## Sylvain Carré, PhD

### Assistant Professor (Maître de conférences) of Economics

Université Paris-Dauphine

**Contact**

sylvain.carre(at)dauphine.psl.eu

**Research interests**

Banking

FinTech

## Articles

### Under revision

Banks as Liquidity Multipliers, with Damien Klossner : *Revise and Resubmit (round 2), Review of Financial Studies*

We study banks' balance sheet formation in the context of liquidity risk management. Using global games techniques, we derive a *marginal liquidity multiplier*, the size of the deposit base expansion a bank can perform when its liquidity buffer increases by one unit, without changing exposure to liquidity risk. We explain intuitively and prove formally that this multiplier is larger than one, and show that it is key for the characterization of the optimal balance sheet. Our theory has implications for the pricing of liquid securities and explains why banks hoard so many liquid assets whose yield is often lower than the cost of their deposits. It also allows to analyze the role of public liquidity provision: while increasing the supply of liquid assets improves welfare, it can also increase run probability, as banks can respond by issuing more deposits.

### Working papers

Security and Liquidity in Proof-of-Stake DeFi Protocols, with Franck Gabriel.

Smart Proofs via Smart Contracts, with Gabriel, Hongler, Lacerda and Capano.

### Publications

Insider Trading with Penalties, with Pierre Collin-Dufresne and Franck Gabriel : **Journal of Economic Theory (2022)***, *volume 203, pages 1-36.

We consider a Kyle (1985) one-period model where insider trading may be subject to a penalty that is increasing in trade size. We characterize the solution - the equilibrium price and optimal trading strategy - explicitly and establish existence and uniqueness for an arbitrary penalty function for the case of uniformly distributed noise. We use this framework to capture the difference between legal and illegal insider trading, and identify the set of `efficient penalty functions' that would be optimal for a regulator that seeks to minimize expected uninformed traders' losses for a given level of price informativeness. Simple policies consisting of a fixed penalty upon nonzero trades belong to this set and can be used to implement any efficient outcome. Using numerical analysis, we show the robustness of our results to different distributional assumptions.

Disclosures, Rollover Risk, and Debt Runs : **Journal of Banking and Finance**** (2022)**, volume 142, pages 1-18.

How do opacity and disclosure policies impact short-term debt financing costs and the likelihood and cost of debt runs? I construct a dynamic model where debt yields are endogenous and mapped explicitly to the degree of transparency, the regulatory disclosure regime and the state of the economy. Different disclosure policies generate sharp differences in the rich debt and beliefs dynamics that I obtain. Short-term yields may remain low while risk builds up, and a disclosure regime might consistently induce better beliefs but imply larger financing costs. At the policy level, my model predicts that the regulator should commit to disclose except at large levels of opacity.

The Sources of Sovereign Risk, with Daniel Cohen and Sébastien Villemot :** Journal of International Economics (2019)**, volume 118, pages 31-43.

This paper contributes to the literature on sovereign default. We show that the stochastic structure of GDP does matter in order to be able to reproduce the key stylized facts regarding sovereign risk: the smooth part of the GDP process explains the counter-cyclical behavior of the current account and the jump part explains the risk of default. Intuitively, it is too costly for a country to restrain consumption in such a way that it does not default even if a large negative shock happens. The country therefore behaves as if these shocks do not exist, generating high levels of debt and positive default probabilities. By contrast, when shocks are smooth, a country always finds it preferable to slightly reduce consumption when necessary in order to remain away from the default frontier, rather than risking a costly default. This produces a counter-cyclical current account.