Modeling contagion in the Eurozone crisis via dynamical systems

We recently (Castellacci and Choi, 2013) formulated a theoretical framework for the modeling of financial instability contagion using the theories of dynamical systems. Here, our main goal is to model the Eurozone financial crisis within that framework. The underlying system comprises many economic agents that belong to several subsystems. In each instantiation of this framework, the hierarchy and nesting of the subsystems is dictated by the nature of the problem at hand. We describe in great detail how a suitable model can be set up for the Eurozone crisis. The dynamical system is defined by the evolution of the wealths of the individual agents and can be estimated by solving a nonlinear programming problem that incorporates features of prospect theory. Contagion is formulated in terms of how the market instability indicators for the different subsystems and the global system behave. We present several scenarios tailored to recent financial developments in the Eurozone and discussed within our model. These all point to the key role played by the elasticity coefficients of the wealth dynamical system. Accordingly, we put forward general recommendations on how regulators or other super-systemic agents may act to prevent and forestall the spreading of financial distress.     

Tail risk contagion between international financial markets during COVID-19 pandemic

In this paper, we combine the time-varying financial network model and FARM-selection approach to analyze the tail risk contagion between international financial market during the COVID-19 epidemic. Since the tail risk acts as a global transmission channel, we use the sample of 19 international financial markets to explore the contagion of tail risk during the epidemic. We find that the COVID-19 epidemic increases the number of contagion channels in the international financial system. The clustering level of the financial system has a significant growth during the COVID-19 pandemic, and the number of risk drivers is also larger than risk takers. The key financial market of each international financial network is related to the epidemic country. We also consider the tail risk contagion in local financial markets and find that the COVID-19 pandemic has an important influence on the tail risk contagions in local network systems     

Interconnected multilayer networks: Quantifying connectedness among global stock and foreign exchange markets

This paper proposes a novel interconnected multilayer network framework based on variance decomposition and block aggregation technique, which can be further served as a tool of linking and measuring cross-market and within-market contagion. We apply it to quantifying connectedness among global stock and foreign exchange (forex) markets, and demonstrate that measuring volatility spillovers of both stock and forex markets simultaneously could support a more comprehensive view for financial risk contagion. We find that (i) stock markets transmit the larger spillovers to forex markets, (ii) the French stock market is the largest risk transmitter in multilayer networks, while some Asian stock markets and most forex markets are net risk receivers, and (iii) interconnected multilayer networks could signal the financial instability during the global financial crisis and the COVID-19 crisis. Our work provides a new perspective and method for studying the cross-market risk contagion.     

Are stock market crises contagious? The role of crisis definitions

Financial contagion studies generally examine whether co-movement between markets increases during a crisis. We use a flexible co-movement measure to examine how conclusions of such analyses depend on the sample chosen as the ‘crisis’. To this end, we analyse stock market co-movement during the 1997 Asian crisis and the 2007 global financial crisis for all possible source countries and for all possible time periods or extreme return quantiles. This way we account for the main crisis dating approaches adopted in the literature. Our results suggest there is no clear relationship between excess co-movement and commonly used crisis samples.     

A network model of systemic risk: stress testing the banking system1

Although there are many definitions of systemic risk, most agree that it manifests itself by an initial shock that results in the failure of one or more banks and then spreads out to the entire system by a contagion mechanism which can result in the failure of more banks in the system. Assuming that bank failures in the initial shock are randomly dependent on the failure probabilities of the individual banks and that the ensuing contagion process is deterministic, depending on interbank exposures, in this paper we propose a network model to analyse systemic risk in the banking system that, in contrast to other proposed models, seeks to obtain the probability distribution of losses for the financial system resulting from the shock/contagion process. Thus, calculating the probabilities of joint failures by simulation and assuming that the matrix of bilateral interbank exposures is known, we represent systemic risk in the financial system by means of a graph and use discrete modelling techniques to characterize the dynamics of contagion and corresponding losses within the network. The probability distribution of losses, risk profile for the Mexican banking system, is obtained through an efficient, complete enumeration procedure of all possible bank default events in the system. This, in turn, allows the use of the wide variety of well-established risk measures to describe the fragility of the financial system. Additionally, the model allows us to perform stress tests along both the bank default probabilities and the interbank exposures and is used to assess the risk of the Mexican banking system. Copyright © 2009 John Wiley & Sons, Ltd.     

宏观审慎政策协调能否抑制国际性银行危机传染？——基于跨境金融关联视角的实证研究

本文基于跨境金融关联视角对宏观审慎政策能否抑制国际性银行危机传染这一重要的理论与实践问题进行了实证研究。选取亚洲金融危机和全球金融危机时期遭受冲击的10个代表性国家作为样本,构建Logit模型和多元回归模型探讨本国及具有金融关联的国家协调实施宏观审慎政策对本国系统性银行危机传染的影响。研究表明,具有金融关联的国家出现金融危机会显著增加本国系统性银行危机的发生概率,具有金融关联的国家实施宏观审慎政策对本国信贷的影响比对房价的影响更明显,本国及具有金融关联的国家协调实施宏观审慎政策会显著降低本国系统性银行危机的发生概率。在调整银行危机指标及考虑贸易关联和流动性风险的影响后,研究结果依然保持稳健。本文的研究结论揭示了加强宏观审慎政策协调有助于维护全球金融稳定,对于中国政策当局强化宏观审慎管理具有极其重要的政策含义。     

全球股票市场间风险传染的测度、监管及预警

近年来,伴随金融一体化程度的加深,全球各股票市场间风险传染的动态复杂性加剧,其准确测度、高效监管及实时预警已成为优先事项。本研究选取全球21个代表性股票市场作为分析样本,首先基于广义向量自回归模型的滚动估计准确测度其间风险动态传染的高维网络序列,进一步借由矩阵值因子模型来稳健收缩上述序列,以探究其潜在动态核心结构,从而实现高效监管。最后,通过向量自回归模型的预测功能实现对全球股票市场间风险传染的实时预警。研究表明,全球股票市场间风险传染具有时变性,其监管与预警可通过少数与地理区域高度相关的风险区域间的动态传染关系及内部的市场构成来刻画。与此同时,我们发现中国内地等新兴市场的重要地位逐渐凸显。本文研究结论可为有效防范与化解金融风险提供有益参考。     

全球股票市场间风险传染的测度、监管及预警

近年来,伴随金融一体化程度的加深,全球各股票市场间风险传染的动态复杂性加剧,其准确测度、高效监管及实时预警已成为优先事项。本研究选取全球21个代表性股票市场作为分析样本,首先基于广义向量自回归模型的滚动估计准确测度其间风险动态传染的高维网络序列,进一步借由矩阵值因子模型来稳健收缩上述序列,以探究其潜在动态核心结构,从而实现高效监管。最后,通过向量自回归模型的预测功能实现对全球股票市场间风险传染的实时预警。研究表明,全球股票市场间风险传染具有时变性,其监管与预警可通过少数与地理区域高度相关的风险区域间的动态传染关系及内部的市场构成来刻画。与此同时,我们发现中国内地等新兴市场的重要地位逐渐凸显。本文研究结论可为有效防范与化解金融风险提供有益参考。     

The 2008 financial crisis: Stock market contagion and its determinants

In this paper, we investigate worldwide contagion and its determinants during the 2008 financial crisis. Utilizing an international sample of returns from 2003 to 2009, we consider both uni- and bi-directional contagion. After controlling for crisis-related volatility, we find strong evidence that cross-market linkages increase among many financial markets. In contrast to previous crises, contagion following the 2008 global financial crisis is not confined to emerging markets. The United States and other mature financial markets in the sample transmit and receive contagion. Country markets are less influenced by regions than they are by other country markets. We also construct variables that represent relative changes in economic variables before and during the crisis. We find that both economic fundamentals such as trade structure, interest rates, inflation rates, industrial production, and regional effects, and investors’ risk aversion contribute to international contagion.     

The effects of news events on market contagion: Evidence from the 2007–2009 financial crisis

In this paper, we use the quantile regression technique along with coexceedance, a contagion measure, to assess the extent to which news events contribute to contagion in the stock markets during the crisis period between 2007 and 2009. Studies have shown that, not only the subprime crisis leads to a global recession, but the effects on the global stock markets have also been significant. We track the news events, both in the UK and the US, using the global recession timeline. We observe that the news events related to ad hoc bailouts of individual banks from the UK have a contagion effect throughout the period for most of the countries under investigation. This, however, is not found to be the case for the news events originating from the US. Our findings regarding the evidence of contagion effects in the UK reinforce the argument that spreads and contagion—an outcome of the risk perception of financial markets—are solely a result of the behaviour of investors or other financial market participants.     

Investor induced contagion during the banking and European sovereign debt crisis of 2007–2012: Wealth effect or portfolio rebalancing?

This study investigates the way a crisis spreads within a country and across borders by testing the investor induced contagion hypothesis through the liquidity channel on stock-bond relationships of the US and five European countries before and during the global banking and European sovereign debt crisis of 2007–2012. We provide evidence consistent with the wealth effect as a source of contagion for the majority of countries. Nevertheless, we uncover evidence of investor induced contagion sourced by the portfolio rebalancing effect for correlations involving Spanish and Italian bonds during the debt crisis. Further, we find that tight (narrow) credit spreads reduce (magnify) the wealth and portfolio rebalancing effects, which are offset by the opposite effects of risk aversion amongst investors, a dynamic that is not restricted to crisis periods.     

Deposit Insurance, Capital Regulations, and Financial Contagion in Multinational Banks

Abstract:  Banking sector globalization has caused an expansion in foreign-owned bank assets. In this paper we analyse the effects of a MNB's liability structure upon its investment in a foreign country. We develop a model in which capital adequacy requirements introduce some deliberate underinvestment which counters deposit insurance-induced overinvestment. Diversification is unattractive with fixed bank capital requirements, because it reduces the expected value of the deposit insurance net. This effect applies in multinational banks (MNBs), where shocks to the home country economy alter the value of the deposit insurance net and hence affect overseas lending incentives. Thus, MNBs act as a channel for financial contagion. We discuss the policy implications of our results.     

Dynamical macroprudential stress testing using network theory

The increasing frequency and scope of financial crises have made global financial stability one of the major concerns of economic policy and decision makers. This has led to the understanding that financial and banking supervision has to be thought of as a systemic task, focusing on the interdependent relations among the institutions. Using network theory, we develop a dynamic model that uses a bipartite network of banks and their assets to analyze the system’s sensitivity to external shocks in individual asset classes and to evaluate the presence of features underlying the system that could lead to contagion. As a case study, we apply the model to stress test the Venezuelan banking system from 1998 to 2013. The introduced model was able to capture monthly changes in the structure of the system and the sensitivity of bank portfolios to different external shock scenarios and to identify systemic vulnerabilities and their time evolution. The model provides new tools for policy makers and supervision agencies to use for macroprudential dynamical stress testing.     

Crossborder financial contagion to Germany: How important are OTC dealers?

We examine crossborder contagion from a number of financial systems to the German financial system using the information content of CDS prices in a GARCH model. After controlling for common factors which may cause comovement in security prices, we find evidence for contagion from the US and European financial systems. Assessing contagion for dealer and non-dealer banks suggests that contagion from dealer banks is the most prominent source of contagion to the German financial system. While German non-dealer banks are affected both by European and US dealers, only US dealer banks have a contagion effect to German dealer banks.     

Fund Management and Systemic Risk – Lessons from the Global Financial Crisis

Fund managers play an important role in increasing efficiency and stability in financial markets. But research also indicates that fund management in certain circumstances may contribute to the buildup of systemic risk and severity of financial crises. The global financial crisis provided a number of new experiences on the contribution of fund managers to systemic risk. In this article, we focus on these lessons from the crisis. We distinguish between three sources of systemic risk in the financial system that may arise from fund management: insufficient credit risk transfer to fund managers; runs on funds that cause sudden reductions in funding to banks and other financial entities; and contagion through business ties between fund managers and their sponsors. Our discussion relates to the current intense debate on the role the so‐called shadow banking system played in the global financial crisis. Several regulatory initiatives have been launched or suggested to reduce the systemic risk arising from non‐bank financial entities, and we briefly discuss the likely impact of these on the sources of systemic risk outlined in the article.     

With Economic Integration Comes Financial Contagion? Evidence from China

China's economy has maintained a rapid growth rate over the past two decades; however, its stock market has exhibited a very different level of performance during financial crises. In this paper, we try to explain this phenomenon and answer two important questions: Is there financial contagion in China? Can economic integration aggravate financial contagion? We construct a composite index of economic integration by reviewing the incremental reform and opening-up process in China's financial markets. We utilize a dynamic conditional correlation model to capture the correlations between stock returns of China and those of other important markets around the world. The empirical results provide positive evidence for the aforementioned two questions.     

Financial contagion effects of major crises in African stock markets

This study examines financial contagion effects in African stock markets during major crises over the period 2005 to 2020. We investigate contagion effects in individual stock markets and from a regional perspective using dynamic conditional correlations during the global financial crisis, European debt crisis, Brexit, and COVID-19. The empirical evidence confirms contagion effects in some individual markets. However, significant evidence of contagion is found only during the global financial crisis from the regional perspective. Our findings suggest that the regional impacts of crises differ due to the nature of those crises. We also find financial contagion increases in the country-level risk, market capitalization and export to GDP and decreases in corruption.     

金融体系顺周期性与金融危机的发展演变关系研究

金融体系中的顺周期效应是导致金融体系内在不稳定性的重要原因,也是造成金融危机的根源之一.本文对金融体系中的顺周期现象进行了系统性的分析,认为不仅在信贷市场上存在顺周期效应,资本市场同样也存在顺周期效应,且两者之间存在紧密的相互促进作用,通过金融加速器、财富效应等传导至实体经济,放大经济波动周期.本文随后在顺周期的框架下探讨了金融危机的形成及发展、演变机制,并以美国次贷危机为实例加以验证.     

宏观审慎：概念、国际实践和启示

此轮国际金融危机的爆发和蔓延,暴露出仅关注单个机构稳健经营的微观审慎监管框架的不足。认真吸取金融危机的教训,强化宏观审慎管理已成为国际社会的共识。要完善宏观审慎分析方法,加强对系统性风险的监测;加强金融监管和协调,实现宏观审慎与微观审慎的互补;建立逆周期调节机制,缓解顺周期性对金融稳定的影响;加快建立存款保险制度,进一步健全金融安全网;积极参与国际金融合作,增强联合应对危机的能力。     

Unveiling investor-induced channels of financial contagion in the 2008 financial crisis using copulas

Understanding how financial crises spread is important for policy-makers and regulators in order to take adequate measures to prevent or contain the spread of these crises. This paper will test whether there was contagion of the subprime financial crisis to the European stock markets of the NYSE Euronext group (Belgium, France, the Netherlands and Portugal) and, if evidence of contagion is found, it will determine the investor-induced channels through which the crisis propagated. We will use copula models for this purpose. After assessing whether there is evidence of financial contagion in the stock markets, we will examine whether the ‘wealth constraints’ transmission mechanism prevails over the ‘portfolio rebalancing’ channel. An additional test looks at the interaction between stock and bond markets during the crisis and allows us to determine if the transmission occurred due to the ‘cross market rebalancing’ channel or the ‘flying to quality’ phenomenon. The tests suggest that (i) financial contagion is present in all analyzed stock markets, (ii) a ‘portfolio rebalancing’ channel is the most important crisis transmission mechanism, (iii) and the ‘flight-to-quality’ phenomenon is also present in all analyzed stock markets.