We propose a novel economic mechanism that generates stock return predictability in both the time series and the cross-section. Investors' income has two sources, wages and dividends that grow stochastically over time. As a consequence the fraction of total income produced by wages fluctuates depending on economic conditions. We show that the risk premium that investors require to hold stocks varies with these fluctuations. A regression of stock returns on lagged values of the labor income to consumption ratio produces statistically significant coefficients and large adjusted R2s. Tests of the model's cross-sectional predictions on the set of 25 Fama-French portfolios sorted on size and book-to-market are also met with considerable support.

We propose a novel economic mechanism that generates stock return predictability in both the time series and the cross-section. Investors’ income has two sources, wages and dividends that grow stochastically over time. As a consequence the fraction of total income produced by wages fluctuates depending on economic conditions. We show that the risk premium that investors require to hold stocks varies with these fluctuations. A regression of stock returns on lagged values of the labor income to consumption ratio produces statistically significant coefficients and large adjusted R2s. Tests of the model’s cross-sectional predictions on the set of 25 Fama–French portfolios sorted on size and book-to-market are also met with considerable support.

A common practice in the finance literature is to create characteristic portfolios by sorting on characteristics associated with average returns. We show that the resultant portfolios are likely to capture not only the priced risk associated with the characteristic but also unpriced risk. We develop a procedure to remove this unpriced risk using covariance information estimated from past returns. We apply our methodology to the five Fama-French characteristic portfolios. The squared Sharpe ratio of the optimal combination of the resultant characteristic-efficient portfolios is 2.13, compared with 1.17 for the original characteristic portfolios.

We propose an incentive-based theory of how a savings glut produces financial fragility. Originators must be incentivized to produce high-quality assets. Assets are distributed to informed intermediaries or uninformed investors. A savings glut reduces origination incentives by compressing spreads between the prices paid for high-quality assets by informed intermediaries and prices paid by uninformed investors for generic assets. The narrowing of spreads relaxes intermediaries’ borrowing constraints, resulting in higher leverage. This generates financial fragility: intermediaries are more likely to become insolvent if unforeseen losses arise. Our model offers a coherent narrative of the run-up to the Global Financial Crisis.