Although a great deal of attention has been devoted over a period of years to the estimation of reliability from item statistics, there are still gaps in the mathematical derivation of the Kuder-Richardson results. The main purpose of this paper is to fill some of these gaps, using language consistent with modern probability theory. (Author)

Findings of this study suggest that it is preferable to attempt to control guessing through the use of the reward instruction rather than to attempt to control it using the penalty instruction or to encourage it using the insttruction to guess. (Authors/MB)