Exactly forty years after Eugene Fama's (1965) article "The Behavior of Stock Market Prices" (Journal of Business), the play "E?cient Capital Markets" is still going strong. With his thesis, Frank Ecker is adding a new act to the play: His work is a combination of several new developments on the analytical and empirical capital market research front. Capital market e?ciency is based on two aspects. First, the ability of investors to identify a situation in which asset prices are out of the capital market equilibrium. Second, on the possibility of the market to make arbitrage pro?ts by driving...