Céline Rochon

Generic efficiency and collusion-proofness in exchange economies

Abstract. The purpose of this paper is to study the kind of efficient allocations that can be achieved in exchange economies with asymmetric information, by means of a decentralized mechanism robust to coalitional, strategic deviations. To this end, we define a new strategic equilibrium concept – called strong collusion-proof contract – designed to characterize stable communication agreements in games with differential information against non-binding, self-enforcing and incentive compatible deviations by coalitions. We then construct a strategic market mechanism which, for quasi-linear economies, is such that its strong collusion-proof contracts generically induce the incentive compatible interim efficient allocations. Moreover, we show that these allocations can be achieved by strong collusion-proof contracts. We show that the internally consistent extension of the strong collusion-proof contracts generically yields the same set of efficient allocations.

Consistent collusion-proofness and correlation in exchange economies

We present a feasible strategic market mechanism with finitely many agents whose Nash, semi-strong Nash and coalition-proof Nash equilibria fully implement the Walrasian equilibria. We define a strategic equilibrium concept, called correlated semi-strong equilibrium, and show that the Walrasian equilibria can be implemented by these equilibria, and also by the coalition-proof correlated equilibria of our mechanism. We show that these two concepts, suitably modified with transfers, fully implement the Pareto optimal allocations.

A Real Model of Transitional Growth and Competitiveness in China

We present a stylized real model of the Chinese economy with the objective of explaining two features: (1) domestic production is highly competitive in the sense that an accumulation of capital that raises the marginal product of labor elicits increases in employment and output rather than only in wages; and (2) even though the domestic saving rate is high, foreign direct investment is also substantial. We explain these features in terms of a conventional neoclassical growth model -- with no monetary or nominal exchange rate policy -- by including two aspects of the economy explicitly in the model: (1) low production wages are sustained by a large reserve army of rural labor which drives internal migration, and (2) domestic capital is distinct from importable capital and complementary with it in production. The results suggest that underlying real phenomena are important in explaining recent history; while nominal renmimbi appreciation may dampen price and wage increases, it would probably not change the real factors that have sustained rapid growth.

What’s Different about Bank Holding Companies?

The recent fnancial crisis highlighted the role of Bank Holding Companies (BHCs) in exacerbating the crisis and in transmitting monetary policy beyond the local economy to global markets. Yet, little is known about their behavior, as most models of banking typically focus on banks with a loan desk. We develop a dynamic model of a BHC that encompasses both a trading desk and a loan desk, and explore the role of risk attitude and overleveraging by the trading desk. We trace the impact of monetary policy and market innovations on bank behavior in the presence of Basel III type regulations. To our knowledge, this is a first such exercise. We show that the value of the BHC is enhanced by operating both desks, even if they both are subject to common market shocks. We explore alternative regulatory remedies to ongoing efforts to ring-fence the proprietary trading business, and show that regulations that target bank governance can mitigate possible rogue trading and the overleveraging problem.

Optimal Maturity Structure of Sovereign Debt in Situation of Near Default

We study the relationship between default and the maturity structure of the debt portfolio of a Sovereign, under uncertainty. The Sovereign faces a trade-off between a future costly default and a high current fiscal effort. This results into a debt crisis in case a large initial issuance of long term debt is followed by a sequence of negative macro shocks. Prior uncertainty about future fundamentals is then a source of default through its effect on long term interest rates and the optimal debt issuance. Intuitively, the Sovereign chooses a portfolio implying a risk of default because this risk generates a correlation between the future value of long term debt and future fundamentals. Long term debt serves as a hedging instrument against the risk on fundamentals. When expected fundamentals are high, the Sovereign issues a large amount of long term debt, the expected default probability increases, and so does the long term interest rate.

A Real Model of Transitional Growth and Competitiveness in China1

We present a stylized real model of the Chinese economy with the objective of explaining two features: (1) domestic production is highly competitive in the sense that an accumulation of capital that raises the marginal product of labor elicits increases in employment and output rather than only in wages; and (2) even though the domestic saving rate is high, foreign direct investment is also substantial. We explain these features in terms of a conventional neoclassical growth model—with no monetary or nominal exchange rate policy—by including two aspects of the economy explicitly in the model: (1) low production wages are sustained by a large reserve army of rural labor which drives internal migration, and (2) domestic capital is distinct from importable capital and complementary with it in production. The results suggest that underlying real phenomena are important in explaining recent history; while nominal renmimbi appreciation may dampen price and wage increases, it would probably not change the real factors that have sustained rapid growth.