標題: Effect size, statistical power, and sample size for assessing interactions between categorical and continuous variables
作者: Shieh, Gwowen
管理科學系
Department of Management Science
關鍵字: effect sizes;moderation;power analysis;sample size
公開日期: 1-Feb-2019
摘要: The reporting and interpretation of effect size estimates are widely advocated in many academic journals of psychology and related disciplines. However, such concern has not been adequately addressed for analyses involving interactions between categorical and continuous variables. For the purpose of improving current practice, this article presents fundamental features and theoretical developments for the variance of standardized slopes as a desirable standardized effect size measure for the degree of disparity between several slope coefficients. To estimate the effect size, a consistent and nearly unbiased estimator is described and a simple refinement is emphasized for extreme situations whenever appropriate. The essential problems of power and sample size calculations for testing the equality of slope coefficients are also considered. According to the analytic justification and empirical assessment, the exact approach has a clear advantage over the approximate methods. Both SAS and R computer codes are provided to facilitate practical accessibility of the proposed techniques in interaction studies.
URI: http://dx.doi.org/10.1111/bmsp.12147
http://hdl.handle.net/11536/148737
ISSN: 0007-1102
DOI: 10.1111/bmsp.12147
期刊: BRITISH JOURNAL OF MATHEMATICAL & STATISTICAL PSYCHOLOGY
Volume: 72
起始頁: 136
結束頁: 154
Appears in Collections:Articles