law of one price, and is present in all but risk-neutral economies. We test the cross-sectional predictions of our theory … equity than for assets, and stronger for more levered firms — consistent with the theory. We test also the timeseries … implications of the theory. Time variation in asset ivol causes time variation in the option value of equity that translates into …

reduction (self-protection) so that correlation becomes endogenous. If prevention concerns only one risk, introducing a second … exogenous risk increases the level of prevention expenditures, even if correlation is negative. If prevention expenditures may …