摘要:

AbstractA recursive method of obtaining the maximum likelihood estimates of the parameters of the quadratic logistic discriminant function is presented. This method is an extension of the Walker and Duncan procedure (1967) proposed for the linear logistic discriminant function in a dichotomous case. A generalization of the method to the problem of discrimination between several populations is also given in the paper. It works for both linear and quadratic logistic discriminant function. After an estimation of the parameters of the logistic function a classification can be performed. An example of application of the method to automatic diagnosis of some respiratory diseases is presented. Comparison with the standard procedures used for the estimation is done by a short simulation study.

ISSN:0323-3847    

DOI:10.1002/bimj.4710300302

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractA robust test (to be referred to asM*test) is proposed for testing equality of several group means without assuming normality and equality of variances. This test statistic is obtained by combining Tiku's MML robust procedure with the James statistic. Monte Carlo simulation studies indicate that theM*test is more powerful than the Welch test, the James test, and the tests based on Huber'sM‐estimators over a wide range of nonnormal universes. It is also more powerful than the Brown and Forsythe test under most of nonnormal distributions and has substantially the same power as the Brown and Forsythe test under normal distribution. Comparing with Tan‐Tabatabai test,M*is almost as powerful as Tan‐Tabatabai

ISSN:0323-3847    

DOI:10.1002/bimj.4710300303

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0323-3847    

DOI:10.1002/bimj.4710300304

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractTo test an assumed mean vector, and to test the equality of two mean vectors, robust statistics are developed which have exactly the same form as the HotellingT2statistics. These statistics are shown to have remarkable type I error robustness and power.

ISSN:0323-3847    

DOI:10.1002/bimj.4710300305

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0323-3847    

DOI:10.1002/bimj.4710300306

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractA robust method for selection of variables with the greatest discriminatory power is presented in the paper. The method deals with the two groups of data problem. An application of the method to some respiratory disease data and comparisons with classical procedures are given, also.

ISSN:0323-3847    

DOI:10.1002/bimj.4710300307

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0323-3847    

DOI:10.1002/bimj.4710300308

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractUsing sib‐pairs and parent‐pairs data, a quantitative trait can be tested for the existence of a major locus under the mixed model of Morton and MacLean (1974). The basic idea is to obtain the two conditional likelihoods for sib‐pair differences and parent‐pair differences provided that it is known which sib‐pairs or parent‐pairs have the same effect at the major locus. Two conditions are introduced to obtain two recursive computer algorithms that distinguish the sib‐pairs or parent‐pairs having the same effect at the major locus. This method has the advantage of reducing complicated computations involving maximum likelihood estimates from nuclear families. A simulation experiment is performed to illustrate the method and its result

ISSN:0323-3847    

DOI:10.1002/bimj.4710300309

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractThis paper discusses the need to account for the sampling scheme in an analysis of epidemiological population data which were collected by a two‐stage cluster sample. An example is presented where for validity reasons one should generally account for the sampling scheme, though a rule‐of‐thumb is given to estimate the effect of not doing so. The example concerns one of the centers (Augsburg, F. R. G.) participating in the WHO MONICA Project, which was designed to study the relationship between changes in risk factor levels, as measured by several surveys in each center, and changes in cardiovascular incidence rates, as measured by a registry system for each center. Variance estimation methods which either account for or ignore the sampling scheme are compared for a particular sampling scheme. Easily computable upper bounds on the effect on variances of ignoring the sampling scheme are presented, both over all possible variables, and for a particular var

ISSN:0323-3847    

DOI:10.1002/bimj.4710300310

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractThis paper gives an approximate Bayes procedure for the estimation of the reliability function of a two‐parameter Cauchy distribution using Jeffreys' non‐informative prior with a squared‐error loss function, and with a log‐odds ratio squared‐error loss function. Based on a Monte Carlo simulation study, two such Bayes estimators of the reliability are compared with the maximum likelihood

ISSN:0323-3847    

DOI:10.1002/bimj.4710300311

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY