Ergo: a New Approach To Multidimensional Item Analysis
Thomas J. Reynolds · Educational and Psychological Measurement · 1981
Cliff (1977) suggests a series of indices, intended for a testing context, that establish a relation between dominance matrices and classical measurement. Cliff's index c derived from an item dominance matrix is utilized in a clustering approach (termed ERGO) to isolate Guttman-type item hierarchies. A comparison of factor analysis to the ERGO is made on social distance data involving multiple ethnic groups. The ERGO procedure surpassed the factor analysis by satisfactorily identifying both the number of hypothetical item hierarchies as well as the developmental order within each hierarchy.