, Volume 34, Issue 3, pp 259–299 | Cite as

Estimating true-score distributions in psychological testing (an empirical bayes estimation problem)

  • Frederic M. Lord


The following problem is considered: Given that the frequency distribution of the errors of measurement is known, determine or estimate the distribution of true scores from the distribution of observed scores for a group of examinees. Typically this problem does not have a unique solution. However, if the true-score distribution is “smooth,” then any two smooth solutions to the problem will differ little from each other. Methods for finding smooth solutions are developed a) for a population and b) for a sample of examinees. The results of a number of tryouts on actual test data are summarized.


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Copyright information

© Psychometric Society 1969

Authors and Affiliations

  • Frederic M. Lord
    • 1
  1. 1.Educational Testing ServiceUSA

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