This essay reviews the family of models that seek to provide aggregate risk based explanations for the empirically observed equity premium. Theories based on non-expected utility preference structures, limited financial market participation, model uncertainty and the small probability of...

In Merton (1987), idiosyncratic risk is priced in equilibrium as a consequence of incomplete diversification. We modify this model to allow the degree of diversification to vary with average idiosyncratic volatility. This simple recognition results in a state-dependent idiosyncratic risk premium...

Targeting readers with backgrounds in economics, Intermediate Financial Theory, Third Edition includes new material on the asset pricing implications of behavioral finance perspectives, recent developments in portfolio choice, derivatives-risk neutral pricing research, and implications of the...