> What is the positive feedback loop for schools that rank highly on "produces the most improved students"? Would they receive extra government funding? Attract better students? I see neither of these as likely. Try again Mr. Gates.

If nothing else, colleges that are publicly known for effectiveness will have an easier time recruiting and retaining talented employees. They would presumably also be a magnet for results-driven philanthropists, either through direct donations or being somehow accredited for scholarships.