In the U.S., momentum portfolios formed on returns from 12 to seven months prior to the current month deliver higher returns than momentum portfolios formed from six to two months prior, suggesting an “echo” in returns (Novy-Marx (2012)). In 37 countries not including the U.S., there is no...

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

Current R&D expenditures forecast cash-based operating profitability up to three years in the future and sometimes as much as ten years, but do not forecast asset growth. High R&D firms have positive loadings on a cash-based operating profitability factor, and zero alphas. Capitalizing R&D to...