This dissertation studies two important stock market anomalies, the correlation between stock returns and inflation and the predictability of stock returns. Chapter 1 is an introduction. Chapter 2 investigates why the stock return-inflation relation changes over time. Kaul (1987) considers changes in the monetary policy regime, while Hess and Lee (1999) propose changes in the composition of structural shocks. I show in Chapter 2: (1) different from Kaul (1987) and Hess and Lee (1999), both changes in the monetary policy regime and changes in the composition of structural shocks can in principle cause changes in the stock return-inflation relation; (2) empirically, the change in the monetary policy regime is quantitatively more important in ...