When assets are nominal, noninformative rational expectations equilibria exist.

We consider observable restrictions on asset prices in an exchange economy with general preferences and endowments and an asset structure that may be incomplete. - Asset prices satisfy the martingale property with respect to a class of probability measures; however, generically, not with respect...

When the asset market is incomplete, and assets are traded at an initial contracting period, competitive equilibria may fail to exist. This may occur in a robust economy with asset payoffs denominated in a numeraire commodity. Restrictions on the asset structure guarantee the existence of...