Prasanna Gai

Contagion in financial networks

This paper develops an analytical model of contagion in financial networks with arbitrary structure. We explore how the probability and potential impact of contagion is influenced by aggregate and idiosyncratic shocks, changes in network structure and asset market liquidity. Our findings suggest that financial systems exhibit a robust-yet-fragile tendency: while the probability of contagion may be low, the effects can be extremely widespread when problems occur. And we suggest why the resilience of the system in withstanding fairly large shocks prior to 2007 should not have been taken as a reliable guide to its future robustness.

Funding liquidity risk in a quantitative model of systemic stability

We demonstrate how the introduction of liability-side feedbacks affects the properties of a quantitative model of systemic risk. The model is known as RAMSI and is still in its development phase. It is based on detailed balance sheets for UK banks and encompasses macro-credit risk, interest and non-interest income risk, network interactions, and feedback effects. Funding liquidity risk is introduced by allowing for rating downgrades and incorporating a simple framework in which concerns over solvency, funding profiles and confidence may trigger the outright closure of funding markets to particular institutions. In presenting results, we focus on aggregate distributions and analysis of a scenario in which large losses at some banks can be exacerbated by liability-side feedbacks, leading to system-wide instability.

Financial innovation, macroeconomic stability and systemic crises

We present a general equilibrium model of intermediation designed to capture some of the key features of the modern financial system. The model incorporates financial constraints and state-contingent contracts, and captures the spillovers associated with asset fire sales during periods of stress. If a sufficiently severe shock occurs during a credit expansion, these spillovers can potentially generate a systemic financial crisis that may be self-fulfilling. Our model suggests that financial innovation and greater macroeconomic stability may have made financial crises in developed countries less likely than in the past, but potentially more severe.

Sovereign liquidity crises: analytics and implications for public policy

This paper offers an analytical framework with which to assess some recent proposals for strengthening the international financial architecture. A model is developed of sovereign liquidity crises that reflect two sources of financial stress?weak fundamentals and self-fulfilling expectations. The nature of the underlying co-ordination game is investigated, as are the properties of the unique equilibrium. In so doing, the paper characterises the welfare costs of belief-driven crises, which are found to be potentially significant. Some recent policy proposals are also evaluated, including prudent debt and liquidity management, capital controls, greater information disclosure, and the efficacy of monetary policy tightening in the midst of crisis.

Crisis costs and debtor discipline: the efficacy of public policy in sovereign debt crises

Recent debate on the reform of the international financial architecture has highlighted the potentially important role of the official sector in crisis management. We examine how such public intervention in sovereign debt crises affects efficiency, ex ante and ex post. Our results shed light on the scale of capital inflows in such a regime, and we establish conditions under which this leads to an improvement in debtor country welfare. The efficacy of measures such as officially sanctioned stays on creditor litigation depend critically on the quality of public sector surveillance and the size of the costs of sovereign debt crises.

Systemic risk in modern financial systems: analytics and policy design

Purpose - In recent years, the financial system has been changing rapidly. At the same time, macroeconomic volatility has fallen in developed countries. The purpose of this paper is to examine how these developments may have affected the nature of systemic crises. The paper also aims to discuss how central banks and other financial regulators might respond to these developments with a clearer, more rigorous, operational framework for their systemic financial stability work. Design/methodology/approach - The paper describes analytical models developed at the Bank of England to assess how recent developments may have affected the probability and potential impact of systemic financial crises. The results from these models help to shape the practical framework for the Banks financial stability work. Findings - The models suggest that financial innovation and integration, coupled with greater macroeconomic stability, have served to make systemic crises in developed countries less likely than in the past, but potentially more severe. Implementing a practical framework for financial stability work in response to this raises many formidable challenges. Practical implications - If individuals are risk-averse, the recent change in the profile of crises could lower welfare and would suggest that policymakers should place a higher premium on actions to monitor and mitigate systemic risk. The analysis also highlights the importance of differentiating the probability of risks from their potential impact. Originality/value - The paper will be of interest to academics interested in systemic risk, central bankers, financial regulators, and financial market participants.

SOVEREIGN RISK IN THE CLASSICAL GOLD STANDARD ERA

This paper reassesses the determinants of sovereign bond yields during the classical gold standard period (1872–1913) using the pooled mean group methodology. We find that, rather than lowering risk premia directly, membership of the gold standard hastened the convergence of sovereign bond spreads to their long-run equilibrium levels. Our results also suggest that investors looked beyond the gold standard to country-specific fundamental factors when pricing and differentiating sovereign risk.

Procyclicality, Collateral Values and Financial Stability

This paper analyses how the risk-sharing capacity of the financial system varies over the business cycle, leading to procyclical fragility. We show how financial imperfections contribute to underinsurance by entrepreneurs, generating an externality that leads to the build-up of systematic risk during upturns. Increased asset price uncertainty emerges as a symptom of the sectoral concentration that builds up during booms. The liquidity of the collateral asset is shown to play a key role in amplifying the financial cycle. The welfare costs of financial stability, in terms of the efficiency costs due to financial frictions and the volatility costs due to amplification, are also illustrated.

Covered bonds, core markets, and financial stability

We examine the financial stability implications of covered bonds. Banks issue covered bonds by encumbering assets on their balance sheet and placing them within a dynamic ring fence. As more assets are encumbered, jittery unsecured creditors may run, leading to a banking crisis. We provide conditions for such a crisis to occur. We examine how different over-the-counter market network structures influence the liquidity of secured funding markets and crisis dynamics. We draw on the framework to consider several policy measures aimed at mitigating systemic risk, including caps on asset encumbrance, global legal entity identifiers, and swaps of good for bad collateral by central banks.

The Rise and Fall of Trust Networks

The working of economies relies on trust, with credit markets being a notable example. The evaporation of trust may precipitate the economy from a good to a bad state, with long-lasting and large scale structural changes, witness the 2007/8 global financial crisis. Drawing on insights from the literature on coordination games and network growth, we develop a simple model to clarify how trust breaks down in financial systems. We show how the arrival of bad news about a financial agent can lead others to lose confidence in it and how this, in turn, can spread across the entire system. Our model exhibits hysteresis behavior, suggesting that it takes considerable effort to regain trust once it has been broken, emphasizing the self-reinforcing nature of trust at the systemic level. Although simple, the model provides a plausible account of the credit freeze that followed the global financial crisis of 2007/8.