Avoid the Bates Statistics Graduates

Illuminaria's Voice and Number 2 Pencil find a study about Bates College students doing equally well whether or not they submitted their SAT scores. However, as Illuminaria points out, "91% of the submitters participated, but only 68% of the non-submitters participated." This creates all kinds of self-selection problems which basically leaves the study meaningless, because the sample doesn't neccesarily represent the popultion it is purported to.