Financial Stability and the Macroeconomy

The financial crisis of 2007-2009 drew attention to the essential role of banks for the macroeconomy and to the importance of having a resilient financial sector. A vulnerability in the financial sector spills over to the real economy and can drive it into a deep recession. Following the financial crisis, policy makers have issued rules and regulations aimed at strengthening the banks. My dissertation considers some of those measures, namely bank liquidity regulation and deposit insurance, and tries to assess their effectiveness in stabilizing the financial sector and the economy in general.

The first chapter (joint with Prof. Luisa Lambertini) develops a model with regulated banks and a hedge fund to analyze the behavior of wholesale funding and the macroeconomic consequences of liquidity regulation. Banks raise deposits and subordinated wholesale funding from the hedge fund. Wholesale funding amplifies shocks: it is curtailed in economic downturns to avoid leveraging up and risk-taking by banks, further depressing credit and economic activity. By making banks safer, liquidity regulation increases wholesale funding and bank loans at the steady state. However, flat liquidity regulation requiring banks to hold a constant fraction of liquid assets can have unintended consequences and increase macroeconomic volatility. Our model further shows that cyclically adjusted regulation stabilizes the response of the economy to shocks. We also provide empirical evidence suggesting that liquidity helps contain the contraction in wholesale funding and loans during times of funding stress.

The second chapter explores the macroeconomic and welfare implications of harmonizing or joining deposit insurance in the Eurozone. I develop a two-country model to represent the core and periphery countries in the Eurozone. The model features fragile banks that can be subject to endogenous and costly runs. The two countries are financially integrated through an international interbank market. I introduce deposit insurance and compare different insurance regimes in steady state and along the business cycle. The model emphasizes that financial integration implies co-movement in asset prices and the transmission of shocks across the border. I find that when deposit insurance has lower coverage in the periphery than in the core, financial stability is undermined in both regions due to higher asset price volatility and a higher probability of deposit runs. Hence, either harmonizing or joining deposit insurance leads to substantial welfare benefits for both countries.

In the third chapter, I develop a macroeconomic model with multiple equilibria and bank runs to analyze deposit insurance. A bank run is a sunspot equilibrium, and it is caused by a self-fulfilling panic of all depositors. The model features a unique no-run equilibrium when macroeconomic conditions are good, but an unexpected negative shock may open up the possibility of a run equilibrium. A bank run is a rare but costly event that drives the economy in a long and severe recession. I analyze the introduction and build-up of a deposit insurance fund and show that it reduces the cost and probability of bank runs. The dynamic simulation of the model reveals that deposit insurance diminishes macroeconomic and financial instability following a technological shock.

Financial Frictions within the Macroeconomy

Victoria Nuguer

Financial factors are central to the recent economic crisis. Most macroeconomic models treat banks and financial intermediation as a veil. These models are unable to account for the recent financial crisis and they cannot be used for policy evaluation. Financial frictions include default on mortgages, disruptions in financial intermediation, and informational asymmetries, among others. In my dissertation, I propose to analyze the effects of policy in economic models characterized by financial frictions. The thesis is composed of three chapters. The first chapter is joint work with Luisa Lambertini and Pinar Uysal. We explicitly model the housing sector, mortgages, and endogenous default as well as nominal and real rigidities in a dynamic stochastic general equilibrium (DSGE) setting. We use U.S. data for the period 1981-2006 to estimate our model using Bayesian techniques. Our starting point is to have an empirically plausible model with endogenous default in mortgages that can explain the main features of the macroeconomic time series. We analyze how an increase in the mortgage default rate can spread to the rest of the economy and result in a recession. Next we examine different policy options that might mitigate the effects of an increase in the mortgage default rate. In the second chapter I develop a two-country DSGE model with global banks (financial intermediaries in one country lend to banks in the other country). Banks are financially constrained on how much they can borrow from households. The main goal is to obtain a framework that captures the international transmission of a financial crisis through the balance sheet of the global banks as well as to explain the insurance mechanism of the international asset market. A negative shock to the value of the capital in one country generates a global financial crisis through the international interbank market. The third chapter uses the above model to analyze the policy challenges that global banks face. In this chapter, I look at how different unconventional unilateral credit policies help to mitigate the effects of a financial disruption. First, the policies are carried out only by the policy maker of the country directly hit by the shock. Consumers of the country where the intervention and the shock take place are better off with policy than without it; consumers from the other country are worse off. Second, I allow for both policy makers to intervene. Both countries intervening help to reduce the negative effects of the country that is not directly hit by the shock but the intervention is not a Pareto improvement.

EPFL2014

Three Problems of Liquidity under Asymmetric Information

Sylvain Jean Pascal Carré

This thesis develops models for three problems of liquidity under asymmetric information. In the chapter "Disclosures, Rollover Risk, and Debt Runs" I build a model of dynamic debt runs without perfect information in order to understand the impact of asset opacity and disclosure policies on run likelihood and economic efficiency. I find that opacity is desirable with respect to both these metrics if and only if fundamentals are strong enough; and that a bank should commit to disclose truthfully any information it has unless the level of opacity is large. The model also uncovers rich interactions between debt dynamics, beliefs dynamics and equilibrium outcomes: short-term yields may remain low while risk builds up in the background, and therefore may not contain a warning sign of an upcoming crisis; and a disclosure regime might produce higher beliefs about collateral quality but nevertheless imply larger financing costs and thus lead to a bank failure. In the chapter "Short-term Bank Leverage and the Value of Liquid Reserves", we extend the modelling toolbox of the global games literature by providing a fully rational setup where liquid reserves are modeled explicitly. The banks' balance sheet decisions and the prices of all securities are endogenous in the model. A bank possesses two instruments to manage illiquidity risk: its funding policy and the size of its liquid asset holdings,modeled as government bonds. Higher short-term indebtness allows the bank to better capture the liquidity benefits priced into deposits but increases illiquidity risk. Holding more bonds makes the bank more robust to withdrawals but it reduces the bank's asset returns. The impact of an increase in bond supply on bank leverage depends on the general-equilibrium change in the cost of absorbing the supply. The model also illustrates how considering an endogenous leverage decision is key to predict the impact of the economic environment on the liquidity premium. In the chapter "Insider Trading under Penalties", we establish existence and uniqueness of equilibrium in a generalised one-period Kyle (1985)model where insider trades can be subject to a size-dependent penalty. The result is obtained by considering uniform instead of Gaussian noise and holds for virtually any penalty function. We apply this result to regulation issues. We show that the penalty functions maximising price informativeness for given noise traders' losses eliminate small rather than large trades. We generalise this result to cases where a budget constraint distorts the set of penalties available to the regulator.

EPFL2019

Three Essays in Banking and Finance

Damien Olivier Klossner

This thesis develops three models that study the motivation of various agents to take on debt, and the impact that excessive financial leverage can have on social welfare. In the chapter "Short-term Bank Leverage and the Value of Liquid Reserves", the incentive of a bank to take on leverage stems from the fact that its short-term debt provides liquidity benefits to depositors, at the cost of exposing the bank to the risk of runs. In the model, a bank possesses two instruments to manage the risk of runs: its funding policy and the size of its liquid asset holdings, modeled as government bonds. Issuing more debt allows the bank to better capture the liquidity benefits fits priced into deposits but increases illiquidity risk. Holding more bonds makes the bank more robust to withdrawals but it reduces the bank's asset returns. When the supply is scarce, banks are the natural buyers of government bonds. This links the liquidity premium priced into government bonds to the risk of bank runs. In the chapter "Liquidity, Debt Overhang, and Monetary Policy", firms take on bank credit to relax their liquidity constraint and purchase new capital. But taking on debt creates a debt overhang distortion which causes entrepreneurs to pass on protable projects. In the model, entrepreneurs arrange for their financing before they observe the profitability of their investment opportunity. After the latter becomes known, entrepreneurs are liquidity-constrained when investment conditions are favorable, and over-indebted when they are unfavorable. The monetary authority can generate welfare gains by lowering the cost of holding liquidity and, when debt is contracted in nominal terms, by pursuing a counter-cyclical monetary policy. In the chapter "Safe Claim Production and Capital Structure", firms issue debt to satisfy the demand of risk-averse investors for safe claims, at the cost of increasing default risk. In general equilibrium, firms need to be compensated for this service, which can only occur if their debt and equity claims are held and priced by different investor types. This segmentation of the investor base can be sufficient to prevent the existence of a symmetric equilibrium. Instead, only a fraction of firms opt for levered capital structures, and the gain in value obtained by tranching cash flows into debt and equity is offset by the expected cost of default. Changes in aggregate leverage can be divided into variations in extensive (the fraction of levered firms ) and intensive (the leverage ratio of levered firms ) margins. Changes in rm business risk have opposite effects on leverage, depending on whether the risk is of a systematic nature or firm-specific nature.

EPFL2019

Three Problems of Liquidity under Asymmetric Information

Sylvain Jean Pascal Carré

EPFL2019

Three Essays in Banking and Finance

Damien Olivier Klossner

EPFL2019

Financial Frictions within the Macroeconomy

Victoria Nuguer

EPFL2014