The item analyzer: a mechanical device for treating the four fold table in large samples

Abstract

This article describes the construction and use of a device for discovering quickly and easily which items differentiate contrasting groups at a given level of probability. The method differs from others in that it requires no computations, only the basic tabulations being needed. "It is applicable directly to all 2 x 2 tables where the smallest expected frequency exceeds 500." For tables in which the smallest expected frequency is between 100 and 500, or when the two contrasted samples are nearly equal, even for tables in which the smallest expected frequency is between 100 and 5, the method is applicable with a slight correction. "The method has been extended to make it applicable to n x r contingency tables." (PsycInfo Database Record (c) 2025 APA, all rights reserved)