================================================================== The gateway between this list and the sci.stat.edu newsgroup will be disabled on June 9. This list will be discontinued on June 21. Subscribe to the new list EDSTAT-L at Penn State using the web interface at http://lists.psu.edu/archives/edstat-l.html. ================================================================== .
So you have something like a gender (2-levels) by practice (3 or more levels) factorial ANOVA and you want to know if the gender main effect is equivilent to the two-group t-test for gender only. Is this correct? If so the answer is no--the two tests are not equivilent. The practice effect and the practice x gender interaction have futher divided the t-test error term into variance associate with practice, variance associated with practice x gender and error. This new error term is unlikely to be identical to the one-way (t-test) error term. In this case you could get very different results from the two statistical tests. Michael **************************************************** Michael Granaas [EMAIL PROTECTED] Assoc. Prof. Phone: 605 677 5295 Dept. of Psychology FAX: 605 677 3195 University of South Dakota 414 E. Clark St. Vermillion, SD 57069 ***************************************************** ----- Original Message ----- From: Gang Chen <[EMAIL PROTECTED]> Date: Thursday, June 10, 2004 4:34 pm Subject: [edstat] Follow-up: Unpaired t test and one-way ANOVA > Thank Dennis, Jim, Donald, and Jay for the quick feedback > regarding my confusion between unpaired t test and one-way ANOVA. > > Yes, my previous 'close look' was not close enough: A little > further algebraic operation does show that the F test for the > significance of the factor effect should be equivalent to the t > test for the difference between the two factor level means. > > Now I have another question: In N-way ANOVA, does the above > conclusion hold as well? Among the N factors there is one factor A > that has two levels: would the F test for the significance of > factor A be equivalent to the t test (two-sided) for the > difference between the two factor level means? I feel it should, > but want to confirm it. > > Thanks again, > Gang Chen
