摘要:

AbstractGiven are k(≧2) exponential populations differing only in their location parameter. One wishes to choose the best one, that is the population with the largest value of the location parameter. A possible method for solving this problem is to select a subset of the k populations of size at least one which includes the best population with a required confidenceP*(k−1≤P* ≤1). In this paper the required selection constant is determined for different values ofkandP*. Also an approximation for the selection constant is derived. A comparison with the exact results

ISSN:0323-3847    

DOI:10.1002/bimj.4710370502

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractA general approach to repeated measures analysis described in MCGILCHRIST and CULLIS (1991) is extended to general linear models in which there is a homogeneous correlation structure such as a stationary process but the variances are heterogeneous over time. Models for the variance heterogeneity are suggested and results are applied to data examining the effect of enzootic pneumonia on young pigs.

ISSN:0323-3847    

DOI:10.1002/bimj.4710370503

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractA special class of incomplete contingency tables has structural zeroes in one or more cells. Some of these tables have a triangular appearance in the sense that they are square and their cells are known a priori to contain zeroes above (or below) their main diagonals. We propose methods of analyzing log‐linear models and testing quasi‐independence in these triangular tables. We also offer a method for combining such tables that are stratified by a concomitant categorical variable. This strategy follows the same approach used in a Cochran‐Mantel‐Haensz

ISSN:0323-3847    

DOI:10.1002/bimj.4710370504

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractSatterthwaite's approximation of the distribution of a nonnegative linear combination of independent mean squares is addressed in this article. A measure is developed to quantify the closeness of this approximation by using certain optimization results given by THIBAUDEAU and STYAN (1985). The main advantage of the proposed measure is to provide a theoretical framework for determining conditions under which Satterthwaite's approximation may be inadequate. This is demonstrated in three examples portraying frequently encountered problems in analysis of variance.

ISSN:0323-3847    

DOI:10.1002/bimj.4710370505

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractDiet surveys in the science of human nutrition involve longitudinal observations on the same individuals repeated at distinct time points. Consequently a common feature of such surveys is inherent correlation between successive observations. In this paper, an autoregressive model of order 1 is assumed for the successive observations on the same individual in a survey. Further, observations on the same individual in two different surveys are assumed to be correlated. The technique of analysis of variance is modified suitably for this set up and applied to two nutritional surveys carried on army recruits.

ISSN:0323-3847    

DOI:10.1002/bimj.4710370506

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractDue to staggered entries of patients during a clinical trial, the available exposure to observe the patients under a treatment is less and non‐uniform while the patients with whom the trial is started initially are exposed to uniform exposures to the treatment. Because of this, the true response of the treatment gets masked. Here we have attempted to estimate the true response of the treatment in presence of staggered entries. Further, by Martingale approach the probability of acceptance/rejection has been worked out for both staggered and no staggered entry cases. The results are then compared with the help of a numerical example which shows that under staggered entries the treatment is rejected with higher probabilit

ISSN:0323-3847    

DOI:10.1002/bimj.4710370507

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractThe generalized negative binomial distribution has been found useful in fitting over‐dispersed as well as under‐dispersed count data. We define and study the generalized binomial regression model which is used to predict a count response variable affected by one or more explanatory variables. The methods of maximum likelihood and moments are given for estimating the model parameters. Approximate tests for the adequacy of the model are considered. The generalized binomial regression model has been applied to two observed data sets to which binomial regression model was applied earl

ISSN:0323-3847    

DOI:10.1002/bimj.4710370508

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractA new failure model is introduced in the form of a four‐parameter nonlinear differential equation, with failure probability as the dependent variable and failure time as the independent variable. The first parameter characterizes the location, the second the scale, and the other two the shape of the model. The type of the accompanying hazard function is immediately read off the shape parameters. The new model approximates the classical failure models with rather high precision, but also models cases where the failure density is skewed to the left. It can be used to analyze survival data objectively, based on the shape of the failure distribution. The computation of quantiles and moments is easy and fast. Nonlinear regression methods are used to estimate parameter value

ISSN:0323-3847    

DOI:10.1002/bimj.4710370509

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractTransformation and computer intensive methods such as the jackknife and bootstrap are applied to construct accurate confidence intervals for the ratio of specific occurrence/exposure rates, which are used to compare the mortality (or survival) experience of individuals in two study populations. Monte Carlo simulations are employed to compare the performances of the proposed confidence intervals when sample sizes are small or moderate.

ISSN:0323-3847    

DOI:10.1002/bimj.4710370510

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractThis article considers the asymptotic estimation theory for the log relative potency in a symmetric parallel bioassay when uncertain prior information about the true log relative potency is assumed to be a known quantity. Three classes of point estimation, namely, the unrestricted estimator, the shrinkage restricted estimator and shrinkage preliminary test estimator are proposed. Their asymptotic mean squared errors are derived and compared. The relative dominance picture of the estimators is presented. Interestingly, proposed shrinkage preliminary test estimator dominates the unrestricted estimator in a range that is wider than that of the usual preliminary test estimator. Most importantly, the size of the preliminary test is much appropriate than the usual preliminary test estimator.

ISSN:0323-3847    

DOI:10.1002/bimj.4710370511

出版商:WILEY‐VCH Verlag    

年代:1995

数据来源: WILEY