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Unbiased estimators of ability parameters, of their variance, and of their parallel-forms reliability

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Abstract

Given known item parameters, unbiased estimators are derived i) for an examinee's ability parameterθ and for his proportion-correct true scoreς, ii) for the variances ofθ andς across examinees in the group tested, and iii) for the parallel-forms reliability of the maximum likelihood estimator\(\hat \theta\).

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Reference note

  • Sympson, J. B.Estimating the reliability of adaptive tests from a single test administration. Paper presented at the meeting of the American Educational Research Association, Boston, April 1980.

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This work was supported in part by contract N00014-80-C-0402, project designation NR 150-453 between the Office of Naval Research and Educational Testing Service. Reproduction in whole or in part is permitted for any purpose of the United States Government.

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Lord, F.M. Unbiased estimators of ability parameters, of their variance, and of their parallel-forms reliability. Psychometrika 48, 233–245 (1983). https://doi.org/10.1007/BF02294018

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  • DOI: https://doi.org/10.1007/BF02294018

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