We report strong evidence that changes of momentum, i.e. "acceleration", defined as the first difference of successive … returns, provide better performance and higher explanatory power than momentum. The corresponding Γ-factor explains the … momentum-sorted portfolios entirely but not the reverse. Thus, momentum can be considered an imperfect proxy for acceleration …

model yields testable implications for the relations between stock returns, fund returns, fund fees, fund size, and …

theory. Data from other countries are examined to see which features of the U.S. experience apply more generally. The chapter …