Dear r-helpers, Prior to analysis of variance, I ran the Boxcox function (MASS library) to find the best power transformation of my data. However, reading the Boxcox help file, I cannot figure out if this function (through its associated log-likelihood function) corrects for * normality only * or if it also induces * homogeneity of variances *. I found in Biometry (Sokal and Rohlf, p. 419) that the box-cox transformation can be extended to induce homogenity of variances in conjunction with Bartlett's test of homogeneity of variances. Does the Boxcox function implemented in R refer to this extension ? Thanks a lot,
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