Since I don't claim to be an expert in such matters, I can't comment on the study, but here's someone who did:
"The Fordham Foundation has produced system for rating states’ standards, the validity of which is not at all obvious. The procedures for determining the rankings are unclear and, therefore, difficult to replicate. The qualifications of the "experts" whose expertise was used in some unspecified way is questionable. If the system had some immediately obvious merit, these objections would be of no import. When one looks, however, at the most immediately obvious place for validating the system – the academic performance of the states – one finds absolutely no correlation. States with well received standards score low, states labeled as "irresponsible" because of their "lousy" standards score high. Taking this report seriously could well lead reformers down blind alleys or toward questionable ends."
http://www.uwm.edu/Dept/CERAI/documents/archives/00/cerai-00-07.htmWho's correct? Dang if I know....