Test selection and suppressor variables
A theoretical discussion of the factor pattern of predictor tests and criterion shows that ordinary test selection methods break down under certain circumstances. It is shown that maximal resultsmay not occur if suppressor variables are present among the predictors. Suggested solutions to the problem include: (1) prior item analysis of tests against the criterion, (2) selection of several trial batteries including some with suppressor variables on the basis of a factor analysis of tests and criterion, (3) modification of the usual test selection procedures to include separate solutions based upon each of several starting variables, or (4) the cumbersome and tedious solution of all possible combinations of predictors. The solutions are recommended in the order named above. Although all of the suggested solutions involve added labor and may not be necessary, the test or battery constructor should at least be aware of the problem.
KeywordsPublic Policy Selection Method Statistical Theory Selection Procedure Usual Test
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- 1.McNemar, Q. The mode of operation of suppressant variables.Amer. J. Psychol., 1945,58, 554–555.Google Scholar
- 2.Meehl, P. E. A simple algebraic development of Horst's suppressor variables.Amer. J. Psychol., 1945,58, 550–554.Google Scholar
- 3.Stead, Shartle, et. al. Occupational counseling techniques, Appendix V, pp. 245–252, New York: American Book Co. 1940.Google Scholar
- 4.Toops, H. A. The L-Method.Psychometrika, 1941,6, 249–266.Google Scholar
- 5.Wherry, R. J. and Gaylord, R. H. The concept of test and item reliability in relation to factor pattern.Psychometrika, 1943,8, 247–269.Google Scholar
- 6.Wherry, R. J. and Gaylord, R. H. Test selection with integral gross score weights.Psychometrika, 1946,11, 173–183.Google Scholar