There is a new paper by Ranadeb Chaudhuri, Zoran Ivkovich, Joshua Matthew Pollet, and Charles Trzcinka, the abstact is this:
Several hundred individuals who hold a Ph.D. in economics, finance, or others fields work for institutional money management companies. The gross performance of domestic equity investment products managed by individuals with a Ph.D. (Ph.D. products) is superior to the performance of non-Ph.D. products matched by objective, size, and past performance for one-year returns, Sharpe Ratios, alphas, information ratios, and the manipulation-proof measure MPPM. Fees for Ph.D. products are lower than those for non-Ph.D. products. Investment flows to Ph.D. products substantially exceed the flows to the matched non-Ph.D. products. Ph.D.s’ publications in leading economics and finance journals further enhance the performance gap.