Throughout the social sciences, tests have been used for two primary - and different - purposes: a) to estimate where an examinee is located on an ability/trait continuum (e.g., intelligence tests), or b) to classify an examinee as either above or below a particular point on the ability continuum (e.g., criterion-referenced tests). From a psychometric perspective, the scoring procedure of the test should reflect the purpose for which the test is being used. From a practical perspective, the administration procedure should be as efficient as possible.

The Myers-Briggs Type Indicator (MBTI; Briggs & Myers, 1976) is a personality inventory designed to classify examinees according to four bipolar dimensions. Although the MBTI is quite popular within corporate America, critics have threatened the validity of the MBTI with two seemingly contradictory faults: the test is too unreliable and too long.

The purpose of this study was to examine the degree to which using an item response theory (IRT)