全流通市场中大股东交易的影响因素研究——基于股权结构的视角

全流通市场中的大股东交易问题日益成为关注的焦点。以2007年至2010年A股市场大股东交易作为研究对象,验证了股权结构对不同类型大股东交易行为的影响。研究结果显示控股股东净购买率与股权集中度显著负相关,与股权制衡度显著正相关;而非控股股东净购买率与股权集中度显著正相关,与股权制衡度显著负相关。这说明现有股权结构对控股股东和非控股股东交易行为的影响存在显著差异,而这种显著差异又将导致未来上市公司股权结构发生明显变化。     

内幕交易、股价信息含量与投资非效率

本文以上市公司年报窗口期的累计异常换手率作为内幕交易的衡量指标,并根据A股公司2010-2017年数据考察了内幕交易对公司投资效率的影响。实证结果表明,内幕交易会抑制外部投资者的信息搜集活动,降低股价信息含量,进而降低公司的投资效率。进一步研究结果表明,机构投资者的持股比例、证券分析师的关注度、地区市场化程度、公司研发强度、CEO的经验及公司融资约束这六个因素会影响内幕交易与投资效率间的关系。     

多个大股东、盈余质量与企业投资效率

从股东合谋的视角和股东之间存在协调成本的视角出发,探讨多个大股东对投资效率的影响。选取2015-2021年中国A股上市公司为初始样本,通过固定效应模型对此进行检验。实证结果表明,存在多个大股东对投资效率具有正向影响,并且多个大股东的数量也正向影响投资效率,盈余质量在两者关系中起到部分中介的作用;在进一步的研究中发现,多个大股东主要是改善了企业的投资不足。研究结论对于如何提高企业投资效率与优化治理结构提供有益参考。     

正反馈交易、市场效率与流动性黑洞——基于日内分笔交易数据的实证研究

金融危机爆发以来,全球资本市场流动性出现紧缩;中国市场波动幅度增加,多只股票出现流动性黑洞,市场效率显著降低。本文通过向量自回归(VAR)分析,发现投资者在不同程度上采用了正反馈交易策略。进一步地,对存在正反馈交易和不存在正反馈交易的数据分别进行多方面的比较分析,文章发现正反馈交易者显著地降低了市场的效率;通过对收益率序列和委比序列进行向量自回归分析,发现正反馈交易降低了市场的多样性,更容易产生流动性黑洞。     

基于社会网络传递视角的内幕交易行为研究

依法从严打击内幕交易是我国金融监管的重要任务,也是推动资本市场高质量发展的重要保障。本文手工收集2007—2020年我国证监会公布的内幕交易行政处罚书中涉及的内幕信息和内幕交易数据,考察我国股市内幕交易的行为特征。研究发现：(1)从中美股市对比看,我国股市中消极型内幕信息占比更低,内幕信息泄露时间更长,内幕信息泄露期间和信息公告日的收益率绝对值更低。此外,我国股市中依托家人关系传递内幕信息的比例高于美国。(2)公司外部人尤其以朋友关系传递的内幕信息致使更高的内幕交易规模和收益率。(3)内幕交易显著提高了内幕信息泄露期间相关方的股票收益率。本文丰富了内幕交易学术文献,也为我国监管机构提升内幕交易监管效率提供了有益借鉴。     

大单交易行为在中短期内是否表现出信息优势

通过检验上证A股市场中大单交易者完成大单交易后在检验期内的日平均回报率是否大于0,从而说明大单交易者是否具有信息优势.研究表明:大单交易者不具有信息优势.     

关联交易还是信息优势?——基于国内证券投资基金重仓股的分析

由于国内证券投资基金制度上的特殊性,与许多上市公司拥有同一大股东,这一"金字塔"结构造成证券基金可能同时存在利益输送式的关联性投资或信息优势导致的获利性投资。本文通过对2005年至2010年所有基金公司季度重仓股持股数据的研究发现基金公司对其重仓股的交易的确存在着关联交易或信息优势的可能性。基金公司倾向于超买非关联性股票,这些股票在下一季度的收益与超买行为显著正相关,这表明基金公司可能拥有信息优势。对于关联性股票,基金公司则倾向于超卖,但下季股票收益与超卖行为并不显著相关,这可能是关联交易与信息优势两种可能性共同作用的结果。总体上看,国内基金的投资行为更多地由于信息优势所致。     

夜盘交易与期货市场效率

基于实施夜盘交易前后SHFE的铝期货交易数据,本文运用R/S分析法、共同因子模型等方法从流动性、信息效率及定价效率角度研究夜盘交易制度对期货市场效率的影响。结果发现:夜盘交易的开展,使得铝期货价格的波动性明显下降,市场的流动性显著提升;在夜盘交易后,铝期货价格时间序列的长期记忆性显著下降,历史信息对铝期货价格的影响明显减弱;由于夜盘交易的开展,铝期货市场在长期对现货市场具有显著的引导作用,且在价格发现过程中的贡献也明显扩大。这表明,夜盘交易的开展改善了铝期货市场的流动性、定价效率及信息效率,对期货市场效率的提升具有重要意义。     

交易透明度对证券场外交易信息效率的影响

黑池交易系统(Dark Pools)是美国近年发展较快的非公开交易平台,其信息透明度较低,可提供匿名交易的服务,并由此实现信息的非公开传递。通过扩展后验信念收敛速率的模型来描述不同交易透明度下场外市场的信息显示速率,发现私人信息与公共信息共存有利于信息更快地显示,因而私人信息渠道与公共信息渠道共存有利于提升信息效率,由此解释了非公开交易平台的价值,也为我国场外市场的分层发展提供可行建议.     

Detecting Information from Directors' Trades: Signal Definition and Variable Size Effects

There have been three empirical studies examining the share price reaction following trades by directors of UK companies (King and Poell, 1988; Pope, Morris and Peel, 1990; and Gregory, Matatko, Tonks and Pukiss, 1994). All three of these UK studies used different definitions of 'buy' and 'sell' signals resulting from the transactions of directors and employ different controls to detect the presence of any 'size effects'. We investigate whether the signal definition explains the different conclusions drawn by these earlier studies, and examine whether or not any observed abnormal returns are explicable by the small companies effect. We also investigate trading strategies based on holding a long portfolio of shares purchased or a short portfolio of shares sold by directors held until the end of the study period or until a 'reserving event' (e.g. a sale following a purchase by director[s] is observed).     

Empirical Evidence on the Role of Trading Suspensions in Disseminating New Information to the Capital Market

Abstract:  This paper examines the effect of temporarily suspending the trading of exchange-listed individual stocks. We evaluate whether regulatory authorities can successfully use the mechanism of trading suspension in forcing companies to disclose new and material information to the capital market. Previous studies on trading suspensions mainly concentrate on North-American stock markets and find conflicting results. This study utilizes a new data set comprising of firms listed on Euronext Brussels – an important segment of Europe's leading cross-border exchange. Our results show that suspension is indeed an effective means of disseminating new information. Stock prices adjust completely and instantaneously to the new information released during trading suspensions. We also observe a significant increase in trading volume with the reinstatement of trading. On the other hand, we do not find support for the claim that trading suspensions increase the volatility of stock prices. Overall, our results show the efficacy of trading suspensions in disseminating new information.     

证券交易的透明度与信息揭示制度：理论综述

证券交易过程中，交易信息的发布、扩散和传递方式对于各类市场参与者非常重要。目前关于信息揭示制度和交易透明度对市场运行效果的影响尚存在许多争议。本文讨论了交易透明度的含义、研究者和市场机构对于交易透明度的争论、交易透明度与市场绩效的关系，以及不同交易透明性的市场之间的竞争等问题，系统总结了目前与证券交易透明度和交易信息揭示有关的理论观点，以期把握交易信息揭示程度对市场产生的影响，以及由此引起的交易透明度对市场的运行效率产生的影响。     

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 Exchange Reforms and Market Efficiency: the Italian Experience

This paper examines whether the reforms introduced by the Italian Stock Exchange from 1991 to 1994 (creation of specialised intermediaries, obligation to trade on the official markets, screen-based trading and cash settlement) did increase market efficiency. The issue is addressed using both the traditional information efficiency model, which tests market efficiency by verifying the predictability of prices conditional on some information subset, and a microstructure approach that measures efficiency as the distance of the price movements from their efficient components, represented by a random walk process. The joint analysis of daily and intraday data on prices and volumes validates the hypothesis that most of the reforms have increased market efficiency over the sample period, except for cash settlement, which appears to have substantially reduced it.     

Relation Between Predisclosure Information Asymmetry and Trading Volume Reaction Around Quarterly Earnings Announcements

This study investigates the effects of differences in predisclosure information asymmetry on trading volume reaction during quarterly earnings announcements. The analyses show that trading volume reaction to quarterly earnings announcements is positively related to the level of predisclosure information asymmetry and to the magnitude of the price reaction to the announcements. These results are consistent with Kim and Verrecchia's (1991a) theoretical trading volume proposition, and with Atiase and Bamber's (1994) tests of the proposition based on annual earnings announcements. This study also provides evidence on the relation of predisclosure information asymmetry and trading volume before and after quarterly earnings announcements.     

从国际经济学理论视角看企业竞争优势——兼议国际经济学优势思想的演进

本文通过回顾和分析国际经济学中国际贸易理论和国际直接投资理论优势思想的发展和]进,说明了理论研究可以通过对各种市场结构的细分,把优势分析引入到企业内部,并通过对分工、市场结构与交易费用之间的矛盾关系的深入研究,探讨内生优势与外生优势之间的对立统一关系,而企业竞争优势的培育则是一个建立在企业自身独特能力基础上的、综合利用企业内外部各种比较优势的动态累积发展过程。     

竞争优势--企业竞争力演绎的核心

文章通过竞争优势的逻辑演绎过程,揭示了企业制胜秘诀,这就是只有掌握了持续竞争优势,才能获得国际竞争力,才能在市场竞争中处于不败之地.     

The Effect of Trading Halts on the Speed of Price Discovery

Trading halts are aimed at reducing information asymmetry by granting investors the opportunity to reassess trades upon arrival of new, substantial information. This study is the first to address the efficiency of the price discovery process with respect to time, i.e., the speed of adjustment to new information. A unique database allow us to conduct an event study analysis and measure the impact of trading halts on price discovery while controlling for content, operational and value effects. We find that information dissemination following trading halts is over 40% faster and that abnormal trading activity is positively related to the speed of price adjustment.