The role of significance testing: some data with a message

Abstract

In the context of experimental data, allowance for data-snooping in significance testing is found to conflict with power considerations. Appendices give ( a ) specific results for the nonparametric statistics employed, ( b ) general theorems concerning expected significance level and ( c ) general theorems concerning allowance for data-snooping. In ( b ), a correction is made of a lacuna of Dempster and Schatzoff.