, Volume 41, Issue 2, pp 219–231 | Cite as

A k-sample significance test for independent alpha coefficients

  • A. Ralph Hakstian
  • Thomas E. Whalen


The earlier two-sample procedure of Feldt [1969] for comparing independent alpha reliability coefficients is extended to the case ofK ≥ 2 independent samples. Details of a normalization of the statistic under consideration are presented, leading to computational procedures for the overallK-group significance test and accompanying multiple comparisons. Results based on computer simulation methods are presented, demonstrating that the procedures control Type I error adequately. The results of a power comparison of the case ofK=2 with Feldt's [1969]F test are also presented. The differences in power were negligible. Some final observations, along with suggestions for further research, are noted.

Key words

reliability internal consistency comparison of reliability coefficients 


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Copyright information

© Psychometric Society 1976

Authors and Affiliations

  • A. Ralph Hakstian
    • 1
  • Thomas E. Whalen
    • 1
  1. 1.Department of PsychologyUniversity of British ColumbiaVancouverCanada

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