信息不对称、过度自信与正反馈交易——基于A股上市公司分笔交易数据的研究

本文利用中国股市中上市公司交易数据建立面板模型分别对个人投资者和机构投资者的正反交易行为与信息不对称和过度自信之间的关系进行分析。结果发现过度自信是导致个人投资者和机构投资者正反馈交易行为的重要原因：信息不对称虽然会降低投资者对于股票的需求,但是个人投资者在信息不对称的条件下更依赖历史收益率来做判断．所以信息不对称是个人投资者进行正反馈交易的重要原因,不过信息不对称却会抑制机构投资者的正反馈交易倾向。     

投资者个体的羊群行为:分布及其程度——基于分割聚类的矩阵化方法

现有研究的一个重要缺陷是无法精确地描述交易者个体羊群行为的分布及其程度,本文依据LSV及其衍生模型的思路,提出了基于分割聚类的矩阵化改进模型,并针对我国机构投资者,使用该改进模型对我国开放式基金的羊群效应进行了检验,结果发现:机构投资者个体的羊群效应分布呈现尖峰左偏的非标准形态;机构投资者在交易大盘股时的羊群效应比较明显;市场整体的羊群效应震荡增加;机构投资者个体的羊群行为会增加其投资时的收益和风险。     

我国机构投资者的“羊群行为”分析

机构投资者存在羊群行为已经成为学术界的共识。但是对我国股票市场机构投资者的羊群行为实质以及对证券市场稳定性有何影响众说纷纭。在研究机构投资者的羊群行为的实证基础上,本文阐述羊群行为存在的原因及其对证券市场的影响。     

中国股市个体投资者羊群行为影响因素分析

中国股市投资者表现出显著的羊群行为,心理因素是投资者羊群行为产生的主要原因,情绪、股票历史收益率和股票规模等也是影响投资者行为的重要因素。本文利用我国股市个体投资者交易数据,对影响投资者羊群行为的因素进行了实证研究,探讨了我国股市个体投资者羊群行为的特征。     

我国股票市场羊群行为收益的实证分析

当前国内对羊群行为的研究都集中在实证检验羊群行为的存在性以及羊群行为存在的原因解释方面,缺乏对羊群行为收益的分析,投资者的羊群行为能否给其带来收益应该是一个重要的问题.如果羊群行为能够给投资者带来收益的话,不管羊群行为是否加剧市场的波动,导致市场无效,甚至导致市场危机,遵循收益最大化的投资者都会采取这种行为.但是如果要实证研究投资者的羊群行为收益,我们又必须非常了解投资者的交易情况,而在当前的股票市场信息披露机制下,我们无法获得普通投资者具体的交易信息.根据目前证券法规的规定,基金在每个季度末必须公布其投资组合报告,报告中包括季度末的最后一天该基金持有的排名前十位股票.因此基于数据的可获得性,我们选取的研究对象是基金.     

我国证券投资基金羊群行为的实证研究

国外的研究显示，发达国家市场机构投资者的羊群行为并不十分明显。作为新兴市场主体的中国机构投资者在这方面的行为特征如何呢？本文使用经典的LSV方法以及Wermers扩展方法，对我国金融市场上以证券投资基金为代表的机构投资者交易行为进行了实证研究。结果发现，我国证券投资基金之间具有较明显的羊群行为，并具有以下特点：同时使用正负反馈操作策略；在流通盘较大和较小的股票上的羊群行为显著；成长型基金的羊群行为显著等。针对这些发现，笔者探究了羊群行为产生的原因，并提出了一些避免过度羊群行为的措施．     

陆港通制度对A股市场投资者正反馈交易行为影响研究

为考察陆港通制度对A股市场投资者正反馈交易行为的影响,本文基于Schuppli和Bohl(2010)的正反馈交易模型,以陆港通制度实施作为准自然实验,利用2010年4月至2020年9月间A股相关股票指数收益率数据为样本进行实证分析,结果表明:陆港通标的股票的投资者正反馈交易行为在政策实施后显著减少,且"追涨"行为较"杀跌"行为减少更为显著;陆港通制度的施行对正反馈交易行为的抑制作用在市值较低的股票中更显著;作用在短期内更为显著;2018年陆港通交易额度的扩容政策也对正反馈交易行为具有抑制作用。     

中国A股市场羊群行为的实证分析

以2010年至2018年A股市场数据为样本,实证检验了中国A股市场的羊群行为。研究发现:第一,沪深两市没有检测到显著的羊群行为,从公司规模和性质来看,上证超大盘市场和上证央企市场存在羊群行为,小规模和民企市场不存在羊群行为;第二,市场暴涨暴跌期间容易产生羊群行为,且上涨行情和下跌行情的羊群行为不对称,下跌时更容易产生羊群行为;第三,B股市场涨跌对A股市场投资者的羊群行为具有一定抑制作用。基于此,提出如下建议:一方面,对个人投资者而言,应当时刻保持风险意识,加强对投资理财知识的学习,避免盲目跟风,追涨杀跌;另一方面,对政府监管部门而言,积极开展投资教育活动,培养投资者理性投资的良好习惯,同时加强市场监管,完善市场交易制度,防止出现市场暴涨暴跌行情。     

正反馈交易与股票价格波动

在股票市场中,很多交易者不是对特定的消息作出反应,而是对过去的价格变动作出反应。如果交易者的交易策略是在股价出现上涨后买入,或在股价下跌后抛出,即"追涨杀跌",这类交易者称为正反馈交易者,其交易行为称为正反馈交易行为。本文建立了一个正反馈交易模型,分析了正反馈交易与股票价格的相关关系,最后对我国股市中的正反馈行为进行了检验,结果证明我国股市中确实存在正反馈交易行为。     

正反馈交易与股票价格波动

在股票市场中,很多交易者不是对特定的消息作出反应,而是对过去的价格变动作出反应。如果交易者的交易策略是在股价出现上涨后买入,或在股价下跌后抛出,即"追涨杀跌",这类交易者称为正反馈交易者,其交易行为称为正反馈交易行为。本文建立了一个正反馈交易模型,分析了正反馈交易与股票价格的相关关系,最后对我国股市中的正反馈行为进行了检验,结果证明我国股市中确实存在正反馈交易行为。     

Individual and institutional herding and the impact on stock returns: Evidence from Taiwan stock market

Using high frequency intraday data, this paper investigates the herding behavior of institutional and individual investors in the Taiwan stock market. The study finds evidence of herding by both investors but a stronger herding tendency among institutional than among individual investors. Institutional investors herd more on firms with small capitalizations and lower turnovers and they follow positive feedback strategies. The portfolios that institutional investors herd buy outperform those they sell by an average of 1.009% during the 20 days after intense trading episodes. By contrast, individual investors herd more on firms with small sizes and higher turnovers, and they crowd to buy (sell) stocks with negative (positive) past returns. The portfolios that individual investors herd buy underperform those they sell by an average of − 0.829% during the following 20 days. Moreover, these return differences of both investors are more pronounced under a market with higher pressure and among small stocks. These findings suggest that the herding of institutional investors speeds up the price-adjustment process and is more likely to be driven by correlated private information, while individual herding is most likely to be driven by behavior and emotions.     

信息不确定、坏消息与投资者交易行为

本文以2000年至2010年的A股上市公司违法违规事件为样本,分析该类事件中信息不确定性的影响,以及市场反应中的投资者交易行为。研究发现:上市公司市场价值在事件日呈显著下跌;然而,与直觉有些相悖的是,信息不确定程度与超额累积收益呈显著正相关,这意味着在坏消息到来时,不确定性反而提高了股票的市场价值;最后,通过对各类投资者在此类事件中的净买入情况分析,我们发现不同投资者的交易行为有明显差异。机构投资者在坏消息中采用了反向交易策略,并且知情交易促进机构投资者的买入。     

Asymmetric investor behavior between buyside and sellside: Evidence from investor classes in the Sri Lankan stock market

Using unique trading data for investor classes from Sri Lanka, this study finds asymmetric investor behavior between buyside and sellside in large trades. Investors are positive feedback traders on the buyside and contrarians on the sellside. Domestic investors exhibit more feedback and contrarian behavior than foreign investors, suggesting that foreign investors are more informed on the buyside and less informed on the sellside. Individuals are more feedback and contrarian traders than institutions. Foreign institutional investor sales do not precede, coincide with, or lead to significant returns. Trades do not lead to price momentum or reversals, but leave a permanent positive price effect.     

Institutional Traders' Behavior in an Emerging Stock Market: Empirical Evidence on Polish Pension Fund Investors

Abstract:   In this paper, we contribute to the literature on institutional herding and feedback trading by analysing the investment behavior of pension funds on the Polish stock market. Pension funds entered into the stock market due to the national pension system reform in 1999, providing a unique opportunity to receive deeper insight into the behavior of institutional investors in an emerging capital market. Our results show that Polish pension fund investors are to a greater extent involved in herd‐like behavior and pursue feedback trading strategies more often than their counterparts in mature markets. This finding is primarily attributed to a stringent investment regulation and high market concentration. We do not detect, however, that trading by the pension funds exerts significant influence on the future stock prices.     

Investor type trading behavior and trade performance: Evidence from the Thai stock market

This paper examines the trading behavior and decomposes the trading performance of foreign, individual and institutional investors as well as proprietary traders in a dynamic emerging stock market, the Stock Exchange of Thailand. Foreign investors follow a positive feedback, momentum strategy and are good short term market timers but have poor security selection performance in poor markets, thus suggesting that they have a macro (market timing) but not a micro (security selection) informational advantage relative to local investors. Institutions and proprietary traders have poor security selection trading performance. Individuals display herding behavior and have fairly good security selection performance, but individual investors appear to compensate proprietary traders for the provision of short term liquidity by proprietary traders, so individuals' security selection gains are canceled out by market timing losses.     

Investor type trading behavior and trade performance: Evidence from the Thai stock market

This paper examines the trading behavior and decomposes the trading performance of foreign, individual and institutional investors as well as proprietary traders in a dynamic emerging stock market, the Stock Exchange of Thailand. Foreign investors follow a positive feedback, momentum strategy and are good short term market timers but have poor security selection performance in poor markets, thus suggesting that they have a macro (market timing) but not a micro (security selection) informational advantage relative to local investors. Institutions and proprietary traders have poor security selection trading performance. Individuals display herding behavior and have fairly good security selection performance, but individual investors appear to compensate proprietary traders for the provision of short term liquidity by proprietary traders, so individuals' security selection gains are canceled out by market timing losses.     

Do Qualified Foreign Institutional Investors Herd in Taiwan's Securities Market?

This paper investigates whether and why qualified foreign institutional investors (QFIIs) in Taiwan herd when picking stocks. The evidence shows that QFIIs herd in Taiwan's securities market: They follow each other into and out of the same securities. We identify how the herding behavior forms and how it changes over time. The results suggest that there is an industry effect when QFIIs pick up stocks. They herd on securities classified in specific industries and also prefer stocks with high past returns as well as large firm size, supporting the argument that QFIIs are momentum traders. Characteristic herding and investigative herding explain QFIIs' trading behavior in Taiwan.     

Heterogeneous institutional investors and CEO compensation

This paper examines the relationship between institutional ownership and executive compensation by taking into account the heterogeneity of institutional investors. The paper finds that ownership by transient institutional investors, who have short investment horizons and active trading, is positively related to the performance sensitivity of option grants for CEOs. However, no significant relationship holds for other types of institutions, including those dedicated institutional investors, who have longer horizon and concentrated holdings. Further tests suggest that the positive relationship between transient institutional ownership and the CEO pay-for-performance sensitivity is not driven by the trading behavior of transient institutional investors when stock performance is good. Instead, the paper documents preference of transient institutional investors for greater performance sensitivity of option grants for CEOs. After using an instrument approach to control for preference and endogeneity, transient institutional ownership is no longer significantly related to the CEO pay-for-performance sensitivity. Additionally, the paper does not find dedicated institutional investors serve a monitoring role in correcting overcompensation paid to CEOs. After controlling for preference and endogeneity, neither the level of salary nor the level of total direct compensation for CEOs is significantly related to dedicated institutional ownership. The findings suggest that on average the influence of institutional investors on CEO compensation occurs indirectly through their preference in line with their different investment types.     

INSTITUTIONAL TRADING AND OPENING PRICE BEHAVIOR: EVIDENCE FROM A FAST‐EMERGING MARKET

Using daily and intraday data, we investigate the cross‐sectional relation between stock prices and institutional trading in the Taiwan stock market. Consistent with the investigative herding hypothesis, we find that institutional herding exists because of institutional positive feedback trading behavior rather than following trades made by other institutions, as suggested by the information cascade hypothesis. Moreover, the positive correlation between institutional trade imbalance and stock returns mainly comes from institutional positive feedback trading. The institutional trading decisions rely on returns measured not only over the lagged trading day but also over the opening session during the same day.