Features of a probabilistic testing system that has been implemented on the "cerl" PLATO computer system are described. The key feature of the system is the manner in which an examinee responds to each test item; the examinee distributes probabilities among the alternatives of each item by positioning a small square on or within an…

Procedures for computing content validity and consistency reliability coefficients and determining the statistical significance of these coefficients are described. Procedures employing the multinomial probability distribution for small samples and normal curve probability estimates for large samples, can be used where judgments are made on…