Determining the Minimum Reliability Standard Based on a Decision Criterion

The .70 and .80 reliability standards, proposed by Jum Nunnally, are widely employed across a spectrum of research domains. Nonetheless, due to their arbitrary nature, both standards fail to satisfy the needs of researchers. This paper presents a set of formulas that can be used to compute minimum reliability standards as a function of a decision criterion (margin of error). An example based on a study of preliteracy is considered, for which a two-facet generalizability theory design was employed to estimate a g-coefficient. The minimum reliability standard was used to determine whether the decision criterion was satisfied by the observed reliability coefficient.