The phi coefficient and chi square as indices of item validity J. P. Guilford OriginalPaper Pages: 11 - 19
The application of Sheppard's correction for grouping George A. Ferguson OriginalPaper Pages: 21 - 27
Note on the mathematical theory of interaction of social classes N. Rashevsky OriginalPaper Pages: 43 - 47
A machine method for computing the biserial correlation coefficient in item validation Elmer B. Royer OriginalPaper Pages: 55 - 59