The Effectiveness of Price Limits and Stock Characteristics: Evidence from the Shanghai and Shenzhen Stock Exchanges

We examine the effectiveness of price limits on Chinese A shares and investigate the characteristics of those stocks that hit their price limits more frequently. We find that the effect of price limits is asymmetric for the A shares in upward and downward price movements and different for bullish and bearish sample periods. During a bullish period price limits effectively reduce stock volatility for downward price movements, but not for upward price movements; while during a bearish period price limits effectively reduce stock volatility for upward price movements, but not for downward price movements. Second, price limits delay efficient price discovery for upward price movements, but not for downward price movements. However, we do not find evidence to suggest that price limits harmfully interfere with the stock trading processes in the Chinese A share markets. Finally, we find that actively traded stocks hit their price limits more often and tend to hit the lower limit more frequently when overall market conditions are bearish. Stocks with high book-to-market values of equity hit their upper price limits more frequently, while stocks with a high ratio of tradable shares tend to hit their price limits less frequently.JEL Classification: G10, G14, G15     

投资者关注与市场反应——来自中国证券交易所交易公开信息的自然实验

涨停的股票能否被交易公开信息披露取决于收益率排名中的随机因素,与股票的基本面特征无关。本文利用这一机制设计自然实验检验了投资者关注对股价的影响。实证结果显示交易公开信息披露使股票受到投资者更多的关注,增加了小额资金的净流入,减少了大额资金的净流入和股价的短期收益率,抑制了股价短期波动率,同时降低了股价在长期发生反转的可能性。频繁登上交易公开信息的知名营业部买入的股票受到更多关注,相应的市场反应也更加显著。进一步的研究表明监管性信息披露引发的投资者关注通过降低市场信息不对称抑制了股价反转。     

Stock price synchronicity and liquidity

We argue and provide evidence that stock price synchronicity affects stock liquidity. Under the relative synchronicity hypothesis, higher return co-movement (i.e., higher systematic volatility relative to total volatility) improves liquidity. Under the absolute synchronicity hypothesis, stocks with higher systematic volatility or beta are more liquid. Our results support both hypotheses. We find all three illiquidity measures (effective proportional bid-ask spread, price impact measure, and Amihud's illiquidity measure) are negatively related to stock return co-movement and systematic volatility. Our analysis also shows that larger industry-wide component in returns improves liquidity. We find that improvement in liquidity following additions to the S&P 500 Index is related to the stock's increase in return co-movement.     

信息不对称、过度自信与股价变动

信息传导的非同步和投资者情绪变化是股票市场的两个典型特征,前者会引发投资者之间出现信息不对称问题,后者主要体现为投资者过度自信,两者共同作用影响股票价格变动。本文将信息不对称和投资者过度自信情绪置于同一个分析框架,建立两阶段动态序贯定价理论模型研究现实市场上信息传导过程中股价变动的内在机制。结果表明:(1)面临新信息的进入,投资者对股票收益预期的调整与均衡价格之间具有正相关关系;(2)面临有利消息时,过度自信投资者比例越大,股票的均衡价格越高,投资收益将越低;面临不利消息时则相反;(3)随着过度自信投资者比例以及过度自信程度升高,市场风险溢价将下降;(4)投资者群体在信息传导过程中出现分化,对股价变动形成异质信念,未获取信息和获取信息但未出现过度自信的投资者认为股价被高估,获取信息且出现过度自信的投资者认为价格被低估,促使更多的交易,引发市场成交量和股价变动;(5)过度自信投资者比例与过度自信程度提高均会对市场效率产生正向影响,而对市场深度具有负向效应。最后,基于理论结果对非对称性和持续性等典型的市场波动性特征进行解释。     

Stock returns after major price shocks: The impact of information

This paper focuses on stocks that experience major price changes. Using analyst reports as a proxy, I find that price events accompanied by information are followed by drift, while no-information ones result in reversals. One interpretation of these results is that investors underreact to news about fundamentals and overreact to other shocks that move stock prices. Consistent with this hypothesis, information-based price changes are more strongly correlated with future earnings surprises than no-information ones. Furthermore, drift exists only when the direction of the price move and of the change in analyst recommendations have the same sign. Finally, the ratio of no-information to information-based price shocks is strongly correlated with aggregate implied volatility and also forecasts momentum returns.     

Price Limit Performance: Evidence from the Tokyo Stock Exchange

Price limit advocates claim that price limits decrease stock price volatility, counter overreaction, and do not interfere with trading activity. Conversely, price limit critics claim that price limits cause higher volatility levels on subsequent days (volatility spillover hypothesis), prevent prices from efficiently reaching their equilibrium level (delayed price discovery hypothesis), and interfere with trading due to limitations imposed by price limits (trading interference hypothesis). Empirical research does not provide conclusive support for either positions. We examine the Tokyo Stock Exchange price limit system to test these hypotheses. Our evidence supports all three hypotheses suggesting that price limits may be ineffective.     

基金经理更换、股票联动与股票价格

基金经理更换打破了基金共同持股投资组合中股票的关联性,降低了股票收益率相关性,进而影响了股票价格。本文基于基金共同持股和基金经理更换构建了对冲投资组合,获得0.1%的日超额收益率。基金投资组合中股票收益率相关性能够解释这种超额收益率,本文发现基金更换经理后,新基金经理重建投资组合,打破了原投资组合中股票间的关联,股票收益率相关性减弱,基金共同持股程度高的股票价格受到了更大影响。基金的被动流动性冲击不能解释本文的发现。本文的研究表明基金经理变更等基金管理行为通过股票收益率相关性对股票价格产生了重要影响。     

Effects of Preferred Stock Re-rating on Common Stock Prices: Further Evidence

This study examines the price reactions of common stocks to changes in preferred stock ratings, with focuses on firms with less information available in the market as well as on firms with a relatively larger proportion of preferred stock financing. Emphasis on differential information and the relative size of preferred stocks across firms provide a more powerful test of the effect of rating changes on stock prices. Contrary to previous studies that report no price effect on common stocks due to preferred stock re-ratings, these results show that for low-information firms and for firms with a larger proportion of preferred stocks in their capital structure, a preferred stock rating downgrade exerts significant negative price effect on common stocks during the two-day announcement period. Our findings also have implications for future studies of other firm-specific events such as security offerings, stock repurchases, and convertible calls.     

The effect of price limits on intraday volatility and information asymmetry

We investigate the effect of price limits on intra-day volatility and information asymmetry using transactions data from the Taiwan Stock Exchange. Proponents of price limits argue that they provide an opportunity for investors to reevaluate market information and make more rational trading decisions. We identify three different limit hits – closing, single, and consecutive – and hypothesize that only the consecutive limit hits are likely to provide such an opportunity, namely, to counter investor overreaction (volatility hypothesis) and to enhance information revelation (information asymmetry hypothesis). Our empirical evidence supports the volatility hypothesis. Our findings generate important policy implications for stock markets that have price limits.     

Stock price synchronicities and speculative trading in emerging markets

The literature suggests that the strong price synchronicity observed in emerging markets is driven by the lack of firm-specific information acquisition. This paper extends previous studies by focusing on the question of whether investors’ speculative trading behavior or market conditions make the synchronicity in emerging markets more pronounced. Our results indicate that the propensity to engage in speculative trades and a low level of linkage with the world market lead to greater stock price synchronicity. These results are consistent with the hypotheses that it is difficult to price firm-level fundamentals in a speculative market where noise trades prevail, and that less weight is attached to firm-specific fundamentals in pricing stocks in a more segmented market. The price synchronicities are largely found to be stronger in bearish markets, a finding consistent with the hypothesis that investors have increased loss aversion during bear markets, which further limits informed arbitrage.     

交易限制与股票市场定价效率——基于创业板涨跌幅限制放宽的准自然实验研究

本文基于2020年8月24日创业板涨跌幅限制由10%扩大到20%这一政策变化建立准自然实验,从市场层面与公司事件层面探讨交易限制放宽的外生冲击下市场定价效率的变化。研究发现,涨跌幅限制放宽政策实施后,股票价格能更灵敏地反映公开市场信息,更多地包含公司层面特质信息,整体市场定价效率显著提升。进一步研究表明,涨跌幅限制放宽有效缓解了交易干扰问题,避免了过度交易行为延后,缓解了波动性外溢与价格发现延迟。异质性分析表明,无论是市场层面定价效率改善,还是事件层面波动性外溢、价格发现推迟与交易干扰问题的缓解,均在低信息透明度公司中更为显著。本文研究发现为验证涨跌幅限制会抑制股票市场定价效率的理论提供了直接经验证据,同时为推广完善市场化交易制度提供了有益启示。     

The Conditional Performance of REIT Stock Repurchases

This paper uses a conditional performance measure to test whether real estate investment trust (REIT) managers announcing stock repurchases have private information about their firms' prospects. We use stock price to condition for public information and measure the managers' implied private information by the covariance between repurchase size and subsequent stock payoffs (or operating performance). Results show that managers have private information but mostly with respect to long-term as opposed to near-term payoffs. We also find that repurchase size is positively related to a stock's idiosyncratic return volatility, perhaps because noisy stocks deviate farther from fundamental value, offering informed managers larger profit potential. JEL Classification G12 G14 G35     

Volatility increases Subsequent to NYSE and AMEX Stock Splits

The post-split increase in daily returns volatility is less for AMEX stocks than for NYSE stocks. The exchange trading location is a significant factor in explaining the volatility shift even after stock price and firm size are considered. Furthermore, when measured on a weekly basis, there is no increase in AMEX stocks' returns volatility. These results suggest that measurement errors created by bid-ask spreads and the 1/8 effect, and also one or more of the elements that make the NYSE different from the AMEX, explain why the estimated volatility of daily stock returns increases after the ex split date.     

Media Coverage and the Cross-section of Stock Returns

By reaching a broad population of investors, mass media can alleviate informational frictions and affect security pricing even if it does not supply genuine news. We investigate this hypothesis by studying the cross-sectional relation between media coverage and expected stock returns. We find that stocks with no media coverage earn higher returns than stocks with high media coverage even after controlling for well-known risk factors. These results are more pronounced among small stocks and stocks with high individual ownership, low analyst following, and high idiosyncratic volatility. Our findings suggest that the breadth of information dissemination affects stock returns.     

An empirical investigation of trading volume and return volatility of the Taiwan Stock Market

This study examines the Mixed Distribution Hypothesis (MDH) using 5-min interval stock returns of the Taiwan Stock Index (TSI). Startlingly enough, the persistence of stock volatility remains dominant after the stochastic mixing variable was included in the variance equation. It implies that the MDH cannot explain away the ARCH phenomenon. We have found that the composition of participants (approximately 92% of participants are individual investors) in TSI is a major contributing factor to the persistent volatility. In addition, the existence of limits on price changes, to some extent, accounts for the persistence phenomenon. Similar results are also found for individual stocks in the sample. Interestingly enough, the explanatory power of trading volume exhibits a U-shaped pattern in explaining return volatility in Taiwan Stock Market.     

基本养老保险基金投资、股票收益率与股价波动性

以2017—2022年各季度基本养老保险基金投资数据为样本,考察基本养老保险基金投资对股票收益率与股价波动性的影响。结果显示：基本养老保险基金持股比例变化对股票未来收益率有一定预测效应,持股比例增加会加剧股价波动。异质性检验表明,被持股公司规模越大,持股比例变化对股票收益率的影响越不明显,对股价波动性影响的时滞性越强。对于短期持股而言,持股比例增加会加剧股价波动,而对于长期持股而言,持股比例增加有利于稳定股价。鉴于此,应继续推动基本养老保险基金全国统筹,进一步扩大其市场化投资规模、延长投资考核期限,提升基金可持续发展能力。     

Volume,volatility and information linkages in the stock and option markets

This paper examines the relationship between option trading activity and stock market volatility. Although the option market is uniquely suited for trading on volatility information, there is little analysis on how trading activity in this market is linked to stock price volatility. The bulk of the discussion tends to focus on whether trading activity in the stock market is informative about stock volatility. To analyze the information in option trading activity for stock market volatility, a sample of 15 stocks with the highest option trading volume is selected. For each stock, it is noted that the trading activities in the put and call option markets have significant explanatory power for stock market volatility. In addition, the results indicate that the call option trading activity has a stronger impact on stock volatility compared with that of the put options. Our results demonstrate that information and sentiment in the option market is useful for the estimation of stock market volatility. Also, the significance of the effects of option trading activity on stock price volatility is observed to be comparable to that of stock market trading activity. Furthermore, the persistence and asymmetric effects in the volatility of some stocks tend to disappear once option trading activity is taken into account.     

The Timing of Opening Trades and Pricing Errors

After demonstrating that a zero investment trading strategy that buys stocks with overnight returns below the market average and sells stocks with overnight returns above the market average earns more than 1% monthly profit, I demonstrate that this profit is greater for stocks that start trading more quickly than for other stocks. These results control for trading costs. The resulting pricing errors are a material portion of stock price volatility and suggest that a quick response to overnight information adds non‐information‐based stock volatility to stock prices.     

A Likelihood Ratio Test of Price Volatilities: Comparing Stock Index Spot and Futures

This paper uses three methods to estimate the price volatility of two stock market indexes and their corresponding futures contracts. The classic variance measure of volatility is supplemented with two newer measures, derived from the Garman-Klass and Ball-Torous estimators. A likelihood ratio test is used to compare the classic variance measure of price volatilities of two stock market indexes and their corresponding futures contracts during the bull market of the 1980s. The stock market volatilities of the Standard & Poor's 500 (S&P 500) and New York Stock Exchange (NYSE) indexes were found to be significantly lower than their respective futures price volatilities. Since information may flow faster in the futures markets than in the corresponding stock market, our results support Ross's information-volatility hypothesis. It was also noted that the NYSE spot volatility was lower than the S&P 500 spot volatility. If the rate of information flow and firm size are positively related, then the lower NYSE spot volatility is explained by the size effect. The futures price volatilities for the two indexes were insignificantly different from each other. With stock index spot-futures price correlations approaching unity, one implication of our results for index futures activity is that smaller positions in futures contracts may suffice to achieve hedging or arbitrage goals.     

ARE PRICE LIMITS EFFECTIVE? EVIDENCE FROM THE ISTANBUL STOCK EXCHANGE

There is considerable discussion about controlling volatility by imposing price limits on asset prices. We examine the effects of price limits on a stock market by testing the volatility spillover, delayed price discovery, and trading interference hypotheses in a leading emerging market, the Istanbul Stock Exchange, which has a unique market microstructure as related to price limits. Our results support the volatility spillover, delayed price discovery, and trading interference hypotheses. We also show price locks at limits provide significantly stronger evidence regarding the effects of price limits than limit moves only. Finally, price limits have a significant effect on the stock market, casting doubt on their effectiveness.