School-achievement test: score structure in the set of subjects
Komenda, S.
Acta Universitatis Palackianae Olomucensis Facultatis Medicae 111: 437-447
1985
ISSN/ISBN: 0301-2514 PMID: 2949528 Document Number: 260520
Correct-response score of a subject in the school-achievement test is a sum of two components; the 1st being the number of test items whose topic is known for the subject, the 2nd one being a contribution of random guessing in case of test items unknown for him. In the paper, relations and formulas for the mean value and variance of both these components, together with their covariance and correlation coefficient are derived. All these characteristics depend on the mean value and variance of the correct-response score. Since both these last characteristics are directly accessible and can be thus calculated from the test scalogram, the results obtained in the presented paper make it possible to estimate the statistical characteristics of both test score components in a numerical way.