Is interindexer consistency a hobgoblin?

Abstract It is often assumed that the amount of interindexer consistency experienced under a given method of indexing is somehow indicative of the quality of the indexing. To explore this assumption, two hypotheses are stated concerning the possible connection between interindexer consistency and indexing quality. A specific counter‐example is then exhibited which shows both hypotheses to be invalid. Although a mathematical analysis of the counterexample yields certain insights, the general relationship between interindexer consistency and successful retrieval is more subtle than might have been expected. It is concluded that until equations describing this relationship have been derived, measurements of interindexer consistency will have little meaning as clues to indexing quality.