Levin and Subkoviak (1977) contend that experi menters should consider the reliability of their measures when comparing the power of fixed-ef fects completely randomized designs with that of randomized block designs. The two major purposes of this note are (1) to show that under the condi tions specified by Levin and Subkoviak, it is not necessary to consider the reliabilities when compar ing these two designs and (2) to identify certain er rors in the illustrative example used by Levin and Subkoviak.
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