problem.
