Browsing by Author "Claudy, John G."

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    Biserial weights: A new approach to test item option weighting
    (1978) Claudy, John G.
    Option weighting is an alternative to increasing test length as a means of improving the reliability of a test. The effects on test reliability of option weighting procedures, including two procedures not previously reported, were compared in two empirical studies using four independent sets of items. In all cases Guttman weights and Biserial weights (based on the Brogden Biserial or Cleman’s Lambda coefficient) were superior to Number Right and Correction for Guessing weights. Overall, Biserial weights appeared to be superior to Guttman weights.
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    Multiple regression and validity estimation in one sample
    (1978) Claudy, John G.
    This study empirically investigated equations for estimating the value of the multiple correlation coefficient in the population underlying a sample and the value of the population validity coefficient of a sample regression equation. In addition to previously published estimation equations, several new procedures, including an empirically derived equation, were evaluated using 16 independent populations. Overall, the empirical equation was superior to any of the previously published estimation procedures. It appears that cross-validation may no longer be necessary for certain purposes.