Get the same results with bonferroni and LSD

Posted by msherman on Apr 20, 2007; 4:36pm
URL: http://spssx-discussion.165.s1.nabble.com/Get-the-same-results-with-bonferroni-and-LSD-tp1075216.html

Dear List:  I just performed a factorial  (2 x 2)ANOVA (Using GLM) and requested some comparisons of the interaction cell means using LSD.

   /EMMEANS = TABLES(Spirituality_Level*Group) compare(spirituality_level) adj(lsd)

I then repeated the above but changed LSD to Bonferroni

   /EMMEANS = TABLES(Spirituality_Level*Group) compare(spirituality_level) adj(bonferroni)

and got the exact same results. In particular the comparison of two specific means provided in the outcome probability of p = .047. for both LSD and Bonferroni.

Next I decided to alter the factorial and make it into one way with four groups. I now used the ONEWAY procedure and requested post hoc tests of LSD and Bonferroni.  Results for the LSD come out the same as the Factorial with p= .047, while the results of the Bonferroni come out with a p value of .18.  If I ran the Bonferroni test and never ran the LSD within the GLM procedure I would have concluded that I had obtained significance.  Has anyone had this problem before? Is it a bug or is it possible that I am doing something wrong.?

martin sherman