Interdaily Volatility in a Continuous Order-Driven Market

Since Amihud and Mendelson (1987) documented a higher open-to-open return volatility compared to close-to-close return volatility in the US market, there have been various explanations offered, such as call auction opening, a long halt of trade, and specialist systems. No consensus has been reached so far. As an order-driven dealership market, the Hong Kong stock market provides another dimension for examination. If halt of trade is the major cause of the open-to-open volatility in the Hong Kong market, this volatility should also be higher. This is not observed. Positive autocorrelation of the open-to-open return series also suggests that there is no temporary price deviation at market opening. We view these as consistent with the specialist argument put forth by Stoll and Whaley (1990).     

Insider Trading in the Hong Kong Stock Market

Many previous studies on insider trading are based ondata in the U.S. capital market and conclude thatinsiders can earn abnormal profits. This paperexamines abnormal price performance associated withinsider trading in the Hong Kong stock market. We findthat abnormal profits associated with insider tradingare all concentrated on small firms. Trading volumedoes matter in determining the magnitude of thoseabnormal profits. Our results show that insiders ofmedium-sized and large firms do not earn abnormalprofits. Finally, it is found that outsiders who mimicthe information of insider trades associated withmedium-sized and large firms cannot earn abnormalprofits.     

Stock Market Volatility and Economic Factors

This paper examines the ability of rational economic factors to explain stock market volatility. A simple model of the economy under uncertainty identifies four determinants of stock market volatility: uncertainty about the price level, the riskless rate of interest, the risk premium on equity and the ratio of expected profits to expected revenues. In initial tests these variables have significant explanatory power and account for over 50 per cent of the variation in market volatility from 1929 to 1989. When the regression coefficients are allowed to vary over time using cluster regression, the four factors explain over 90 per cent of the variation in market volatility. The results are useful in explaining the past behavior of stock market volatility and in forecasting future volatility.     

A Note on the Intraday Patterns of Initial Public Offerings: Evidence from Hong Kong

This paper examines the intraday patterns of IPOs in Hong Kong during the period 1995–1998. The results reveal that the well‐known under‐pricing phenomenon of IPOs occurs only at the opening trading of new issues and vanishes afterwards. The return volatility of IPOs is found to be high during the first trading session, and declines rapidly during the rest of the first trading day until the end of the trading day. The intraday return volatility of IPOs is found to follow a double U‐shape pattern, which is similar to that of the general market. A great deal of trading activity was recorded during the first five minutes of the trading day. Consistent results are obtained for IPOs registered during the pre‐crisis and post‐crisis periods. This paper has practical implications for investors. Investors can benefit from the under‐pricing only if they subscribe for new shares in the primary market. There is, however, no profit‐making opportunity for day traders who buy shares on the first trading day. This shows that the Hong Kong market is efficient in adjusting for the IPO under‐pricing. In addition, it is likely that, because of Hong Kong's share allotment method, only big investors who apply for large numbers of shares can benefit from this under‐pricing phenomenon.     

Return spread and liquidity: Evidence from Hong Kong ADRs

Fifteen Chinese H-shares listed on the Stock Exchange of Hong Kong are cross listed as ADRs on the NYSE. We empirically determine the role of security specific liquidity associated with those ADRs and their underlying H-shares on return spreads, differences between the returns on ADRs and their corresponding H-shares after controlling for ADRs and H-shares excess market returns and their respective price inverses denoting conditional betas. We use three proxies for liquidity, trading volume, turnover, and illiquidity (Amihud, 2002) and find that only trading volume and turnover are consistent determinants of return spread for the majority of Chinese ADRs with primary listing in Hong Kong Stock Exchange (SEHK). We use a switching regression model and find that the model parameter estimates are not stationary and change, often drastically between pre and post 2000 and 2003. Further tests using Bai Perron indicate return spreads data as non-stationary with multiple regime changes during the sample period. Further the causes of non-stationarity seem to be largely security specific and not driven by broad market swings in either market.     

Overreaction in the Hong Kong stock market

Overreaction reported in the equity markets of the United States, Spain, and Brazil is also observed in the Hong Kong stock market. The “loser” portfolios of the 33 stocks in the Hang Seng Index (HSI), on average, outperform the “winner” portfolios by 9.9% 1 year after the formation periods. Besides its emphasis on the importance of the Hong Kong market in international investment, this paper is unique in some special features related to the overreaction study. Hong Kong has markets for index futures and stock futures. Only three stocks are used in the portfolios. All the stocks in the HSI have large market capitalization and liquidity and can be shorted with no up-tick rule. Unlike other studies in international stock markets, the “arbitrage” portfolio of buying the loser portfolio and shorting the winner portfolio can actually be formed with minimum cost and easy execution, which makes the overreaction phenomena in this study very powerful.     

融资融券对我国股市波动性的影响

本文采集股价指数月收益率和融资融券交易额每月日平均变化率的数据,针对融资融券对我国股市波动性的影响,进行实证检验,并对结果做进一步的解释。     

香港股市与内地股市的联动性研究

本文分3个阶段考察了香港回归以来,香港股市和内地股市之间的联动关系及其变化。协整分析表明,香港股市和内地股市之间存在长期的均衡关系,这种均衡关系在内地资本市场实行股权分置改革后更趋于稳定。Granger因果检验表明,香港回归以来香港股市和内地股市之间的引导关系在经历B股开放和股权分置改革后发生了变化。脉冲响应函数分析从动态的角度进一步验证了香港股市和内地股市之间的引导关系及其变化,并深入分析了单个变量的波动或冲击对其自身及另一变量的影响程度。     

Regulation Change and Volatility Spillovers: Evidence from China's Stock Markets

This paper investigates the structural changes of volatility spillovers between Chinese A-share and B-share markets induced by a regulation change on February 19, 2001, that allowed Chinese domestic investors to trade in the B-share market. The empirical results of the study, using high-frequency intraday data collected from a sample of seventy-eight firms issuing both A-shares and B-shares and employing a bivariate generalized autoregressive conditional heteroskedasticity (GARCH) model, show that after the regulation change, the volatility in A-shares increases the volatility in B-shares, thus increasing the risk of the whole market, whereas the latter reduces the former, thus reducing the risk of the whole market. A further investigation of the determinants influencing these structural changes shows that the following factors can encourage structural changes that reduce overall market risk: government ownership, institutional ownership, firm size, B-share proportion, and market-to-book ratio. Conversely, the following factors can encourage structural changes that increase overall market risk: dual roles of chief executive officer and chairman and the joint effect of firm size and B-share proportion.     

Market Reactions to the Hong Kong Trading Suspensions: Mandatory versus Voluntary

This paper investigates the market reactions to regulator-initiated (mandatory) suspension and issuer-initiated (voluntary) suspension on the Stock Exchange of Hong Kong. It is found that there is substantial devaluation of the stocks during either suspension, and both the variance and trading volume are higher in the post-suspension period than in the pre-suspension period. However, the changes in value and variance are sensitive to the reason for the suspension. The evidence shows that mandatory suspensions are more effective than voluntary suspensions in disseminating information, although both suspensions may not effectively ease unusual volatility immediately.     

Short-Term External Debt and Foreign Exchange Rate Volatility in Emerging Economies: Evidence from the Korea Market

Abstract:

We empirically analyze the main determinants of foreign exchange rate (FX) volatility in emerging market economies using the data of Korea corporations and financial institutions. We find that short-term external debt is more important than trading volume of foreign investors in explaining FX volatility. Our results suggest that short-term debt-controlling measures, such as a tax levy on short-term borrowing, can be more effective in moderating FX volatility than can the measures affecting the trading volume, such as a Tobin tax.     

The Political Economy of Volatility Dynamics in the Hong Kong Stock Market

Despite its obvious importance, little empirical research has examined the impact of political risk on stock market volatility. This paper uses data on the Hong Kong stock market over a long sample period to investigate whether political risk has induced regime shifts in stock market volatility. Regime shifts are modelled via a Markov switching EGARCH model that allows for regime-dependent volatility asymmetry. We find strong evidence of regime shifts in conditional volatility as well as significant volatility asymmetry in high volatility periods. Major political uncertainties were reflected in a switch to the high-volatility regime. However, contrary to popular perceptions, we find no evidence that the Hong Kong stock market has become persistently more volatile since the start of Sino-British political negotiations in 1982.     

The Impact of Information Release on Stock Price Volatility and Trading Volume: The Rights Offering Case

This paper examines whether information released via rights offering announcements induces changes in price volatility and trading volume of underlying stock. The results of this paper provide support for the release of new information via offering announcements and evidence of its effects on price volatility and volume of underlying stock. Specifically, utilization of the announced information by investors is evidenced by greater trading volume following the announcement date than during the pre-announcement period. We interpret this result to mean that informedness dominates consensus. However, stock price volatility decreased from the pre-announcement period to the post-expiration period of rights offerings.     

中国股市波动率的双重不对称性及其解释——基于MS-TGARCH模型的MCMC估计和分析

本文应用MCMC方法估计了上证综指的MS-TGARCH模型,并得出中国股市的波动率存在双重不对称性。其一,每个波动状态中,中国股市的波动率都存在不对称性,其中高波动状态的波动率对好消息的反应显著大于坏消息,而低波动状态则刚好相反;其二,不同状态之间,中国股市波动率的不对称性刚好相反,并且高波动状态伴随着显著大于0的平均收益率。最后,本文从投资者心理、行为以及中国经济大环境等角度进行了解释。     

The Effect of Market Transparency: Volatility and Liquidity in the Korean Stock Market

Faced with unprecedented competition, stock markets should have fairness and transparency. The effects of market transparency for the stock market volatility and liquidity will be investigated using the case of the Korean stock market. The evidence from this study indicates that increasing the market transparency makes the price discovery process more efficient than before from the viewpoint of stock market volatility, and increases the stock market liquidity compared with before.     

Monthly Pattern and Portfolio Effect on Higher Moments of Stock Returns: Empirical Evidence from Hong Kong

Using a direct test, this paper studies the month-of-the-year effect on the higher moments of six industrial stock indices of the Hong Kong market. We also examine the portfolio effect on skewness and kurtosis across month of the year to see if such an anomaly exists. The empirical results support a weak month-of-the-year effect in higher moments of stock returns. Using a complete sample of all possible combinations for each portfolio size, we show that portfolio effect varies across month of the year for both skewness and kurtosis. In particular, our results show that diversification does not necessarily provide benefits to rational investors when the stock return distribution is non-normal, even though portfolio formation can reduce standard deviation. In June, August and October, diversification across industrial sectors results in a more negatively skewed and leptokurtic return distribution, which is not preferred by investors with risk-aversion. Two (one) possible explanations for the portfolio effect on skewness (kurtosis) are also provided. Our empirical results add new evidence to the existence of anomalies in the Hong Kong stock market. This revised version was published online in August 2006 with corrections to the Cover Date.     

Stock Market Volatility in an Emerging Market: Further Evidence from the Athens Stock Exchange

We investigate the time series properties of the daily and weekly returns from the Athens Stock Exchange (ASE) index for the years 1987 to 1997. We investigate whether important time-series characteristics have changed significantly over time. The Greek market has recently undergone major changes including complete capital flow liberalization, the implementation of computerized trading, as well as significant increases in market volume and capitalization; we thus contrast the 1987–90 and 1991–97 periods. Our findings suggest the dynamics of the ASE composite index returns have changed as the market has developed.     

The Impact of Firm-Specific Public News on Intraday Market Dynamics: Evidence from the Turkish Stock Market

This study attempts to discover the intraday firm-specific news announcements and return volatility relation in the Turkish stock market. The GARCH framework is utilized to investigate the impact of firm-specific public news announcements on volatility persistence with and without trading volume. For the majority of the stocks in the sample, the volatility persistence diminishes with the inclusion of firm-specific news, implying that news is impounded rapidly into prices. This effect is more pronounced for larger stocks. When there is no news, the trading volume does not appear to reduce the volatility persistence for the majority of stocks, possibly due to the presence of private information possessed by informed traders.     

央行汇率沟通与股票市场波动

本文基于2005年7月至2017年2月的日度数据,检验中国央行汇率沟通对于股票市场波动率的影响,研究结果发现:(1)央行汇率沟通会对本国股票市场产生明显的溢出效应,并显著增加股票市场的波动率,B股市场波动率反应程度显著强于A股市场。(2)书面沟通的效果强于口头沟通,口头沟通中行长沟通效果强于非行长沟通;汇率贬值的沟通效果显著强于汇率升值沟通。(3)汇率沟通对于股票市场波动率的影响存在着明显的非线性。