This paper studies an overlapping generations model with stochastic production and incomplete markets to assess whether the introduction of an unfunded social security system leads to a Pareto improvement. When returns to capital and wages are imperfectly correlated a system that endows retired...

It is known that the incompleteness of asset markets causes inefficiency in almost every equilibrium. Yet unexplored is the ”size” of this inefficiency. The size of a Pareto improvement is the total willingness to pay for it, out of current consumption. Inefficiency is the maximum size of...

I study the welfare implications of size-dependent firm regulation policies (SDPs) in the presence of entrepreneurial risks. Although SDP has been considered a source of misallocation, I show that, once entrepreneurial risks are taken into account, SDP can improve efficiency. Quantitatively, I...

In this paper I use a multi-period OLG model to study how a demographic shock is distributed among different generations. In particular, I investigate whether a funded pension system allows for a smoother adjustment than an unfunded system. The results suggest that the answer to this question...

This paper analyses whether the severe demographic change in Germany causes its high current account surpluses. An ageing population both increases the supply and lowers demand of capital in an economy. Due to a longer life span individuals save more. Fewer workers reduce the optimal capital...

Classic models of fire-sales that emphasize liquidity-constrained natural buyers can-notfully account for the asset fire-sales during the Financial Crisis of 2008. I present a modelto demonstrate that fire-sales may happen even when there is a sizable pool of naturalbuyers and in the absence of...

It is challenging to explain the collapse in the price of subprime mortgage-backed securities (MBS) during the Financial Crisis of 2008, using the existing models of fire-sale. I present amodel to demonstrate that fire-sales may happen evenwhen there is a relatively sizable pool of natural...

This paper compares four forms of inter-regional financial risk sharing: (i) segmentation, (ii) integration trough the secured interbank market, (iii) integration trough the unsecured interbank market, (iv) integration of retail markets. The secured interbank market is an optimal risk-sharing...

This paper argues that the introduction of a short-sale constraint in the Arrow-Radner frameworkinvalidates standard definitions of complete and incomplete markets. In this constrained set-up,two threshold values with familiar properties arise.The case of a zero short-sale bound set on some...

A classic characterization of competitive equilibria views them as feasible allocations maximizing a weighted sum of utilities. It has been applied to establish fundamental properties of the equilibrium notion, such as existence, determinacy, and computability. However, it fails for economies...