A DEFENSE OF STATISTICAL POWER ANALYSIS

Chow attacks statistical power analysis on theoretical grounds. I argu e that if significance testing is defensible, so is power analysis. A number of Chow's criticisms seem to suggest that power analysts are co nfused about certain fundamental issues. I claim that few power analys ts make the mistakes Chow describes. Finally, I address Chow's claim t hat power analysis is irrelevant to NHSTP because it deals with a diff erent issue.