<p>gadad and bennyblanco,
I think you make an excellent observation about test-taking patterns in the South. A few states (FL, GA, SC) take the SAT in large numbers but their results are decidedly lower than the other states. Generally, if you go through each region, the states that tended to have the highest scores also had comparatively fewer test takers. I did weight the regional and natinoal results so they are accurate for all of the regions, but that nuance would be easy to miss.</p>
<p>danas,
I think you are right in your comment about the role that State Us play in most of non-Northeastern regions. However, the privates in those areas clearly score lower than the Northeastern schools on the PA measure.</p>