Welch-James Statistic for Robust Hypothesis Testing under Heterocedasticity and Non-Normality
Children's reaction times (milliseconds) to stimuli of different natur...
Confidence interval for the effect size of model effects
Summarizing Welch Approximate Degrees of Freedom test results
General Approximate Degrees of Freedom Solution for Inference and Esti...
Implementation of Johansen's general formulation of Welch-James's statistic with Approximate Degrees of Freedom, which makes it suitable for testing any linear hypothesis concerning cell means in univariate and multivariate mixed model designs when the data pose non-normality and non-homogeneous variance. Some improvements, namely trimmed means and Winsorized variances, and bootstrapping for calculating an empirical critical value, have been added to the classical formulation. The code departs from a previous SAS implementation by L.M. Lix and H.J. Keselman, available at <http://supp.apa.org/psycarticles/supplemental/met_13_2_110/SAS_Program.pdf> and published in Keselman, H.J., Wilcox, R.R., and Lix, L.M. (2003) <DOI:10.1111/1469-8986.00060>.