上市公司股票机构投资者羊群行为的经济效应研究

文章选择2012年第四季度到2018年第三季度深圳A股市场个股的净买入和净卖出的公募基金数量数据,采用LSV模型测算了机构投资者的羊群行为强度,分析机构投资者羊群行为的演变态势,并分析其对上市企业资本绩效和经营绩效的影响.结果表明:深圳A股市场的机构投资者羊群效应是存在的,呈现先下降后上升的趋势,卖方的机构投资者羊群行为高于买方.机构投资者羊群行为降低了企业股价收益率,但加大了股价波动,此外机构投资者羊群行为也显著降低了企业长短期财务绩效.结论表明现阶段我国机构投资者羊群行为未能起到"市场稳定器"的作用,也未发挥参与企业治理的功能.     

证券市场“羊群行为”的机理及研究方法

在阐述证券市场“羊群行为”内涵的基础上,分析了“羊群行为”的种类及其产生原因,并且对实证研究进行了总结,现有的对“羊群行为”的实证研究可分为两个方向:一是以股价分散度为指标,研究整个市场在大幅涨跌时是否存在显著“羊群行为”;二是以证券投资基金等特定类型的机构投资者为研究对象,通过分析它们的组合变动和交易信息来判断其是否存在显著的“羊群行为”。     

企业数字化转型抑制了机构投资者羊群行为吗

应用基于机器学习的文本分析方法，选取我国A股上市企业2010～2021年的数据，考察企业数字化转型对机构投资者羊群行为的抑制作用。研究发现，企业数字化转型通过缓解信息不对称，显著抑制了机构投资者羊群行为。机制检验表明：企业数字化转型提高了企业的信息披露水平，有助于外部投资者掌握更充分的信息，进而抑制机构投资者羊群行为；企业数字化转型引发了分析师和大众媒体的关注，缓解了投资者的信息不对称，进而抑制机构投资者羊群行为。区分买方市场和卖方市场发现，企业数字化转型对卖方市场上机构投资者羊群行为产生的抑制作用更强。异质性分析表明，企业数字化转型对机构投资者羊群行为的抑制作用在高科技企业、中小型企业、机构投资者持股比例较低的企业中表现得更加明显。     

我国证券投资基金的羊群行为分析

目前,受我国政府宏观调控以及美国次级债等问题的影响,证券市场正在经历大的波动。很多投资者在进行投资活动时,存在着大量的非理性行为,“羊群行为”就是其表现之一。现有对“羊群行为”的实证研究可分为两个方向：“一是以股价分散度为指标,研究整个市场在大幅涨跌时是否存在羊群行为。     

机构投资者对股价操纵影响的机理分析

随着我国资本市场的快速发展,股票操纵手段日益隐蔽,机构投资者在股票市场中的地位越来越重要。国家出台相关措施大力发展机构投资者,以期能够发挥机构投资者的资金优势和信息优势,并遏制股票市场上屡禁不止的股价操纵行为。但不可否认的是,这些机构投资者同样具有非理性行为,他们的出现不但没有有效遏制股价操纵行为,反而给股市带来了一些列不稳定的因素,使股市变得更加不稳定。因此,本文分析国内外学者关于机构投资者对股价操纵的影响,并对其影响机理进行分析,提出相应的股价操纵防范措施,以期能够提高我国股市的稳定性。     

羊群行为及其对金融市场的影响综述

系统概述金融市场中的羊群行为,分析羊群行为的分类、羊群行为对市场的影响、羊群行为的模型以及羊群行为的检验方法,并且总结国内股市关于羊群行为的实证研究,希望对我国的投资者和监管机构有一定的益处。     

游戏驿站股票现象的解析与启示——基于行为金融的视角

2021年1月的最后一个交易周,在游戏驿站这只股票上散户们一致买入,历史性地完胜做空机构,成为媒体报道的焦点。散户们的这种投资行为是否理性?是什么导致了该现象的产生?本文首先回顾游戏驿站现象的缘起和过程;其次介绍基于投资者情绪的行为金融学相关理论,指出社交媒体不仅快速高效地进行信息交互,而且导致投资者情绪的交叉感染;然后依据过度自信、情感情绪、羊群行为、代表性偏差等行为金融学理论,诠释机构投资者与散户在游戏驿站股价博弈中的非理性行为;最后总结本文的结论和启示。     

短期内机构投资者行为和股票价格的互作分析

研究短期内机构投资者行为与不同规模公司股价的相互影响.在机构投资者对股价的影响方面,阐释并论证了机构持股比例增量与当日股价的正相关关系,指出机构对大盘股的影响强于对小盘股的影响.机构资金流入(流出)的定性信息本身对股价上升(下降)有额外的促进作用;相对于撤资而言,股价对机构的注资行为更敏感;而对小盘股,该不对称性更加明显.此外,当日收益率和前三天内的机构资金流入存在负相关关系,且该种负关系在大盘股中的表现比在小盘股中更为明显.在股价对机构投资者行为的反馈作用方面,以实证结果阐明了股价上升(下降)的信息本身可对机构行为有缓冲作用,且该作用对小盘股影响大于对大盘股的影响.研究显示,在短期内机构更倾向于动量交易,这在小盘股中尤为明显.三天前收益率对当日机构行为的影响颇为明显,且与一天前的收益率的影响力相当;相对而言,两天前收益率对机构行为的影响不甚明显.     

机构投资者持股与股价崩盘风险:基于内外部治理视角

文章选择2010—2017年中国A股上市企业数据,分析了机构投资者持股水平对股价崩盘风险的影响和不同类型机构投资者对股价崩盘风险的影响差异,并基于内外治理视角探讨了股权集中度和媒体关注度在其中发挥的调节作用.结果表明:机构投资者持股显著加大了股价崩盘风险,交易型机构投资者持股对公司的股价崩盘风险的正向影响比稳定型机构投资者大;股权集中加剧了机构投资者持股对股价稳定的消极影响,媒体关注平滑了机构投资者持股对股价稳定的消极影响.     

会计稳健性、机构投资者异质性与股价崩盘风险——来自中国A股上市公司的经验证据

股价崩盘风险已经对资本市场的健康发展产生了重要影响。以中国资本市场2008年至2013年A股上市公司为样本,实证检验了会计稳健性与股价崩盘风险的关系,并考察机构投资者异质性对二者关系的影响。研究结果表明,会计稳健性能够显著降低股价崩盘风险。进一步考察机构投资者异质性,在划分为稳定型与交易型的基础上,发现稳定型机构投资者会增强二者的负向关系,交易型机构投资者则削弱二者的负向程度。文章的研究结论为防范股价崩盘风险、构建平稳有序的资本市场提供了一定的借鉴意义。     

Factors affecting institutional investors to add crypto-currency to asset portfolios

As crypto-currency has been gained great attention in financial market, it becomes more popular among institutional investment managers’ portfolios. Thus this research makes a pioneering study to investigate the role of crypto-currencies in PE company portfolios and factors affecting the institutional investors’ investment intention in order to enhance the reliability of their investment products. Data were obtained from 253 multinational PE company investment managers who have bought and used crypto-currency. The findings suggest not only important roles or drivers but also the moderating roles of innovativeness on relationships between the investment intention and its antecedents. It suggests that price volatility doesn’t lower institutional investors’ confidence as long as the market can offer timely and accurate price change information to meet investors’ price consciousness. The result also identifies that crypto-currency with high familiarity and trust can be well-suited in institutional investors’ portfolios.     

自媒体帮助控股股东在定向增发中获利了吗？

考察了上市公司控股股东如何利用自媒体信息披露在定向增发融资中调节股价的变化,从而获取额外收益的过程。研究发现：控股股东为使定向增发融资顺利进行,倾向于在定向增发准备期频繁发布自媒体信息,以抬高股价吸引外部投资者关注,并且当发行对象不包括控股股东时,通过发布自媒体信息来抬高股价的行为会更加显著;而在定增新股定价期间,定向增发对象包括控股股东的上市公司却会显著减少自媒体信息发文数量,以压低股票价格,帮助控股股东以较低对价购入定增股票。进一步分析发现：上市公司中机构投资者持股对控股股东定价期间压低股价的行为具有显著抑制作用。从自媒体信息披露这一崭新视角切入,证实了我国上市公司控股股东在定向增发过程中既有通过自媒体信息披露使定向增发吸引关注、满足融资需求的动机,又有利用自媒体信息披露降低控股股东参与定向增发的成本、对自身进行利益输送的动机;而机构投资者能够有效监督这一过程中大股东的利己行为。研究结论为加强对上市公司在定向增发中信息披露的监管,保护中小投资者利益提供了有益的启示。     

C2C电子商务中羊群效应的研究

羊群效应是一种广泛出现的社会现象,在日常决策、金融、商贸领域都广泛存在。发生羊群效应时,人们往往会追随他人的选择而忽略自有的信息。信息瀑布理论解释了羊群效应产生的机制,根据该理论,电子商务具备产生羊群效应的条件。为了验证电子商务中羊群效应是否发生,文章对淘宝网一商品市场的全部39个商品的销售情况进行了实证研究,通过多元回归分析,证明了历史销量排名对今日市场份额有正作用,从而证实了羊群效应的存在。     

Influence of institutional investors' participation on flipping activity of Malaysian IPOs

This paper examines the influence of institutional investors’ participation on flipping activity of Malaysian IPOs. Measured as the percentage of trading volume on the first trading day against the total number of shares offered, flipping is the quickest way to gain huge profits from IPOs. However, excessive flipping activity has significant potential to create artificial downward pressure on the price of IPOs. One way to reduce such an adverse effect is by strategically allocating a larger proportion of new shares to institutional investors. This is because institutional investors are normally assumed to be long-term investors. As such, they are less likely to flip their allocated IPOs in the immediate aftermarket. The long-term investment argument is consistent with institutional investors’ preference for a steady income stream in the form of dividends. Drawing upon this argument, the greater participation of institutional investors during an IPO is expected to be an effective strategy to control aggressive flipping activity. The Malaysian IPO market offers an excellent opportunity to examine this hypothesis because data regarding the allocation of new shares to institutional investors can be traced conveniently through a type of IPO referred to as “private placement”. Based upon an examination of 248 IPOs listed on Bursa Malaysia between January 2000 and December 2012, this study finds a negative relationship between institutional investors’ participation and flipping activity. This result lends strong support to the argument concerning the effectiveness of institutional investors’ participation in controlling flipping activity in the Malaysian IPO market.     

Institutional investors' attention to environmental information,trading strategies,and market impacts: Evidence from China

Using a large proprietary database of intraday high‐frequency trading, we investigate the trading strategies of institutional investors in dealing with the negative environmental event disclosure of listed companies and their impact on markets, aiming to reveal the mechanism of the lack of “green efficiency” in China's capital market from the perspective of institutional investors. The results show that institutional investors react to negative environmental events prior to the announcements, indicating premature information leakage in the market; in addition, their trading behaviors mitigate the immediate effect of negative environmental event announcements on stock price. After the event is disclosed, institutional investors engage in short‐term selling and long‐term buy and hold. This trading strategy undermines the irrational selling of individual investors in the event of disclosure, short‐term decline in stock price, and long‐term reversal of market overreaction. In a China context, institutional investors generally take environmental information into consideration. However, they fail to recognize the long‐term value effect of negative environmental events and instead cater to trading strategies towards market volatility.     

机构投资者持股与企业短贷长投：抑制还是促进？

利用2007—2019年A股上市公司的年度数据,针对中国上市公司短贷长投这一现象,研究了机构投资者在其中发挥的作用。研究发现,机构投资者持股使得上市公司进行了更多的短贷长投,且该效应在非国有企业中更加明显。进一步研究发现,只有当机构投资者为非独立型机构投资者时,这种促进作用才显著,且机构投资者数量同样加剧了企业短贷长投。从短贷长投视角考察机构投资者对上市公司债务风险的影响,为治理上市公司短贷长投行为和进一步推动独立型机构投资者发展、完善机构投资者监管提供了参考。     

The impact of investor structure on stock price crash sensitivity: Evidence from China's stock market

Stock price crash sensitivity refers to the conditional probability of a stock crash when the market collapses. It focuses on individual stocks' sensitivity to the market crash and can affect stock pricing significantly. Although the crash sensitivity of China's stock market is very high as a whole (Weigert, 2016), different individual stocks show varying degrees of crash sensitivity. This paper, adopting the perspective of institutional investors, explores the reasons for the difference in crash sensitivity in China's stock market, and finds that: First, institutional investors' shareholdings is positively related to firms' stock price crash sensitivity. However, after dividing institutional investors into professional (represented by financial institutions) and non-professional institutional investors (represented by general legal persons), we find that only professional institutional investors' shareholdings is negatively related to firms' stock price crash sensitivity. Second, the impact of professional institutional investors on the crash sensitivity is influenced by stock liquidity and media sentiment: when the stock liquidity of listed companies is good or the media sentiment is strong, the negative impact of professional institutional investors on the crash sensitivity is accordingly high. This paper, by highlighting the investor structure, attempts a pioneering exploration of the influencing factors of the difference in stock price crash sensitivity in China. Our empirical results enrich research on stock price crash sensitivity and the heterogeneity of institutional investors. They can also serve to guide regulatory authorities' development of institutional investors and efforts to maintain market stability.     

公众注意力影响买入行为吗？——基于投资者行为的分析

公众注意力衡量了一只股票受投资者关注的广泛程度。本文分析了公众注意力对不同类型投资者买入行为的影响,发现小投资者更倾向于买入引起他们注意的股票,中大类型投资者没有明显与注意力相关的买入行为,机构投资者则表现出了与公众注意力相关的策略性行为。小投资者的这种特性使得他们更容易成为市场操纵的受害者,对此本文提出了相应的政策建议。     

Are institutional investors colluding with manipulators?

This paper examines the trading behavior of institutional investors in Taiwan before, during, and after a manipulation event and determines whether institutional investors benefit from their trading behavior during the period from the year 2000 to 2020. We find that stocks with a low turnover and small market capitalization are the main targets of price manipulators. In addition, the stock price of manipulated firms increases from the start date of the manipulation event, peaks at the end of the event, then falls after the event. Foreign institutions collude with manipulators to exaggerate stock prices for self-benefit. In contrast, securities dealers counter the trading behavior of manipulators and act as market stabilizers, causing them to suffer losses. Moreover, foreign institutions earn higher returns on stocks of manipulated firms with a low turnover during and soon after manipulation; however, they earn a higher return on stocks of manipulated firms with a high turnover in the long run after manipulation.