This paper shows that the VIX market contains information on the variance of the S&P 500 returns, which is not already spanned by the S&P 500 market. We estimate a flexible affine model based on a joint time series of underlying indexes and option prices on both markets. We find that including...

In a tractable stochastic volatility model, we identify the price of the smile as the price of the unspanned risks traded in SPX option markets. The price of the smile reflects two persistent volatility and skewness risks, which imply a downward sloping term structure of low-frequency variance...