A large literature finds evidence that pricing kernels nonparametrically estimated from option prices and historical returns are not monotonically decreasing in market index returns. We argue that existing estimation methods are inconsistent and propose a new nonparametric estimator of the...

We provide novel evidence supporting the notion that arbitrageurs can contribute to return comovement via ETF arbitrage. Using a large sample of U.S. equity ETF holdings, we document the link between measures of ETF activity and return comovement at both the fund and the stock levels, after...