摘要:

AbstractThe problem of testing the equality of means of two normal populations is considered when independent random samples of random sizes are given with the total number of observations from both populations being a fixed number. An application in forestry is discussed.

ISSN:0323-3847    

DOI:10.1002/bimj.4710330702

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

ISSN:0323-3847    

DOI:10.1002/bimj.4710330703

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

AbstractTwo measures of reliability for nominal scales are compared: Coefficient Kappa andkn, a modification suggested for agreement matrices with free marginals. It is illustrated that the evaluation of two rater's agreement may come to a contradictory conclusion, depending on whetherkorknis used. On the basis of the underlying chance models it is concluded thatkandkncannot be interpreted in the same manner. Specifically when raters disagree, the two measures can be widely discrepant.

ISSN:0323-3847    

DOI:10.1002/bimj.4710330704

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

ISSN:0323-3847    

DOI:10.1002/bimj.4710330705

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

AbstractIn this paper we use the sensitivity curves of TUKEY (1977) and the change of decision point (cdp) (a modified version of the breakdown point of YLVISAKER, 1977), supplemented by simulation studies to acquire knowledge about sensitivity in generalized Wilcoxon rank test statistics. Sensitivity depends on balanced or unbalanced sample size cases, censoring, combinations of failure distributions and sources of errors in the data. It is important to consider the quality of the data, and the results show that cdp and some properties of the sensitivity curves may serve as a hint when selecting a test statistic and when making a decision for a given test statistic.

ISSN:0323-3847    

DOI:10.1002/bimj.4710330706

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

AbstractThis paper deals with the analysis of ordinal data by means of a threshold model. Maximum likelihood estimation is discussed and two examples are used to illustrate the methods.

ISSN:0323-3847    

DOI:10.1002/bimj.4710330707

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

ISSN:0323-3847    

DOI:10.1002/bimj.4710330708

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

AbstractClinical trials research is mainly conducted for the purpose of evaluating the relative efficacy of two or more treatments. However, a positive response due to treatment is not sufficient to put forward a new product because one must also demonstrate safety. In such cases, clinical trials which show a positive effect would need to accrue enough patients to also demonstrate that the new treatment is safe. It is our purpose to show how the efficacy and safety problems can be combined to yield a more practical clinical trial design. In this paper we propose an asymmetric stopping rule which allows the experimenter to terminate a clinical trial early for a sufficiently negative result and to continue to a specified number of patients otherwise. As it turns out, a few interim tests will have negligible effects on the overall significance level.

ISSN:0323-3847    

DOI:10.1002/bimj.4710330709

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

ISSN:0323-3847    

DOI:10.1002/bimj.4710330710

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

AbstractGiven a sample, the problem of choosing one of a variety of theoretical distributions for data analysis has been a major concern to both theoretical and applied statisticians. On the basis of a graph drawn using a normal characterization, a method is given to detect departure from normality. Special mathematical study is presented for the proposed graphs. Tukey'sgandhfamily of distributions are used as an alternate to normality.

ISSN:0323-3847    

DOI:10.1002/bimj.4710330711

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY