Testing for financial contagion based on a nonparametric measure of the cross‐market correlation

When contagion is defined as a significant increase in market comovement after a shock to one country, we propose a test for financial contagion based on a nonparametric measure of the cross-market correlation. Monte Carlo simulation studies show that our test has reasonable size and good power to detect financial contagion, and that Forbes and Rigobon's test (2002) is relatively conservative, indicating that their test tends not to find evidence of contagion when it does exist. Applying our test to investigate contagion from the 1997 East Asian crisis and the 2007 Subprime crisis, we find that there existed international financial contagion from the two financial crises.     

The anatomy of sovereign risk contagion

The channels for the cross-border propagation of sovereign risk in the international sovereign debt market are analysed. Identifying sovereign credit events as extraordinary jumps in CDS spreads, we distinguish between the immediate effects of such events and their longer term spillover effects. To analyse “fast and furious” contagion, we use daily CDS data to conduct event studies around a total of 89 identified credit events in a global country sample. To analyse “slow-burn” spillover effects, we apply a multifactor risk model, distinguishing between global and regional risk factors. We find that “fast and furious” contagion has been primarily a regional phenomenon, whilst “slow-burn” spillover effects can often be global in scope, especially those of the recent European debt crisis. The global risk factors are found to be driven by investor risk appetites and debt levels, whilst the regional factors depend on economic fundamentals of countries within a region.     

Sovereign Risk Contagion in East Asia: A Mixture of Time-Varying Copulas Approach

This study analyzes sovereign risk contagion between four East Asian economies (China, Hong Kong, Japan, and Korea) and its structural changes through the Global Financial Crisis (GFC) and the European Debt Crisis (EDC) by applying the mixture of time-varying copulas to those economies’ credit default swap (CDS) spreads.

This article first finds a strong contagion from the US and PIIGS economies to the East Asian sovereign CDS markets and intraregional contagion within the East Asian markets. Second, the impact of contagion is different according to whether it is measured by the linear (Gaussian) or the upper tail dependence. Third, Japan plays an important role in increasing the linear dependence whereas China and Korea are crucial in terms of the upper tail dependence. Lastly, the GFC has structurally increased the linear dependence but not the upper tail dependence between the East Asian sovereign CDS markets.     

‘Slow-burn’ spillover and ‘fast and furious’ contagion: a study of international stock markets

‘Fast and furious’ contagion across capital markets is an important phenomenon in an increasingly integrated financial world. Different from ‘slow-burn’ spillover or interdependence among these markets, ‘fast and furious’ contagion can occur instantly. To investigate this kind of contagion from the US, Japan and Hong Kong to other Asian economies, we design a research strategy to capture fundamental interdependence, or ‘slow-burn’ spillover, among these stock markets as well as short-term departures from this interdependence. Based on these departures, we propose a new contagion measure which reveals how one market responds over time to a shock in another market. We also propose international portfolio analysis for contagion via variance decomposition from the portfolio manager’s perspective. Using this research strategy, we find that the US stock market was cointegrated with the Asian stock markets during four specific periods from 3 July 1997 to 30 April 2014. Beyond this fundamental interdependence, the shocks from both Japan and Hong Kong have significant ‘fast and furious’ contagion effects on other Asian stock markets during the US subprime crisis, but the shocks from the US have no such effects.     

Measuring financial contagion: A Copula approach

This paper models dependence with switching-parameter copulas to study financial contagion. Using daily returns from five East Asian stock indices during the Asian crisis, and from four Latin American stock indices during the Mexican crisis, it finds evidence of changing dependence during periods of turmoil. Increased tail dependence and asymmetry characterize the Asian countries, while symmetry and tail independence describe the Latin American case. Structural breaks in tail dependence are a dimension of the contagion phenomenon. Therefore, the rejection of the correlation breakdown hypothesis should not be considered, without further investigation, as evidence of a stable dependence structure.     

Testing financial contagion on heteroskedastic asset returns in time-varying conditional correlation

We suggest that there is a significant relationship between cross-market comovement and time varying volatility. The time-varying component of cross-market dependence is attributed to the intertemporal risk-return adjustment by rational, risk-averse investors who systematically revise their expectation in response to changing volatility. To reflect the time-varying component of cross-market dependence, we propose a time-varying correlation test for contagion. Our results show that out of the countries reporting contagion evidence under the constant correlation test, none of the countries exhibits contagion evidence from the 1997 Asian crisis. We conclude that a high level of cross-market correlation during a crisis reported as contagion evidence under the standard constant correlation test is mostly due to the high level of cross-market co-movement resulting from the intertemporal risk-return adjustment.     

A P.D.E. approach to Asian options: analytical and numerical evidence

We first derive a one-state-variable partial differential equation, easy to implement, which characterizes the price of a European type Asian option. This result is explained and related to previous literature. We then derive new results on the hedging of an Asian option and propose analytical and numerical analysis on the comparison between Asian and European options. Our methodology which applies to “fixed-strike” Asian options as well as to “floating-strike” Asian options completes and clarifies various results in the literature. In this paper we focus on “backward-starting” Asian options. Our approach is quite general however, and we explain how to adapt our main results to the case of “forward-starting” Asian options.     

The Systemic Risk of Cross-Border Banking: Evidence from the Sudden Stop and Interbank Stress Contagion in East Asia

This article investigates the systemic risk of cross-border banking in East Asia. Using the recursive bivariate probit model, we jointly test the probability of the sudden stop in international lending and its simultaneous effect on the host countries’ interbank markets. The empirical results suggest that the risk of a sudden stop is associated with global liquidity shock; host country productivity shock; and the common lender contagion effect. This facilitates the transmission of interbank stress from advanced economies to emerging markets. However, the tension is mitigated by the “flight-home effect” caused by domestic investors’ repatriation. The sudden stop is more likely to occur in countries with lower financial openness but higher financial risk. Lending flows to the banking sectors are more sensitive to shocks than the flows to the non-bank private sectors.     

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。     

East Asia and Europe during the 1997 Asian collapse: a clinical study of a financial crisis

Asian stock markets are compared with European markets before and during the 1997 Asian crisis. The clinical issue is whether regional inter-dependence became larger around the crisis, fomenting investor fears of contagion and reducing asset values because of lower diversification potential. Statistical measures are developed to aid in this inquiry. We find that European and East Asian countries were not susceptible to volatility contagion in the pre-crisis era but that susceptibility increased significantly with the onset of the crisis. Covariances, correlations, and volatilities increased from the pre-crisis to the crisis period in both regions, but the percentage increases were much larger in Asia. Diversification potential was better in Asia than in Europe before the crisis; this was reversed during the crisis. The observed decline in diversification potency in Asia is reason enough for large declines in asset values though one cannot prove, of course, that it was the cause rather than the effect of the crisis. Exchange rate volatility played a major role.     

Credit Contagion Channels: Market Microstructure Evidence from Lehman Brothers’ Bankruptcy

Immediately after Lehman Brothers’ bankruptcy, many firms disclosed their financial exposure (or lack thereof) to Lehman. This offers a clean setting to test two credit contagion channels through which a financial firm's bankruptcy can affect other firms—“counterparty risk” and “information transmission” channels. Using market microstructure variables to measure the various dimensions of contagion effects, we provide robust evidence supporting the significance of counterparty risk. Firms with exposure to Lehman suffered more severe negative effects—wider bid‐ask spread, higher price impact, greater information asymmetry, and greater selling pressure—than unexposed firms. We find mixed evidence regarding the information transmission hypothesis.     

Tail risk measurement in crypto-asset markets

The paper examines the relationships among market assets during stressful times, using two recently proposed econometric modeling techniques for tail risk measurement: the extreme downside hedge (EDH) and the extreme downside correlation (EDC). We extend both measures taking into account the sensitivity of asset's return to innovations not only from the overall market index, but also from its components, by means of network modeling. Applying our proposal to the cryptocurrencies market, we find that crypto-assets can be clustered in two groups: speculative assets, such as Bitcoin, which are mainly “givers” of tail contagion; and technical assets, such as Ethereum, which are mainly “receivers” of contagion.     

Correlation in corporate defaults: Contagion or conditional independence?

We revisit a method used by Das et al. (2007) (DDKS) who jointly test and reject a specification of firm default intensities and the doubly stochastic assumption in intensity models of default. The method relies on a time change result for counting processes. With an almost identical set of default histories recorded by Moody’s in the period from 1982 to 2006, but using a different specification of the default intensity, we cannot reject the tests based on time change used in DDKS. We then note that the method proposed by DDKS is mainly a misspecification test in that it has very limited power in detecting violations of the doubly stochastic assumption. For example, it will not detect contagion which spreads through the explanatory variables “covariates” that determine the default intensities of individual firms. Therefore, we perform a different test using a Hawkes process alternative to see if firm-specific variables are affected by occurrences of defaults, but find no evidence of default contagion.     

基于共同冲击和异质风险叠加传导的风险传染研究——来自中国上市银行网络的传染模拟

本文将银行系统遭遇外部共同冲击作为研究起点,建立了一个共同冲击和异质风险交互传导与放大的简化模型,冲击的传导包括“原始冲击”、“增量冲击”和“违约冲击”三个风险传染阶段。基于2018年我国15家上市银行的股票收益率和年报数据、2006年至2018年的银行评级数据,本文构建了贝叶斯分层图模型和银行间拆借矩阵,并利用蒙特卡洛模拟测度不同触发银行所引发的系统性风险损失、单个银行的系统性风险杠杆能力(文中定义为“传染乘数”指标)以及政府监管介入的效果。模拟结果显示:共同冲击损失远大于异质风险损失;规模和网络关联性是决定传染乘数的重要因素,且当规模因素不突出时,网络关联性对传染乘数的决定作用相对更强,极容易出现小规模、高关联性银行具有较高的传染乘数;当银行风险资产损失率在10%至25%之间时,造成系统性风险损失的杠杆能力普遍增强;政府监管介入能较好地降低系统性风险。本研究的相关结论为系统性风险的监管设计提供经验证据和参考。     

投资者理性预期、流动性约束与股价崩盘传染研究

“传染性”是股价崩盘三大基本特征之一,会加剧股价崩盘负面影响,甚至引发系统性金融风险,因此,本文重点关注股价崩盘传染机制研究。首先,本文基于两阶段理性预期均衡模型,提出股价崩盘传染两大假设,即投资者理性预期与流动性约束导致传染;其次,基于2000-2016年全球28个国家或地区资本市场数据,实证检验股价崩盘传染机制和传染渠道。研究显示:(1)投资者理性预期、流动性约束会导致股价崩盘发生传染;(2)股价崩盘事件会在资本市场关联国家或地区传染;(3)提高资本市场信息透明度、加强金融管制有助于降低受关联国家或地区股价崩盘传染。     

The Global Crisis and Equity Market Contagion

We analyze the transmission of the 2007 to 2009 financial crisis to 415 country‐industry equity portfolios. We use a factor model to predict crisis returns, defining unexplained increases in factor loadings and residual correlations as indicative of contagion. While we find evidence of contagion from the United States and the global financial sector, the effects are small. By contrast, there has been substantial contagion from domestic markets to individual domestic portfolios, with its severity inversely related to the quality of countries’ economic fundamentals. This confirms the “wake‐up call” hypothesis, with markets focusing more on country‐specific characteristics during the crisis.     

The lender of last resort

This paper develops a model of the lender of last resort (LOLR) from a Central Bank (CB) viewpoint. The model in a static setting suggests that the CB would only rescue banks which are above a threshold size, consistent with the insight of “too big to fail”. In a dynamic setting, CB’s optimal policy in liquidity support depends on the trade off between contagion and moral hazard effects. Our results show that contagion is the key factor affecting CB’s incentives in providing LOLR and they also provide a rationalization for “constructive ambiguity”.     

On the Economics of Postassessments in Insurance Guaranty Funds: A Stakeholders’ Perspective

This article proposes a model that suggests there are contagion effects among members of an insurance guaranty fund when postassessments are charged to all other insurers upon the failure of a member company. Indeed, these extraordinary payments are shown to increase the default rate of other firms in the industry, ultimately lowering the value of corporate claims as well as government tax claims. The model is also used to examine the efficiency of different recoupment mechanisms (both existing and new) used by regulators and insurers to potentially reduce these contagion effects. Analysis allows us to stipulate the conditions under which a “tax carryforward” provision could be more efficient than the usual recoupment mechanisms known as “premium rate surcharge” and “premium tax credit.”     

A cospectral analysis of exchange rate comovements during Asian financial crisis

Comovements of exchange rates before and during Asian financial crisis are examined using cross-spectral methodology. The paper proposes and implements a simple frequency-domain-based test for contagion that avoids biases of the correlation breakdown tests used in the extant literature. The Asian crisis is found to be manifest in greater comovements along high-frequency components. Calculated changes in the high-frequency portion of the covariance indicate a contagion for 48 out of the possible 66 pairs of countries in the sample.