The University Wage Premium: Does it Adequately Reward Productivity?
Channel: valeriereified
Date: 14/07/2011

If each additional year of education yields fewer and fewer results in terms of increased productivity, then why are we paying the highest premium for those who take 17 years of schooling over 13?

Also, not for nothin' but a Nobel-Prize Winner does seem to support my argument here:

http://www.nytimes.com/2011/03/07/opinion/07krugman.html