An Analysis of the Verbal Scholastic Aptitude Test Using Birnbaum's Three-Parameter Logistic Model

acteristic curves was first presented by Lawley (1943). Lazarsfeld (1950, 1959) developed a more general theory, mainly in the context of attitude tests and other short questionnaires. Lord (1952, 1953a, 1953b) worked on the theory for aptitude and achievement tests. He reported (1952) some encouraging empirical results, checking for agreement between the mathematical model and actual test data. In 1957-1958 Birnbaum published a series of reports using item-characteristic-curve models. He applied modern theory of statistical inference, answering many outstanding theoretical problems in test construction, scoring of responses, and interpretation of test results.