企业控制权转移的短期与长期财富效应

在我国控制权市场日益发展的今天,讨论控制权转移对目标企业价值的影响,了解控制权市场效率,有着十分重要的意义。本文以我国证券市场沪、深两市A股市场在2006-2012年间发生控制权转移的上市公司为基础,利用事件研究法与购买并持有超额收益法进行研究。结果表明,从短期市场反应来看,CAR显著为正,控制权转移给目标企业带来了显著为正的财富效应。从长期来看,控制权转移企业的市场表现优于所选取的对比企业,BHAR显著大于0,控制权转移事件在长期增加了企业股东的财富,为企业创造了价值。     

定向增发、控制权变动及其信号传递效应

 当公司再融资引起股权结构显著变动时,其必然会对公司控制权配置、竞争和转移产生重要影响,这种影响传递到资本市场会使公司股价发生相应波动。这种效应在股权高度集中公司更为明显,因为大股东是公司的实际控制人,大股东股权进而公司控制权变动传递了公司经营管理的内部信息。采用事件研究法,本文研究发现定向增发在我国具有正的公告效应;但是,定向增发对大股东控制权的影响不同其公告效应也不同：使得大股东控制权发生转移的定向增发其AAR和CAR最大,控制权强化类定向增发居次,控制权弱化类最后。可见,我国上市公司定向增发传递出了明确的公司控制权变动信号,彰显了大股东控制在上市公司中地位突出的治理角色。     

Directional Add-issuance, Change in Corporate Control and Its Signal Effect

当公司再融资引起股权结构显著变动时,其必然会对公司控制权配置、竞争和转移产生重要影响,这种影响传递到资本市场会使公司股价发生相应波动.这种效应在股权高度集中公司更为明显,因为大股东是公司的实际控制人,大股东股权进而公司控制权变动传递了公司经营管理的内部信息.采用事件研究法,本文研究发现定向增发在我国具有正的公告效应.但是,定向增发对大股东控制权的影响不同其公告效应也不同:使大股东控制权转移类定向增发其AAR和CAR最大,控制权强化类定向增发居次,控制权弱化类最后.可见,我国上市公司定向增发传递出了明确的公司控制权变动信号,彰显了大股东控制在上市公司治理中的突出地位.     

信息性交易概率分解与买卖价差研究

本文首先将信息性交易概率（PIN）分解为个股信息性交易概率（PINID）和市场信息性交易概率（PINM）：利用2003年7月至2004年6月高频分笔数据，计算出上证50样本股的周PINID．发现PINID在PIN中占有大部分的比重，得到样本股的平均PINID为0．1052。其次，本文运用非参数检验验证了随着成交量增加，PINID显著减小。最后，在考虑PIN和PINID下，对买卖价差的影响因素进行研究。研究表明，虽然PIN对买卖价差有着显著的正向影响，但仅其中的PINID部分才是决定因素。这也验证了PIN分解的意义。此外，波动率和流通股比例均对买卖价差有着显著的正向影响，而股票价格、成交量和换手率的影响则不显著。     

对沪市印花税调整的经济分析

流动性衡量理论基础 在已有的衡量流动性的方法中，有价格法，主要用买卖价差来衡量个股的流动性；交易量法，应用得最多同时也为广大投资者所熟悉的是换手率。买卖价差衡量流动性的局限在于对交易规模不敏感等多个方面；而换手率忽略了价格变化的影响，而价格变化往往是衡量流动性的最主要的因素之一。那么我们可以把价格法和交易量法结合起来，建立价量结合的新的衡量流动性的指标。     

广东省上市公司控制权转移对公司治理影响的研究

股权结构是公司治理的产权基础,当企业的控制权发生转移,公司治理机制将会发生变动。本文以2004年标的为上市公司股权(标的属广东省)且控制权发生转移的股权交易案为研究样本,旨在分析上市公司控制权转移对公司治理的影响。因并购主体产权性质的差异性,控制权转移对公司治理的影响在角度与程度上各不相同。总体来说,控制权转移将促进公司治理主要在弱化内部人控制、行政干预减少及职业经理人市场的形成三个方面得以优化。     

投资者保护、金字塔结构与控制权私有收益

本文以沪深两市A股2004年-2007年度非流通股交易发生控制权转移公司为样本,基于投资者保护角度研究金字塔结构与控制权私有收益的关系。研究发现,两权分高度、金字塔结构控制层级、控制链条及其复杂程度与控制权私有收益显著正相关,金字塔结构实质上成为控股股东获取控制权私有收益的传送带;进一步检验发现,投资者保护环境的改善在降低控制权私有收益的同时,还能抑制金字塔结构与控制权私有收益的正相关性。     

公司成长能力、股权制衡与控股股东的控制权私利

通过对2005—2009年沪深两市发生了控制权转移的上市公司的研究,从公司成长能力和股权制衡度两个方面分析了控股股东的控制权私利行为。研究表明：（1）公司的成长能力对控股股东的控制权私利有显著的影响,并且两者成正相关关系;（2）国有控股公司存在更高的控制权私利水平,但随着企业成长能力的提高,民营企业的控制权私利比国有控股公司增长更快;（3）股权制衡度对控制权私利水平有抑制作用。     

中国股市交易量波动率和交易量相关性关系的实证研究

本文以沪深股票市场为研究对象,从预期和非预期交易量与价格变动之间的相关关系、交易量与市场波动间的动态关系等角度,深入分析我国证券市场的量价关系。针对原始交易量序列进行了分离,并引入EGARCH模型对交易量与收益率条件波动间的动态关系进行了检验,研究发现:中国股票市场上交易量和价格之间存在显著的正相关关系,交易量中引致依存关系的主要部分是信息交易量,这说明中国股票市场确实包含价格变化相关的重要信息;我国股市中收益率的波动存在杠杠效应,但并不十分明显,这可能与我国股市之前还不允许进行卖空交易、投资者的借售行为,以及政府对股市的干预有关;量价关系在统计意义上显著正相关,但依存度较弱,这意味着投资者不能完全依赖于技术分析,而只能将其作为辅助分析。     

股权激励的市场反应及其内幕交易的实证研究

文章以2008年1月份前推出股权激励计划的67家公司为样本,采用事件研究法,对股价在股权激励计划方案公布前后21个交易日是否存在超常收益率进行了实证研究。实证结果表明:样本公司的股票在事件窗口内存在显著为正的超常收益率,市场对这一事件作出了正向的回应,而且超常收益率主要是由消息公布产生的,不存在消息的提前泄露和内幕交易。     

The effect of information announcements on bid/ask spreads in the call options market*

Abstract. This study investigates changes in the call option market microstructure, as reflected in bid/ask spread changes, surrounding information release dates. The size of bid/ask spreads is not significantly changed by accounting earnings releases. The results indicate a significant increase in the bid/ask spread on the date of large price changes and a significantly increased number of insignificant changes in both actual and proportional bid/ask spreads surrounding earnings announcements and dates of large price changes. Significant increases in trading volume precede both types of information releases. Résumé. Cette étude examine les changements dans la microstructure du marché des options d'achat, tels que reflétés par les changements dans l'écart des cours acheteur et vendeur, autour des dates de publication d'information. La taille des écarts des cours acheteur et vendeur n'est pas sensiblement modifiée par la publication des bénéfices comptables. Les résultats montrent un accroissement significatif de l'écart entre le cours acheteur et vendeur à la date de changements majeurs des prix, et un accroissement significatif du nombre de changements négligeables à la fois des écarts de cours acheteur et vendeur absolus et relatifs, autour des dates de publication de résultats et de fluctuations de prix importantes. Des accroissements significatifs du niveau d'activité précèdent les deux types d'informations divulguées.     

Tick size change and liquidity provision on the Tokyo Stock Exchange

The Tokyo Stock Exchange (TSE) introduced a change in its minimum tick sizes on April 13, 1998, for stocks traded at certain price ranges. We investigate the liquidity and market quality of the stocks affected by the tick size change, using a unique and comprehensive tick-by-tick data. We find that the quoted spread (effective spread) declined significantly by 20 to 50 percent (by 24 to 60 percent) after the tick size change. Reductions in spread are greater for firms with greater tick size reductions, greater trading activity, and higher transitory component in the bid–ask spread. Although investors are more aggressive in posting quotes, there is no definite evidence of an increase in trading volume. Overall, our evidence is consistent with the hypothesis that the minimum tick size creates economic rents for liquidity providers, which is lowered upon tick size reduction. J. Japanese Int. Economies 21 (2) (2007) 173–194.     

Foreign exchange market intervention and price discovery

This paper studies the role of foreign exchange market intervention in the price discovery process of the USD–JPY market. Using the tick-by-tick bid and ask quotes from the Electronic Broking Services (EBS), we find that Japanese official intervention affects the relative contributions of bid and ask quotes to price discovery of the USD–JPY exchange rate. The empirical results show that bid quotes usually respond to information more promptly than ask quotes, as measured by information share on a daily basis. The asymmetry in price-discovery efficacy of bid and ask quotes, however, declines in magnitude on days in which Japanese monetary authorities intervene in the USD–JPY market.     

Earnings Announcements and Information Asymmetry: An Intra‐Day Analysis*

This paper examines the effect of earnings announcements on information asymmetry as perceived by specialists. We use changes in quoted bid‐ask spreads and depths (relative to the average value in the non‐announcement period) as proxies for changes in information asymmetry in the market. To our knowledge, we are the first to employ a model that captures the simultaneous nature of the specialists' choice of spreads and depths in reaction to earnings news. We provide evidence that spreads are wider and depths are smaller before the release of earnings announcements. We also find that changes to depths are greater for announcements of quarterly earnings than for announcements of annual earnings and changes to spreads persist longer into the post‐announcement period when announcements are made outside trading hours. These changes to spreads and depths persist when earnings announcements are made after trading hours.     

Disclosure Policy and Market Liquidity: Impact of Depth Quotes and Order Sizes*

This paper investigates the relation between disclosure policy and market liquidity. Our tests examine two key aspects of market liquidity, the effective bid‐ask spread and quoted depth, and how they relate to financial analysts' ratings of firms' disclosure policies. We introduce a method of combining order sizes and depth quotes to yield more precise estimates of effective spreads on trades likely constrained by quoted depth. We find that while firms with higher rated disclosures are charged lower effective spreads, they are also quoted lower depth, consistent with the notion that better disclosures reduce information asymmetry but also cause some liquidity suppliers to exit the market. Therefore, a simple examination of spreads and depths yields ambiguous inferences on the relation between disclosure policy and market liquidity. We resolve this ambiguity by estimating depth‐adjusted effective spreads, and find that firms with higher rated disclosures have lower depth‐adjusted effective spreads across all trade sizes. Consequently, our results reveal a robust inverse relation between disclosure ratings and effective trading costs. This implies that a policy of enhanced financial disclosure is related to improved market liquidity.     

The impacts of dual carbon goals on asset prices in China

In this paper, we study the impacts of dual carbon goals on asset prices in China. Using the speech of President Jinping Xi on 22 September 2020 as an event in which the dual carbon goals are formally announced, we find that stocks with green concept have superior performance in the post-event window relative to non-green stocks. In particular, a portfolio that longs green stocks and shorts non-green stocks can generate an average monthly return above 3%. The official announcement of dual carbon goals not only attracts attention of investors, resulting in higher institutional ownership and trading volume for green stocks, but also improves fundamentals for green stocks in the post-event window.     

Nonlinear and time-varying risk premia

Facing the puzzling risk-return trade-off, this paper proposes a new model for risk premia to capture nonlinear and time-varying features under the influence of trading volume. Using high-frequency data for the US stock market in Wharton Research Data Services' Trade and Quote database, our empirical findings suggest a significant nonlinear and time-varying contemporary relationship between return and realized volatility, ranging from positive to negative with an up-down-up pattern, summarized as follows. First, the contemporary relationship is positive on inactive trading days when the trading volume is smaller than usual, in which case traders may face no new information or event uncertainty. Second, the relationship is significantly negative when the trading volume is large on active trading days, in which case traders may be overconfident and behave in a risk-seeking fashion. Third, the risk premium tends toward zero during extremely abnormal trading days. Finally, low and high levels of trading volume have asymmetrical influences on risk premia, with a larger absolute value of risk premia for high levels of trading volume. Furthermore, the nonlinear changing autocorrelation of returns is insignificant from zero on normal trading days and most likely different from zero on abnormal trading days. These results provide explanations for the conflicts between financial theoretic and empirical studies.     

Trading volume theories and their implications for empirical information content studies*

Abstract. In this study we explore implications of extant trading volume theories for empirical information content studies. Using a simple general equilibrium model, we analyze and illustrate how trading volume reacts to information conveyed by an event. We show that a trading volume reaction to the release of an informational event is an increasing function of dispersion in belief changes among investors caused by information in the event, rather than belief changes per se. We also show that because of a possibility of no significant price change, a price effect study alone is not sufficient to accurately assess the information content of an event and a simultaneous volume effect study is necessary. Résumé. Les auteurs étudient les conséquences des théories existantes relatives au volume de titres négociés sur les études à contenu informationnel empirique. À l'aide d'un simple modèle d'équilibre général, ils analysent et illustrent comment le volume de titres négociés réagit à l'information transmise par un événement. Leur étude révèle que le volume de titres négociés par suite de la publication d'un événement informationnel croît en fonction de la dispersion dans les changements d'attitude chez les investisseurs attribuables à l'information que livre l'événement, plutôt qu'en fonction des changements d'attitude eux-mêmes. Elle démontre également qu'en raison de la possibilité qu'il n'y ait aucun changement de prix important, l'étude du comportement des prix risque de ne pas suffire à elle seule à évaluer avec précision le contenu informationnel d'un événement, et qu'une étude simultanée du comportement du volume de titres négociés s'impose.     

Intraday information efficiency on the Chinese equity market

Bid-ask spread is a direct measure of information asymmetry. As such, it can be used to evaluate information efficiency. In this paper, we show that both the quoted and effective spreads on the Shanghai Stock Exchange are extremely high at the open, decrease over the trading day, and experience a small rebound at the close. The spread decreases with share volume, daily trades, and market capitalization, but increases with average trade size. We further examine the beta using the unbiasedness regression from Biais et al. [Biais, B., Hillion, P., Spatt, C. (1999). Price discovery and learning during the pre-opening period in the Paris Bourse. Journal of Political Economy, 107, 1218–1248] and find that intraday prices are efficient and unbiased for more liquid stocks. This suggests that liquidity prompts information-motivated trading, which, in turn, improves information dissemination. Moreover, our findings indicate that small and medium trades are more likely to facilitate the formation of efficient prices at the open and close of the market, while large trades play a more important role during the other trading periods.