학술논문

Power and sample size for ordered categorical data.
Document Type
Journal Article
Source
Statistical Methods in Medical Research. Jan2003, Vol. 12 Issue 1, p73-84. 12p.
Subject
*STATISTICS
*MEDICAL research
*BIOMETRY
*EXPERIMENTAL design
*REGRESSION analysis
*SAMPLE size (Statistics)
*STATISTICAL models
Language
ISSN
0962-2802
Abstract
We propose a new method for computing power and sample size for linear rank tests of differences between two ordered multinomial populations. The method is flexible in that it is applicable to any general alternative hypothesis and for any choice of rank scores. We show that the method, though asymptotic, closely approximates existing exact methods. At the same time it overcomes the computational limitations of the exact methods. This advantage makes our asymptotic approach more practical for sample size computations at the planning stages of a large study. We illustrate the method with data arising from both proportional and non-proportional odds models in the two ordered multinomial setting. [ABSTRACT FROM AUTHOR]