O’Brien Test for Homogeneity of Variance
نویسنده
چکیده
The homogeneity of variance assumption is one of the critical assumptions underlyingmost parametric statistical procedures such as the analysis of variance and it is important to be able to test this assumption. In addition, showing that several samples do not come from populations with the same variance is sometimes of importance per se. Among the many procedures used to test this assumption, one of the most sensitive is the O’Brien test. This test was developed by O’Brien (1979, 1981). The null hypothesis for this test is that the samples under considerations come from populations with the same variance; The alternative hypothesis is that the populations have different variances. Compared to other tests of homogeneity of variance, the advantage of the O’Brien test resides in its versatility and its compatibility with standard analysis of variance designs (cf. O’Brien, 1979; Martin & Games, 1977; Games, Keselman, & Clinch 1979). It is also optimal because itminimizes both Types I and II errors. The
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