我国股市波动的信息不确定性与投资者行为效应研究

维护我国股票市场的功能与稳定,需要更多地考虑来自信息不确定性及投资者行为对股价波动的影响。应有计划、有步骤地适度扩容,进一步培育和发展我国股市的机构投资主体;货币政策应建立前瞻性的通货膨胀目标规则,并充分利用股价所包含的各类政策信息;应强化信息披露机制,建立上市公司强制分红制度,加强对投资者的信息交流与教育引导。     

机构投资者实地调研能否缓解股价同步性——基于我国A股上市公司的经验证据

本文以2014-2018年我国深圳A股上市公司为样本,实证检验了机构投资者实地调研与股价同步性的关系,并探究了信息披露质量和机构投资者持股比例对此关系的调节作用.研究结果表明,机构投资者实地调研提升了公司的特质信息含量,显著降低了股价同步性.进一步研究发现,机构投资者实地调研对股价同步性的降低作用在信息披露质量较好的公司和机构持股比例较大的公司更为显著.本文的研究不仅拓展了现有关于机构投资者信息中介作用的研究,丰富了关于股价同步性影响因素方面的相关文献,并为监管部门完善上市公司信息披露制度、引导投资者与上市公司深入交流,提供了有益启示.     

机构投资者持股与股票收益率波动研究

近几年来,借鉴西方成熟市场的发展经验,我国开始大力发展以投资基金为代表的机构投资者,希望发挥机构投资者的专业能力和信息优势稳定股票市场、降低投资风险。但机构投资者在我国资本市场是否真正起到了应有的作用仍是一个有待商榷的问题。本文以1999年至2007年沪深两市上市公司数据构建面板数据,研究了机构投资者持股比例对股票收益率波动的影响,实证结果证明机构投资者持股比例与股票收益率波动负相关,机构投资者对我国股票市场起到了一定的稳定作用。     

ESG评级、机构投资者持股比例与股价崩盘风险

本文使用2012-2021年沪深A股上市公司的数据,研究分析上市公司ESG信息披露对股价崩盘风险的影响。研究结果表明:(1)上市公司ESG信息披露水平与股票市场价格崩盘风险呈显著的负相关。(2)机制检验表明,上市公司ESG信息披露能够促进机构投资者增加持股比例,作为资本市场的信息中介,机构投资者将会释放更多积极的股价信息,对资本市场产生积极效应,并促进投资者进行合理的投资决策,进而降低股价崩盘风险。(3)异质性分析发现,对于非国有企业、非重污染企业、大规模上市公司,其ESG信息披露抑制股价崩盘风险的作用更强。     

我国证券市场股价波动同步性研究

本文从介绍股价波动同步性入手,指出目前我国证券市场股价波动同步性的现状。分析出我国证券市场上股价波动同步性的影响因素,包括投资者行为、制度环境以及公司信息环境等。最后,在深入分析现状及影响因素的基础上,本文提出了加强机构投资者自身治理、提高上市公司的信息透明度等相关政策建议来改善目前我国股价波动同步性的现象。     

浅析影响我国股票市场的因素

中国股市经过22年建设,股票市值和上市公司家数均得到了迅猛发展。可我国股市波动较大,经历过几次大的牛市和熊市,虽然给部分投资者带来了丰厚的盈利,但更多的是带来巨大的亏损,特别是对于中小投资者。所以研究我国股票市场的影响因素非常重要,本文从宏观经济,股市供求等几个方面阐述了影响我国股票市场的因素。     

浅析影响我国股票市场的因素

中国股市经过22年建设,股票市值和上市公司家数均得到了迅猛发展。可我国股市波动较大,经历过几次大的牛市和熊市,虽然给部分投资者带来了丰厚的盈利,但更多的是带来巨大的亏损,特别是对于中小投资者。所以研究我国股票市场的影响因素非常重要,本文从宏观经济,股市供求等几个方面阐述了影响我国股票市场的因素。     

宏观经济条件下投资者情绪对股票市场波动影响研究——基于主板市场和中小板市场的实证分析

股票市场波动与投资者情绪和宏观经济存在着密切联系,宏观经济又会影响投资者情绪。本文以2014~2018年为研究时间段,采用主成分分析法和多元回归法构建投资者情绪综合指标,使用SVAR模型研究了宏观经济条件在投资者情绪对股票市场波动的冲击过程中起到的影响,并比较了该影响在主板市场和中小板市场之间的不同。结果显示:宏观经济条件会放大投资者情绪对股票市场波动的冲击幅度并延长冲击时间;主板市场规模更大,宏观经济条件对情绪冲击的放大幅度更大;中小板市场活跃度和投资者关注度较低,对投资者情绪冲击的反应会被减慢。     

大股东交易与中国A股市场股价暴涨暴跌风险北大核心

本文以2008-2016年A股上市公司为样本,研究大股东增持或减持股票如何影响股价极端波动现象的发生。结果表明:大股东交易强度提升显著增加了股价暴涨暴跌风险,其影响主要来源于大股东减持而非大股东增持;上市公司的信息透明度越低、管理层持股比例越高、管理层权力越小,则大股东交易对股价极端波动风险的影响越显著;较高比例的机构投资者持股和独立董事设置能够有效加强对上市公司的监督,削弱大股东交易对股价极端波动风险的不利影响。为了进一步规范大股东交易行为、维护股票市场稳定运行,提出以下对策建议:第一,完善规制大股东交易行为的法律法规和监管规则,防范内幕交易,避免大股东集中、大幅、无序减持股票对市场稳定带来冲击;第二,强化上市公司信息披露要求,提高信息透明度;第三,推动上市公司吸引机构投资者持股、提高独立董事比例,优化公司内部制衡和外部监督机制,以实现对大股东行为的有效制衡和约束。     

机构投资者持股与流动性成本——来自中国上市公司的经验证据

现有的研究认为,机构投资者通过两个渠道影响流动性成本:逆向选择和信息效率。一方面,因信息不对称而带来的逆向选择问题会增大流动性成本;另一方面,机构投资者通过股票交易使私有信息渗透到股价之中,则会提高信息效率,减少流动性成本。因此,机构投资者与流动性成本之间的关系成为一个实证问题。本文研究发现,我国机构投资者持股增加了报价价差、有效价差和PIN值;进一步地,证券投资基金持股比其他机构投资者持股更可能导致流动性成本的增加。因此,我们认为,监管层应严厉打击机构投资者获取内幕信息,加强上市公司信息披露监管,减少逆向选择问题,同时应减少机构投资者操纵股票市场等影响股价信息效率的行为。     

Economic policy uncertainty,investor attention and post-earnings announcement drift

How the market incorporates information into stock price is a core issue in finance. This study focuses on the impact of economic policy uncertainty (EPU) on the stock prices information efficiency of China's A-share market and underlying role of investors' attention allocation mechanism. This study analyzes the information efficiency of stock prices using the sensitivity of stock cumulative abnormal return to earnings information across different windows following earnings announcement. Based on the earnings announcement events of listed companies in China's A-share market, this study presents an empirical study of the aforementioned issues using event study and regression analysis methods. The following results are seen: (1) EPU aggravates the underreaction of stock price earnings information and the post-earnings announcement drift in the A-share market. (2) Under highly uncertain economic policies, investors show a limited attention allocation pattern of devoting increasing attention to macroeconomic policies and decreasing attention to earnings information, which leads to a decrease in the information efficiency of stock price. This study also analyzes the heterogeneity of the influence of EPU on stock price information efficiency using the institutional shareholding ratio. The results show that increasing institutional shareholding does not reduce the adverse effects of EPU on the information efficiency of stock prices. This study not only provides empirical evidence for Brunnermeier, Sockin, and Xiong (2022) and rational inattention theory, but also reveals that institutional investors show similar behavioral characteristics to retail investors in China's stock market. The results of this study have policy significance for improving the information efficiency of stock market.     

Exploring the relationship between investor sentiment and price volatility

By performing Grey relation analysis, this study elucidates the relationship between investor sentiment and price volatility in the Taiwanese stock market. A sequential relationship is identified between investor sentiment and price volatility, and ranked according to order of importance. Analytical results show that short sales volumes may be an individual leading indicator useful in observing the effects of sentiment on price volatility, followed by open interest put/call ratios and trading volumes, and buy/sell orders. Institutional investors are related, to a lesser extent, to price volatility and sentiment. Qualified foreign institutional investors, or more rational investors, are the least influenced by price volatility, followed by securities investment trust companies and dealers. TAIEX options exert the strongest influence on sentiment during the study period, making them a valuable reference for gauging price volatility.     

机构持股对股价微观波动影响的非对称性

文章利用topview机构投资者日持股数据,构建股价波动率与机构投资者日净买率等指标,使用GMM回归、滚动回归、递归回归,从个股角度动态分析机构投资者对股价微观波动的影响。实证结果表明,机构投资者对股价微观波动的影响因不同的市场状态而具有非对称性,并可以用信息假说进行解释。管理层应依据不同的市场状态而采取合适的措施以实现机构投资者的稳定作用。     

Institutional investor horizon and stock price synchronicity: Do product market competition and analyst coverage matter?

This paper provides new insights into the relation between institutional investment horizon and stock price synchronicity and investigates whether this relationship depends on the intensity of product market competition and analyst coverage. Based on a sample of French listed companies, we find that long-term (short-term) institutional investors are associated with lower (higher) stock price synchronicity. The results also show that the negative effect of long-term institutional investors is more accentuated for firms in less competitive markets and with high analyst coverage. An additional analysis shows that the synchronicity reduction effect does not vary during the financial crisis. Overall, these findings suggest that unlike their short-term counterparts, long term investors reduce asymmetric information and help disseminate firm-specific information into stock prices.     

Forecasting stock volatility with economic policy uncertainty: A smooth transition GARCH-MIDAS model

Given that policy uncertainty shocks in the economic environment can exacerbate financial market volatility and pose financial risks, this paper utilizes a smooth transition version of the GARCH-MIDAS model to investigate the impact of different structural state changes in economic policy uncertainty (EPU) on stock market volatility. The extended model explains the nonlinear effects of the macro variables and the structural break changes in regime transitions. The empirical results confirm that the EPU indicators provide effective prediction information for stock volatility from the in-sample and out-of-sample analyses, which reveals that the smooth transition model provides an effective method for detecting the possible regime changes between stock volatility and macroeconomic uncertainty. Additionally, we further confirm that some category-specific EPU indicators also have strong smooth transition behaviour with respect to stock volatility. More important, our new model provides significant economic value to investors from a utility gain perspective. Overall, the institutional changes present in EPU play a nonnegligible and important role in stock market volatility. Accurate identification of the structural features of financial data helps investors deepen their understanding of the sources of stock market volatility.     

Daily institutional trades and stock price volatility in a retail investor dominated emerging market

We examine the short-run dynamic relation between daily institutional trading and stock price volatility in a retail investor-dominated emerging market. We find a significantly negative relation between volatility and institutional net trading that is mainly due to the unexpected institutional trading. The price volatility–institutional trade relation differs for institutional buys and institutional sells, and for small and large stocks. Institutional investors herd-trade in large stocks, but do not systematically engage in positive-feedback trading. We argue that the net impact of informational and noninformational institutional trades determines the relation between volatility and institutional trading, and that the relation is negative when informational trading by institutions prevails.     

Stock market volatility and equity returns: Evidence from a two-state Markov-switching model with regressors

This paper proposes a two-state Markov-switching model for stock market returns in which the state-dependent expected returns, their variance and associated regime-switching dynamics are allowed to respond to market information. More specifically, we apply this model to examine the explanatory and predictive power of price range and trading volume for return volatility. Our findings indicate that a negative relation between equity market returns and volatility prevails even after having controlled for the time-varying determinants of conditional volatility within each regime. We also find an asymmetry in the effect of price range on intra- and inter-regime return volatility. While price range has a stronger effect in the high volatility state, it appears to significantly affect only the transition probabilities when the stock market is in the low volatility state but not in the high volatility state. Finally, we provide evidence consistent with the ‘rebound’ model of asset returns proposed by Samuelson (1991), suggesting that long-horizon investors are expected to invest more in risky assets than short-horizon investors.     

个人大股东持股与股价暴跌风险

本文以2007至2016年中国A股上市公司为样本,考察了个人大股东持股与股价暴跌风险之间的关系。研究发现:第一,个人大股东持股比例的增加能够显著降低公司未来股价暴跌风险。这一结论在剔除了个人大股东中董监高持股数量、进行内生性处理、更换不同统计检验方法后依然成立。第二,个人大股东持股对公司管理层监督的效果并不明显,个人大股东持股比例的增加对于公司应计盈余管理、真实盈余管理、投资效率、过度投资等可能影响公司股价暴跌风险的经营指标并没有显著影响。第三,个人大股东的持股加强了公司股权制衡的力度,进而显著降低了公司股价暴跌风险。股权制衡机制解释了大股东持股对股价暴跌风险一半以上的影响。本文的研究对于全面认识个人大股东在资本市场中发挥的作用,促进股市平稳发展具有重要的理论和现实意义。     

险资持股对上市公司股价波动的影响研究 ——基于机构投资者异质性视角

保险机构已经成为资本市场重要的机构投资者,其在整个资本市场中的作用日益受到关注.基于机构投资者异质性的视角,对保险机构和证券投资基金、社保基金以及Q FII等其他机构投资者的持股特征进行对比分析,总结梳理保险机构投资者持股的特征.并运用面板数据模型,从长期持股和持股比例变动两个方面对比分析保险机构持股与证券投资基金持股对股价波动的影响.结果表明:在样本期间内,相对于证券投资基金,保险机构长期持股起到了稳定股市的作用,但保险机构持股比例变动会加剧股市的波动.     

国际原油价格对我国新能源行业股票价格的波动溢出效应研究

在大气污染日益严峻的情况下,新能源行业受政府大力支持和投资者青睐。新能源与原油一定程度上互为替代品,理论上国际原油价格必然对我国新能源行业股票价格有显著的波动溢出效应,但有些学者却持反对态度,认为我国股票市场对外还没有完全开放,新能源行业发展又很不成熟,所以该溢出效应很难显著。文章运用VAR- Asymmetric- BEKK模型进行比较研究得出：在未去除我国整体股市行情因素时,国际原油价格波动对我国新能源行业股票价格波动溢出效应不显著;而在去除我国整体股行情因素时,国际原油价格波动对我国新能源行业股票价格波动溢出效应在1%显著性水平下显著。表明存在从国际原油价格向我国新能源行业股票价格的波动溢出效应,只是该溢出效应被我国股市总体行情掩盖了。