An intertemporal CAPM with stochastic volatility

This paper extends the approximate closed-form intertemporal capital asset pricing model of Campbell (1993) to allow for stochastic volatility. The return on the aggregate stock market is modeled as one element of a vector autoregressive (VAR) system, and the volatility of all shocks to the VAR is another element of the system. The paper presents evidence that growth stocks underperform value stocks because they hedge two types of deterioration in investment opportunities: declining expected stock returns, and increasing volatility.