Internal consistency as one rationale for item selection from the universe of possible test items is discussed. Formulae, derived by Lord (1958), are presented which relate the maximum internal consistency of a test to the largest eigenvalue of the interitem correlation matrix. A computationally feasible stepwise procedure is suggested which selects a subset of the original test items that yields maximum internal consistency. The characteristics of a computer program designed to perform these calculations for an input score matrix are described.
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