Alexandros P. Vardoulakis

Capital Regulation in a Macroeconomic Model with Three Layers of Default

We develop a dynamic general equilibrium model for the positive and normative analysis of macroprudential policies. Optimizing financial intermediaries allocate their scarce net worth together with funds raised from saving households across two lending activities, mortgage and corporate lending. For all borrowers (households, firms, and banks) external financing takes the form of debt which is subject to default risk. This “3D model” shows the interplay between three interconnected net worth channels that cause financial amplification and the distortions due to deposit insurance. We apply it to the analysis of capital regulation.

Financial Regulation in General Equilibrium

This paper explores how different types of financial regulation could combat many of the phenomena that were observed in the financial crisis of 2007 to 2009. The primary contribution is the introduction of a model that includes both a banking system and a “shadow banking system” that each help households finance their expenditures. Households sometimes choose to default on their loans, and when they do this triggers forced selling by the shadow banks. Because the forced selling comes when net worth of potential buyers is low, the ensuing price dynamics can be described as a fire sale. The proposed framework can assess five different policy options that officials have advocated for combating defaults, credit crunches and fire sales, namely: limits on loan to value ratios, capital requirements for banks, liquidity coverage ratios for banks, dynamic loan loss provisioning for banks, and margin requirements on repurchase agreements used by shadow banks. The paper aims to develop some general intuition about the interactions between the tools and to determine whether they act as complements and substitutes.

How Does Macroprudential Regulation Change Bank Credit Supply

In the paper we have assumed that the probability of a bank-run, q, is a decreasing function of q LIQ1+x I D R (1+r D ) . The purpose of the online appendix is to present the microfoundations that justify our assumption. We follow the of Goldstein and Pauzner (2005) who apply the global game techniques of Carlsson and van Damme (1993) and Morris and Shin (1998) in bank-run models. Section 1 derives q, while section 2 discusses existence and uniqueness. We show how our framework satisfies the assumptions underlying the existence and uniqueness of a threshold equilibrium, and refer the reader to the aforementioned papers for details.

Debt deflation effects of monetary policy

We assess the role that monetary policy plays in the decision to default using a General Equilibrium model with collateralized loans, trade in fiat money and production. The monetary authority extends long-term credit against risky collateral along with its traditional monetary operations. The value of collateral depends on traditional monetary policy and agents can optimally choose to default depending on the relative value of the collateral to the face value of the loan. Default results in foreclosure, higher borrowing costs, inefficient investment and a decrease in total output. We show that pre-crisis contractionary monetary policy interacts with Fisherian debt-deflation dynamics and can increase the probability that a crisis occurs.

Principles for Macroprudential Regulation

The drafting of macroprudential regulation is largely being driven by the need by policy makers to meet timetables that have been agreed. The legislative drive is taking place without any clear theoretical framework to organise the objectives. In this article we propose two principles that any satisfactory framework ought to respect and then describe one specific model that embodies these principles. We explain the insights from this approach for regulatory design.

Optimal Bank Regulation in the Presence of Credit and Run Risk

We modify the Diamond and Dybvig (1983) model of banking to jointly study various regulations in the presence of credit and run risk. Banks choose between liquid and illiquid assets on the asset side, and between deposits and equity on the liability side. The endogenously determined asset portfolio and capital structure interact to support credit extension, as well as to provide liquidity and risk-sharing services to the real economy. Our modifications create wedges in the asset and liability mix between the private equilibrium and a social planner’s equilibrium. Correcting these distortions requires the joint implementation of a capital and a liquidity regulation.

Private and Public Liquidity Provision in Over-the-Counter Markets

We show that trade frictions in OTC markets result in inefficient private liquidity provision. We develop a dynamic model of market-based financial intermediation with a two-way interaction between primary credit markets and secondary OTC markets. Private allocations are generically inefficient because investors and firms fail to internalize how their actions affect liquidity in secondary markets. This inefficiency can lead to liquidity that is suboptimally low or high compared to the second best. Our analysis provides a rationale for the regulation and public provision of liquidity and the effect of quantitative easing or tightening on capital markets and investment.

On the Limitations of Monetary Policy

This paper argues that in a homogeneous monetary Real Business Cycle economy where a complete set of nominal contingent claims exist, the requirement to collateralize loans, alone, does not affect the equilibrium allocation when monetary policy is chosen optimally: the Pareto optimal allocation can be supported. Rather, it is the presence of additional inefficiencies such as market incompleteness or heterogeneity of agents that limits the ability of optimal monetary policy, and more precisely, inflation, to support the first best allocation. In our model policy is non-Ricardian or equivalently outside money exists, and the Central Bank trades only in short-term nominally risk-free bonds: as a consequence monetary policy that sets rates of interest and accommodates money demand effectively determines the allocation of prices at equilibrium. A Friedman rule (r=0), which would be optimal in the absence of collateral constraints, here it is not: at the resulting prices collateral constraints bind. A path of prices that avoids binding collateral constraints necessarily involves a non-zero interest rate. The path of prices that supports the Pareto optimal allocation occurs when the collateral constraint binds: a positive inflation tax on money balances is efficient. For interest rates that permit the collateral constraint to bind, a policy of stable inflation (alternatively, money growth) implies that the collateral constraint binds after a sequence of positive (respectively negative) productivity shocks followed by a negative (respectively positive) productivity shock.