我国股市与汇市的波动溢出效应实证研究

本文选取上证综指和人民币对美元名义汇率两个变量,运用GARCH-BEKK模型对我国股市与汇市之间的波动溢出效应进行了实证研究。结果表明,汇改后我国股市与汇市存在双向波动溢出效应,且有非对称性的特点,即汇市对股市的波动溢出效应比股市对汇市的波动溢出效应更强。     

中国创业板市场与中小板市场间的波动溢出效应研究——基于方法比较视角

基于创业板市场与中小板市场的特殊关系,本文分别运用单变量条件异方差模型和多元条件异方差模型考察二者之间的信息传导和波动溢出效应,研究结果表明:(1)创业板市场对中小板市场存在波动的集聚性和持久性溢出效应,中小板市场对创业板市场不存在波动的集聚性溢出效应,但存在波动的持久性溢出效应;(2)创业板市场与中小板市场间均值溢出效应不显著,二者互不构成对方的定价中心;(3)单变量GARCH模型下,创业板市场对中小板市场存在单向的波动溢出效应,而多元GARCH模型下,创业板市场与中小板市场间存在双向波动溢出效应,表明多元GARCH模型效果优于单变量GARCH模型;(4)创业板市场与中小板市场间的波动溢出效应程度均不大,但中小板市场对创业板市场的波动溢出效应程度要大于创业板市场对中小板市场的波动溢出效应程度,表明老市场向新兴市场的信息流动量较大.     

人民币汇率与股票价格的关系研究

本文对人民币汇率与股票价格的相关关系进行了研究,考察了我国股市和汇市的关联性。结果显示,人民币汇率和股票价格存在长期均衡关系,并且人民币汇率和股票价格正相关,人民币汇率和股票价格之间存在双向的因果关系,这说明人民币汇率改革恢复了外汇市场和资本市场应有的联动性。     

中国官方汇率与黑市汇率的结构平稳性和联动性研究

本文试图检验人民币兑换美元的官方汇率和黑市汇率在1961年1月至2005年8月间的结构平稳性,并基于向量自回归(VAR)系统分析这两种汇率的Granger因果性和脉冲响应。同时,从对黑市外汇需求角度剖析了影响黑市名义汇率波动的因素,从而揭示了黑色汇市存在的关键原因。最后,就黑色汇市现状对官方汇市制度的影响进行了深刻反思。     

境内和离岸人民币外汇市场价格传导和波动溢出效应

］从不同经济发展阶段的视角，研究CNY、CNH和NDF市场间的价格传导机制，检验其均值溢出效应及风险溢出效应的存在性，发现并解释其异质特征，剖析CNH市场对CNY市场、NDF市场对CNH市场价格引导作用的微观机理，给出了实证证据。研究发现：这三个市场的波动丛集现象显著且逐渐趋弱；随着时间推移，当下波动对未来市场波动的影响趋缓，但风险和损失对市场冲击的持续期变长。研究还表明：境内外人民币即期汇差存在自动收敛的机制，价格将趋向一致，尽管汇差的收敛速度和波动分别随时间推移加快和收窄，但收敛缓慢、波动较大且在一段时间内保持较高水平，预期和套利机制仍不能充分发挥市场信息传导功能。CNY市场缺乏对离岸CNH市场和NDF市场的价格引导作用，人民币汇率价格从离岸向境内市场传递，离岸市场对境内市场的价格发现功能随人民币市场化和国际化发展逐渐完善，但溢出效应存在滞后性且反馈周期较长。     

沪港通背景下行业间波动溢出效应及形成机理

研究目标：研究资本市场开放是否强化跨境资本市场间的联系及如何促进波动溢出和风险传染等问题。研究方法：运用广义溢出指数法对比分析沪港通开通前后中国内地与中国香港股市行业间波动溢出效应的变化及其形成机理。[HTH]研究发现：沪港通开通前,信息、电信等第三产业的信息溢出水平较高,但沪港通开通后,材料、工业等第二产业的信息溢出能力显著增强;沪港通的实施提高了两市行业间的双向波动溢出程度,且主要增强了上证各行业对恒生行业的波动溢出强度;市盈率效应、规模效应和投资者情绪变化等内地市场的非理性特征也会影响中国内地与中国香港股市间的波动溢出。研究创新：在沪港通政策背景下,从行业层面考察两地股市间的波动溢出效应及形成机理,将风格投资和投资者情绪等非理性行为因素纳入两地资本市场波动溢出的解释框架。研究价值：为两地资本市场的风险传染机制提供更为系统的视角,为检验内地资本市场开放政策提供更为全面的评估,为推行“深港通”等制度提供借鉴。     

中、美、日实际均衡汇率模型的构建及实证研究

本文基于BEKK-MGARCH模型建立了中、美、日三国的实际均衡汇率方程和方差方程,对1994年以来中国、美国和日本的实际均衡汇率及其波动溢出效应进行了深入细致的分析。结果表明:三个国家的实际均衡汇率受其经济基本面因素的影响不同,人民币实际均衡汇率还受到了美元和日元实际汇率的影响;中美、中日、美日之间的联动关系存在显著的ARCH和GARCH效应。     

交易量适合作为股价波动信息的代理变量吗?——来自中国沪深股市的证据

本文利用中国沪深股市日交易数据,采用多元GARCH模型从信息传递的角度进行实证研究,结果表明:股价对交易量具有显著的波动溢出效应,但交易量对股价的波动溢出效应不明显。这种波动的单向溢出说明在应对信息的冲击上股价比交易量能更快地做出反应,其后才通过波动溢出在交易量上得到反映,股价波动对成交量波动具有先导作用。因此,从波动冲击传导和信息传递的角度看,单纯地将交易量视为股价变动信息的代理变量还缺乏稳健的统计证据。     

金砖国家股市相依结构研究——基于藤Copula-GARCH方法

在藤Copula理论研究框架下,本文构建Pair Copula-GARCH类模型,并分别采用C藤和D藤结构分解下的t-Copula、Clayton Copula和SJC Copula函数来研究金砖国家股票市场之间的动态相依性结构以及波动溢出效应。研究发现,D藤分解模式下的t-Copula模型更适合描述金砖国家股票市场的数据。研究还表明,巴西和印度、俄罗斯和南非股市间存在很强的波动溢出效应,而巴西和南非股市间则最弱。另外,在D藤结构下,巴西和南非市场出现极值的可能性最小,而巴西和印度市场出现极值的可能性则最大。     

国内外期货市场之间波动性溢出效应——基于沪铜和美铜的实证检验

本文用BEKK多元GARCH模型对国内外期货市场之间的波动性特征以及波动溢出效应进行实证检验。结果证明:国内期货市场对国外期货市场存在显著的波动溢出效应,与此同时,国外期货市场也对国内期货市场有着显著的波动溢出效应。     

我国金融市场间溢出效应研究——基于四元VAR-GARCH(1,1)-BEKK模型的分析

汇率改革以来,政府实施了一系列金融市场改革,促使金融市场一体化程度显著提高,增强了金融市场间联系。本文采用四元VAR(6)-GARCH(1,1)-BEKK模型分析了我国主要金融市场(股票市场、债券市场、外汇市场以及货币市场)的溢出关系。研究发现,上述市场有很强的波动集聚性和持续性,大多数金融市场间存在显著的双向均值溢出,所有市场间均存在显著的双向波动溢出,还发现市场间溢出可能主要来自于市场传染效应。据此,本文认为政府应该采取合理有效的监管框架,监控金融市场参与者的资本金状况,防止金融市场大幅波动,降低风险累积程度,并在执行货币政策时,兼顾金融市场价格变化对货币政策执行效力的影响。     

Following the leaders? A study of co-movement and volatility spillover in BRICS currencies

The paper investigates return co-movement and volatility spillover among the currencies of Brazil, Russia, India, China, and South Africa (the BRICS member countries) and four major developed countries from April 2006 to October 2019. Using Bloomberg daily data on exchange rates, the study employs a flexible multivariate generalized autoregressive conditional heteroskedasticity (MGARCH)–dynamic conditional correlation (DCC) model and a vector autoregressive (VAR)–based spillover index, as the empirical strategy. Along with evidence of exchange rate volatility in BRICS currencies, among which the Russian ruble and the Chinese yuan are explosive, the econometric estimation results show the presence of significant return co-movement and volatility spillover among the foreign exchange markets across different countries. The currency markets in developed countries, as leaders, are found to transmit volatility mostly to BRICS currency markets, which are net receivers. The degree of spillover, however, varies across countries, with Brazil and Russia passing on volatility to the developed countries whereas India, China, and South Africa receive volatility from their developed counterparts.     

Unification of Dual Foreign Exchange Markets

In this paper I investigate the impact of overnight floating of the official rate and easing foreign exchange restrictions on post-unification domestic inflation rate. After analysing the behaviour of an economy under dual foreign exchange markets, an official market with a crawling foreign exchange rate and a free illegal parallel market. The paper also shows that maintaining a unified free exchange rate depends on the degree of foreign exchange restrictions under dual foreign exchange system and on the level of the official reserve that prompts foreign exchange liberalisation policy. This revised version was published online in July 2006 with corrections to the Cover Date.     

Measuring extreme risk spillovers across international stock markets: A quantile variance decomposition analysis

This paper proposes a quantile variance decomposition framework for measuring extreme risk spillover effects across international stock markets. The framework extends the spillover index approach suggested by Diebold and Yilmaz (2009) using a quantile regression analysis instead of the ordinary least squares estimation. Thus, the framework provides a new tool for further study into the extreme risk spillover effects. The model is applied to G7 and BRICS stock markets, from which new insights emerged as to the extreme risk spillovers across G7 and BRICS stock markets, and revealed how extreme risk spillover across developed and emerging stock markets. These findings have important implications for market regulators.     

Risk spillover from crude oil prices to GCC stock market returns: New evidence during the COVID-19 outbreak

In this study, we examine oil price extreme tail risk spillover to individual Gulf Cooperation Council (GCC) stock markets and quantify this spillover’s shift before and during the COVID-19 pandemic. A dynamic conditional correlation generalized autoregressive heteroscedastic (DCC- GARCH) model is employed to estimate three important measures of tail dependence risk: conditional value at risk (CoVaR), delta CoVaR (ΔCoVaR), and marginal expected shortfall (MES). Using daily data from January 2017 until May 2020, results point to significant systemic oil risk spillover in all GCC stock markets. In particular, the effect of oil price systemic risk on GCC stock market returns was significantly larger during COVID-19 than before the pandemic. Upon splitting COVID-19 into two phases based on severity, we identify Saudi Arabia as the only GCC market to have experienced significantly higher exposure to oil risk in Phase 1. Although all GCC stock markets received greater oil systemic risk spillover in Phase 2 of COVID-19, Saudi Arabia and the United Arab Emirates appeared more vulnerable to oil extreme risk than other countries. Our empirical findings reveal that investors should carefully consider the extreme oil risk effects on GCC stock markets when designing optimal portfolio strategies, minimizing portfolio risk, and adopting dynamic diversification process. Policymakers and regulators should also enact awareness, oversight, and action plans to minimize adverse oil risk effects.     

Spatial spillover effects and risk contagion around G20 stock markets based on volatility network

Employing the spatial econometric model as well as the complex network theory, this study investigates the spatial spillovers of volatility among G20 stock markets and explores the influential factors of financial risk. To achieve this objective, we use GARCH-BEKK model to construct the volatility network of G20 stock markets, and calculate the Bonacich centrality to capture the most active and influential nodes. Finally, we innovatively use the volatility network matrix as spatial weight matrix and establish spatial Durbin model to measure the direct and spatial spillover effects. We highlight several key observations: there are significant spatial spillover effects in global stock markets; volatility spillover network exists aggregation effects, hierarchical structure and dynamic evolution features; the risk contagion capability of traditional financial power countries falls, while that of “financial small countries” rises; stock market volatility, government debt and inflation are positively correlated with systemic risk, while current account and macroeconomic performance are negatively correlated; the indirect spillover effects of all explanatory variables on systemic risk are greater than the direct spillover effects.     

国际金融市场波动溢出效应与动态相关性

在DCC GARCH、DCC EGARCH、DCC TGARCH方法下,采用中、美、日、德、英等国家1993年1月至2013年12月的金融数据,实证得出如下结论：样本国市场利率和股指波动率呈现尖峰、肥尾、有偏的特征,更为符合t分布。样本国市场利率波动表现出显著的溢出效应、杠杆效应和联动效应。样本国股指波动率对中国股指波动率的溢出效应趋于增强,特别在美国金融危机后。样本国利率波动对中国股指波动率具有一定的溢出效应和杠杆效应,但影响程度非常低。治理世界性金融风险,各国当局应加强政策协调性,合理进行风险分担。     

Economic policy uncertainty and stock market sector time-varying spillover effect: Evidence from China

This paper investigates the volatility spillover effect among the Chinese economic policy uncertainty index, stock markets, gold and oil by employing the time-varying parameter vector autoregressive (TVP-VAR) model. Three main results are obtained. Firstly, the optional consumption, industry, public utility and financial sectors are systemically important during the sample period. Secondly, among the four policy uncertainties, the uncertainty of fiscal policy and trade policy contributes more to the spillover effect, while the uncertainty of monetary policy and exchange rate policy contributes less to the spillover effect. Thirdly, during COVID-19, oil spillovers from other sources dropped rapidly to a very low point, it also had a significant impact on the net volatility spillover of the stock market. This paper can provide policy implication for decision-makers and reasonable risk aversion methods for investors.     

Risk spillovers and hedge strategies between global crude oil markets and stock markets: Do regime switching processes combining long memory and asymmetry matter?

This paper investigates risk spillovers and hedge strategies between global crude oil markets and stock markets. In the paper, we propose a multivariate long memory and asymmetry GARCH framework that integrates state-dependent regime switching in the mean process with multivariate long memory and asymmetry GARCH in the variance process. Our results first show that there are linear risk spillovers running from the US stock markets to the WTI oil market in the short term. However, the linear risk spillover effect running from the oil market to the US stock market can only exist in the long term. In addition, there is a bidirectional linear risk spillover effect between the European stock markets and the Brent oil market in the short and long terms. Furthermore, there is no linear risk spillover effect between the Dubai oil market and the Chinese stock market. Second, the nonlinear risk spillovers running from the WTI oil market to the US stock market can be found in the tranquil regime. Moreover, there is also a nonlinear risk spillover effect running from the European stock markets to the Brent oil market in the tranquil regime. In addition, the nonlinear risk spillover effect running from the Brent oil markets to the European stock market can be found in the crisis regime. Furthermore, there is bidirectional nonlinear Granger causality between the Dubai crude oil market and the Chinese stock market in the tranquil regime. Finally, dynamic hedge effectiveness shows that the regime switching process combined with long memory and asymmetry behavior seems to be a plausible and feasible way to conduct hedge strategies between the global crude oil markets and stock markets.     

Expectations Formation and Risk in Three Financial Markets: Surveying What the Surveys Say

This paper attempts to provide a logical overview of the literature which exploits survey data to examine issues of expectations formation and risk aversion in financial markets. Our survey suggests that: short term expectations are excessively volatile and exhibit bandwagon effects, while longer term expectations appear to be regressive and therefore stabilising; in bond and foreign exchange markets the standard result of forward rate biasedness is due in part to time-varying premia; recent research using disaggregate foreign exchange survey data demonstrates the importance of heterogeneous expectations.