Fernando M. Martin

Debt, Inflation and Central Bank Independence

Increasing the independence of a central bank from political influence, although ex-ante socially beneficial and initially successful in reducing inflation, would ultimately fail to lower inflation permanently. The smaller anticipated policy distortions implemented by a more independent central bank would induce the fiscal authority to decrease current distortions by increasing the deficit. Over time, inflation would increase to accommodate a higher public debt. By contrast, imposing a strict inflation target would lower inflation permanently and insulate the primary deficit from political distortions.

Government Policy in Monetary Economies

I study how the general and specific details of a micro founded monetary framework affect the determination of policy when the government has limited commitment. The conduct of policy depends on the interaction between the incentive to smooth distortions intertemporally and a time-consistency problem. In equilibrium, fiscal and monetary policies are distortionary, but long-run policy is not afflicted by time-consistency problems. Policy variables in specific applications of the general framework react similarly to variations in fundamentals. Nevertheless, resolving certain environment frictions affect long-run policy significantly. The response of government policy to aggregate shocks is qualitatively similar across the studied model variants. However, there are significant quantitative differences in the response of government policy to productivity shocks, mainly due to the idiosyncratic behavior of the money demand. Environments with no trading frictions display the best fit to post-war U.S. data.

Information Disclosure and Exchange Media

When commitment is lacking, intertemporal trade is facilitated with the use of exchange media--interpreted broadly to include monetary and collateral assets. We study the properties of a model commonly used to motivate monetary exchange, extended to include a physical asset whose expected short-run return is subject to a news shock, but whose expected long-run return is stable. The nondisclosure of news enhances the assets property as an exchange medium, and generally improves social welfare. When a nondisclosure policy is infeasible, the framework admits a role for government debt, including fiat money. When lump-sum taxation is not permitted, fiat money may still improve welfare--but only if its circulation is supported by a cash-in-advance constraint. (Copyright: Elsevier)

Rehypothecation and Liquidity

We develop a dynamic general equilibrium monetary model where a shortage of collateral and incomplete markets motivate the formation of credit relationships and the rehypothecation of assets. Rehypothecation improves resource allocation because it permits liquidity to flow where it is most needed. The liquidity benefits associated with rehypothecation are shown to be more important in high-inflation (high interest rate) regimes. Regulations restricting the practice are shown to have very different consequences depending on how they are designed. Assigning collateral to segregated accounts, as prescribed in the Dodd-Frank Act, is generally welfare-reducing. In contrast, an SEC15c3-3 type regulation can improve welfare through the regulatory premium it confers on cash holdings, which are inefficiently low when interest rates and inflation are high.

The Value of Constraints on Discretionary Government Policy

This paper investigates how institutional constraints discipline the behavior of discretionary governments subject to an expenditure bias. The focus is on constraints implemented in actual economies: monetary policy targets, limits on the deficit and debt ceilings. For a variety of aggregate shocks considered, the best policy is to impose a minimum primary surplus of about half a percent of output. Most welfare gains from constraining government behavior during normal times, which to a large extent is sufficient to discipline policy in adverse times. Monetary policy targets are not generally desirable as they hinder the ability of governments to smooth distortions. Allowing for the effective use of inflation during transitions is a key component of good institutional design. Debt ceilings are benign, but always dominated by deficit constraints. More pre-commitment to government actions is ineffective in curbing inefficiently high public expenditure.

Money and Capital as Competing Media of Exchange in a News Economy

Conventional theory suggests that fiat money will have value in capital-poor economies. We demonstrate that fiat money may also have value in capital-rich economies, if the price of capital is excessively volatile. Excess asset-price volatility is generated by news; information that has no social value, but is privately useful in forming forecasts over the short-run return to capital. One advantage of fiat money is that its expected return is not linked directly to news concerning the prospects of an underlying asset. When money and capital compete as media of exchange, excess volatility in the short-term returns of liquid asset portfolios is mitigated and welfare is improved. A legal restriction that prohibits the use of capital as a payment instrument renders the expected return to money perfectly stable and, as a consequence, may generate an additional welfare benefit.

Money, banking and financial markets

The fact that money, banking, and financial markets interact in important ways seems self-evident. The theoretical nature of this interaction, however, has not been fully explored. To this end, we integrate the Diamond (1997) model of banking and financial markets with the Lagos and Wright (2005) dynamic model of monetary exchange?a union that bears a framework in which fractional reserve banks emerge in equilibrium, where bank assets are funded with liabilities made demandable in government money, where the terms of bank deposit contracts are affected by the liquidity insurance available in financial markets, where banks are subject to runs, and where a central bank has a meaningful role to play, both in terms of inflation policy and as a lender of last resort. Among other things, the model provides a rationale for nominal deposit contracts combined with a central bank lender-of-last-resort facility to promote efficient liquidity insurance and a panic-free banking system.

Market Power and Asset Contractibility in Dynamic Insurance Contracts

The authors study the roles of asset contractibility, market power, and rate of return differentials in dynamic insurance when the contracting parties have limited commitment. They define, characterize, and compute Markov-perfect risk-sharing contracts with bargaining. These contracts significantly improve consumption smoothing and welfare relative to self-insurance through savings. Incorporating savings decisions into the contract (asset contractibility) implies sizable gains for both the insurers and the insured. The size and distribution of these gains depend critically on the insurers’ market power. Finally, a rate of return advantage for insurers destroys surplus and is thus harmful to both contracting parties.

Moral Hazard and Lack of Commitment in Dynamic Economies

We revisit the role of limited commitment in a dynamic risk-sharing setting with private information. We show that a Markov-perfect equilibrium, in which agent and insurer cannot commit beyond the current period, and an infinitely-long contract to which only the insurer can commit, implement identical consumption, effort and welfare outcomes. Unlike contracts with full commitment by the insurer, Markov-perfect contracts feature non-trivial and determinate asset dynamics. Numerically, we show that Markov-perfect contracts provide sizable insurance, especially at low asset levels, and are able to explain a significant part of wealth inequality beyond what can be explained by self-insurance. The welfare gains from resolving the commitment friction are larger than those from resolving the moral hazard problem at low asset levels, while the opposite holds for high asset levels.

Policy and Welfare Effects of Within-Period Commitment

I study the implications of different institutional frameworks for the conduct of fiscal policy, under the assumption that the government cannot commit to future policy choices. The environments analyzed vary on whether the government is endowed with the ability to commit to beginning-of-period policy announcements or not. If it cannot, then there are two variants, depending on which actions private agents take before observing the government’s policy choice. How the three possible cases rank in terms of tax rates and welfare varies substantially with the economy’s fundamentals and whether depreciation is tax deductible or not. More generally, I find that regimes with higher tax rates do not necessarily imply lower welfare. I also find that making depreciation not tax-deductible typically involves a welfare loss. Within the context of the environments studied in this paper, I find that there are only small gains from modifying the way fiscal policy is conducted in modern developed economies. Furthermore, some reforms may lead to large welfare losses.