A nonparametric test for the Behrens-Fisher problem that is an extension of a test proposed by Fligner and Policello was developed. Empirical level and power estimates of this test are compared to those of alternative nonparametric and parametric tests through simulations. The results of our test were better than or comparable to all tests considered.
Hyslop, Terry and Lupinacci, Paul J.
"A Nonparametric Fitted Test For The Behrens-Fisher Problem,"
Journal of Modern Applied Statistical Methods: Vol. 2
, Article 14.
Available at: http://digitalcommons.wayne.edu/jmasm/vol2/iss2/14