This paper examines how, in the presence of individual risk, economic efficiency can be achieved without an unrealistically large number of contingent markets. The authors show that consistency of beliefs and optimality of allocation can be guaranteed with an appropriate array of Arrow...

We study endogenous uncertainty stemming from the introduction of new financial assets, so as to evaluate the risks as well as the welfare gains of financial innovation. The introduction of financial assets to hedge individual risk can lead to the risk of default, which is a collective risk. The...

In this paper we study the introduction of new assets which are oftenly observed to be defined in expected values rather than state by state, called the Arrow-Lind-Malinvaud (ALM) assets. We demonstrate that individual default emerges naturally in an economy where such ALM assets are introduced...