David Weiss

David J. Weiss is widely recognized as one of the founders of computerized adaptive testing (CAT) and for directing the development of instruments to assess work adjustment. He earned his B.A. in psychology from the University of Pennsylvania in 1959 and his Ph.D. from the University of Minnesota in 1963. He has spent his entire professional career in the Psychology Department at Minnesota, where he founded and directs the Psychometric Methods Program.

The Theory of Work Adjustment

Though the origination of the theory of work adjustment in 1964 is credited to Rene Dawis and Lloyd Lofquist, Weiss became an important part of the development group in 1964. He coauthored the first major revision of the theory in 1968 and directed the program of research that resulted in the development and validation of the major instruments used to make the theory operational. Weiss was instrumental in developing the Minnesota Ability Test Battery, the Minnesota Satisfactoriness Scales, the Minnesota Importance Questionnaire, and the Minnesota Job Description Questionnaire (MJDQ). For the last 40 years these instruments have been used extensively in vocational psychology research and practice.

Computerized Adaptive Testing

Weiss’s most significant contributions have been as a founder of computerized adaptive testing. Conventional tests of ability and achievement require that each examinee receive the same set of items, and the tests calculate a score based on the number correct responses for that item set. These tests are inefficient because people above or below the average ability level receive a set of items that is too easy (in the former case) or too difficult. In neither case do these items provide any new information about the person’s ability level. Furthermore, items that are too easy can cause boredom and reduce motivation, while items that are too difficult can be highly discouraging to an examinee.

The development of computers and a theoretical model called item response theory enabled Weiss and others to pioneer computerized adaptive testing, a procedure in which the computer administers items that are tailored to each individual’s performance level. After an item is administered, the computer estimates the person’s ability score and selects as the next item the single item that will provide the most additional information about the person’s ability. CAT makes it possible to administer fewer items to a given examine, to specify the desired precision of measurement, and to ensure that examinees receive a set of items that is neither too easy nor too difficult.

Weiss developed several major strategies of adaptive testing, and his research program laid the groundwork for future adaptive testing research. CAT is now used with major aptitude tests such as the Graduate Record Examination, and the Armed Services Vocational Aptitude Battery, with achievement testing in the schools, and in testing for licensure examinations in such fields as nursing. Currently, Weiss and other leading researchers are studying the use of CAT in measuring attitudes, interests, and personality.

Other Accomplishments

Weiss has also written many articles on the use of multivariate statistical procedures (e.g., factor analysis and cluster analysis) in counseling psychology research. He served as associate editor and acting coeditor of the Journal of Counseling Psychology, and he founded and edited Applied Psychological Measurement. He received the Career Achievement Award from the Association of Test Publishers.


  1. Dawis, R. V. (2005). The Minnesota Theory of Work Adjustment. In S. D. Brown & R. W. Lent (Eds.), Career development and counseling: Putting theory and research to work (pp. 3-21). New York: Wiley.
  2. Weiss, D. J. (1970). Research methodology: Factor analysis and counseling psychology Research. Journal of Counseling Psychology, 17, 477-185.
  3. Weiss, D. J. (1995). Improving individual differences measurement with item response theory and computerized adaptive testing. In D. Lubinski & R. V. Dawis (Eds.), Assessing individual differences in human behavior (pp. 49-79). Palo Alto, CA: Davies Black.
  4. Weiss, D. J. (2004). Computerized adaptive testing for effective and efficient measurement in counseling and education. Measurement and Evaluation in Counseling and Development, 37, 70-84.

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