The Societal Benefit of a Financial Transaction Tax

We provide a novel justification for a financial transaction tax for economies where agents face stochastic consumption opportunities. A financial transaction tax makes it more costly for agents to readjust their portfolios of liquid and illiquid assets in response to liquidity shocks, which increase both the demand for and the price of liquid assets. The higher price improves liquidity insurance and welfare for other market participants. We calibrate the model to U.S. data and find that the optimal financial transaction tax is 1.6% and that it reduces the volume of financial trading by 17%

Limited Commitment and the Demand for Money

Understanding money demand is important for our comprehension of macroeconomics and monetary policy. Its instability has made this a challenge. Common explications for the instability are financial regulations and financial innovations that shift the money demand function. We provide a complementary view by showing that a model where borrowers have limited commitment can significantly improve the fit between the theoretical money demand function and the data. Limited commitment can also explain why the ratio of credit to M1 is currently so low, despite that nominal interest rates are at their lowest recorded levels

Money and Nominal Bonds

This paper studies an economy with ex post heterogeneity and nominal bonds in a model a la Lagos and Wright (2005). It is shown that a strictly positive interest rate is a sufficient condition for the allocation with nominal bonds to be welfare-improving. This result comes from protection against the inflation tax

Outside Versus Inside Bonds

When agents are liquidity constrained, two options exist — borrow or sell assets. We compare the welfare properties of these options in two economies: in one, agents can borrow (issue inside bonds) and in the other they can sell government bonds (outside bonds). All transactions are voluntary, implying no taxation or forced redemption of private debt. We show that any allocation in the economy with inside bonds can be replicated in the economy with outside bonds and that the converse is not true. Moreover, under best policies, the allocation with outside bonds strictly Pareto dominates the allocation with inside bonds

Free-Riding on Liquidity

Do financial market participants free-ride on liquidity? To address this question, we construct a dynamic general equilibrium model where agents face idiosyncratic preference and technology shocks. A secondary financial market allows agents to adjust their portfolio of liquid and illiquid assets in response to these shocks. The opportunity to do so reduces the demand for the liquid asset and, hence, its value. The optimal policy response is to restrict (but not eliminate) access to the secondary financial market. The reason for this result is that the portfolio choice exhibits a pecuniary externality: An agent does not take into account that by holding more of the liquid asset, he not only acquires additional insurance but also marginally increases the value of the liquid asset which improves insurance to other market participants