"Two policies toward payments-system risk are common, but superficially appear to be contradictory. One policy is to restrict the exposure to risk generated by one participant to other participants who are, by one measure or another, directly concerned with the risky participant. The other...

We investigate consequences of ambiguity on efficient allocations in an exchange economy. Ambiguity is embodied in the model uncertainty perceived by the consumers: they are unsure what would be the appropriate probability measure to apply to evaluate consumption and keep in consideration a set...