Seven approaches to averaging reliability coefficients are presented. Each approach starts with a unique definition of the concept of “average,” and no approach is more correct than the others. Six of the approaches are applicable to internal consistency coefficients. The seventh approach is specific to alternate-forms coefficients. Although the approaches generally produce unequal averages, a Monte Carlo study found little difference among the average reliabilities calculated by the first six approaches. The first three approaches may be especially useful for reliability generalization studies.
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