基于非参数日内跳跃检验和高频数据的公司信息披露对股市价格波动影响研究

本文以2012年1月4日至2013年12月31日之间的共481个交易日作为样本期间,以样本期间上交所发布的“上证180”成分股中的上市公司的经营公告、财务报告及证券分析师根据上述信息披露的股评三种信息为主要研究对象,从验证方法选择、高频数据选取、信息考察窗口优化及基于面板数据多元Logistics回归模型构建等四个方面将跳跃与不同信息相联系,分析股价波动与不同信息披露的关系。研究结果表明,当信息范围为公司特定的经营公告、财务报告及分析师建议时,经营公告是最具影响力的信息披露渠道,而分析师建议并不是引起股价异常波动最重要的信息。同时,本文研究揭示仅有20%的跳跃与此类信息披露相关,当解释变量覆盖代表宏观信息“系统性事件”和行业、板块信息的“行业事件”时,也仅40%的价格跳跃发生和信息披露有关。本文的研究不仅表明哪一种信息可能更具有投资价值,而且揭示在此研究基础上继续探究引起股价异常波动的其他起因事件可能更具有重要意义。     

Stock Market Reaction to Green Vehicle Innovation

We study the stock market reaction to announcements of global green vehicle innovation over a 14‐year time span (1996–2009) using the event study methodology. We document that the stock market generally reacts positively to automakers' announcements of environmental innovations, consistent with prior research on the wealth effects of innovation announcements. Our results indicate that crucial green product development decisions such as innovation type and market segment choices exert direct influence on a firm's market value. These results hold after controlling for firm size, leverage, profitability, R&D intensity, and oil price changes.     

从委托理财收益率看上市公司委托代理问题

本文将委托理财收益率作为研究对象,考察了上市公司的委托代理问题.通过研究发现,"可操控现金"与委托理财收益率显著负相关;若给定"可操控现金",大股东持股比例越高的公司其委托理财收益率越高.这一结果说明,"可操控现金"越多,上市公司的委托代理问题越严重;大股东的持股比例越高,其对管理层代理问题的约束力越强.研究还发现国外同类研究常用的"自由现金流"变量不能捕捉这一现象.     

中国股市账面市值比效应成因分析:基于行为金融视角

本文将账面市值比分解为反映公司基本面的有形收益和反映投资者主观预期的无形收益,以1994-2008年间在沪深两市交易的A股公司为研究样本,实证考察投资者对账面市值比中不同元素的反应,结果显示,投资者对公司发展前景的主观预期过分乐观或者悲观引发市场过度反应,随着市场回归理性,股票收益发生反转导致账面市值比效应。     

Product Design Awards and The Market Value of The Firm

Product design has increasingly been recognized as an important source of competitive advantage. This study empirically estimates the impact of effective design on the market value of the firm. We use a firm's receipt of a product design award as a proxy for its design effectiveness. Based on data from 264 announcements of design awards given to commercialized products between 1998 and 2011, we find that award announcements are associated with statistically significant positive stock market reactions. Depending on the benchmark model used to estimate the stock market reaction, the market reaction over a two‐day period (the day of announcement and the preceding day) ranges from 0.95% to 1.02%. The market reaction is more positive for smaller firms and for firms whose award winning products are consumer goods. However, a firm's growth potential, industry competitiveness, and whether a firm is a first time or repeated award winner do not significantly affect the market reaction.     

Shareholder Value Effects of Voluntary Emissions Reduction

The relationship between emissions reduction and firm financial performance has been studied with mixed results. We consider potential sources of this ambiguity by examining announcements of voluntary emissions reduction (VER) from 1990 to 2009. We measure the stock market reaction associated with VER announcements to estimate the effects of time, emissions type, and whether the reduction was announced ex ante or ex post. We find that the market reaction to VER significantly decreased over time. The changing nature of the market reaction to VER over time highlights the importance of evaluating the financial impact of any VER in the current context rather than relying on past findings. We also find that the market reaction is more positive if the reduction is for greenhouse gas (GHG) rather than other emissions types. In light of the increasing concern with GHGs, this finding should be welcome news for managers. Last, we find a more positive market reaction for VER announcements that are pledges or statements of intent rather than realized achievements of VER. Managers contemplating VER might find benefit (and at least no harm) in announcing their intent to reduce emissions rather than waiting until they have achieved the reduction.     

上市公司传闻的澄清效果研究——来自中国证券市场的证据

发布澄清公告是上市公司应对市场传闻的重要途径.然而,证券市场中澄清公告的实际效果如何,以及哪些因素会影响澄清效果尚未得到实证检验.为此,收集了从2000年到2008年中国A股市场1 960个澄清公告,从中整理出179个针对负面传闻进行"澄清"的样本.研究发现,澄清公告效果一定程度上依赖于公司的澄清方式,模糊澄清非但达不到效果,而且进一步加剧了传闻的影响,产生"澄清公告澄不清"的现象.多元回归模型的结果显示,澄清效果不仅与澄清方式有显著关系,而且还受到公司声誉、停牌等因素的影响.研究结论为传闻心理学实验研究的发现提供了中国证券市场的直接证据,同时也为上市公司有效应对传闻提供了新思路.     

Value creation through spin-offs: A review of the empirical evidence

This paper reviews the literature on the factors that influence the wealth effects associated with the announcements of corporate spin-offs (also known as demergers). Meta-analysis is used to summarize the findings of 26 event studies on spin-off announcements. A significantly positive average abnormal return of 3.02% is found during the event window. Returns are higher for larger spin-offs, for divestments that are tax or regulatory friendly and for spin-offs that lead to an improvement of industrial focus. It is also found that spin-offs that are later completed are associated with lower abnormal returns than non-completed spin-offs. The second part of the paper overviews studies on the long-run stock price performance of spin-offs. Even though early studies find a long-run superior performance, this effect is no longer found in later studies that use more refined statistical tests.     

锚定比率可以衡量股价高估吗？——基于崩盘风险视角的经验证据

股价高估指的是公司市场价值超出其内在价值的现象,但如何衡量内在价值一直存在争议。借鉴行为金融文献中锚定效应的概念,结合中国资本市场的特殊性,本文提出了锚定比率(简称"RPR")这一新的股价高估指标。为了证实该指标的有效性,本文利用事后的股价崩盘风险进行了相关检验。结果表明:第一,锚定比率与股价崩盘风险正相关;第二,更少的分析师跟踪、更多的散户持股以及更高的股票流动性均会强化锚定比率对股价崩盘风险的影响;第三,在控制常用的股价高估指标、两类代理问题和管理层"捂盘"行为后,本文的结果依然成立;第四,利用崩盘事件,本文证实了锚定比率会加剧股价下跌的程度,且长期来看股价会保持"惯性"而非"反转"。本文的研究表明投资者做决策时对股价高点存在明显的锚定效应,丰富了锚定效应在中国资本市场中的运用。更重要的是,本文提出了一个可能更适合于中国资本市场的股价高估指标,该指标意味着资本市场定价机制的不完善是导致股价高估和频繁崩盘的重要原因,这对于改善资本市场定价效率、降低股价崩盘风险有一定的启示作用。     

The interaction between stock prices and corporate investment: is Europe different?

I find limited evidence of firm learning from stock prices in Europe and uncover multifaceted complementarities between firm informational and operating environments in determining investment sensitivity to stock prices. Specifically, European firms seemingly do not shift away from their own (peer) stock prices even in instances in which their peers’ (own) stock prices become relatively more informative about firms’ fundamentals. This is consistent with European managers adopting more conservative strategies relative to their U.S.-based peers, and stock prices being less revealing in Europe than in the U.S. Furthermore, while a firm may attach equal weight to both its own stock prices and peer price innovations when peer firms are relatively smaller, investment responds more positively to peers’ price shocks than to that firm’s own stock prices when peers are relatively larger. Interestingly, investment sensitivity to peers’ stock prices decreases in peers’ market share, operating performance, and capital intensity. The decrease is accentuated when peer firms have more informative stock prices and are industry leaders or more capital intensive, thereby signaling perceived reduced growth opportunities. Broadly, these results imply that the specifics of the interaction between stock prices and firm behavior in the U.S. do not necessarily generalize to Europe. More important, these different learning patterns are partly attributable to differences in the amount of internal information, which in turn depends on country-level institutional infrastructures.     

股票流动性、股价信息含量与企业投资决策

市场微观结构和公司财务学的交叉研究是当前的研究热点,以2001年～2007年仅发行A股的非金融类上市公司平衡面板数据为样本,采用高频数据构造相对有效价差和相对报价价差衡量股票流动性,考察股票流动性、股价信息含量与公司投资决策之间的关系。研究结果表明,股票流动性与股价信息含量呈倒U型关系,但是股票信息含量的大小并没有影响到投资和股价之间的敏感性,说明市场上的投资者可能更多的是挖掘管理者已有但没有披露出来的私有信息,而不是管理者没有的私有信息,因而管理者并不需要据此进行投资决策。此外,股票流动性与企业投资水平正相关,意味着股票流动性通过扩展企业的投资机会集而影响企业的投资行为。使用不同的代理变量进行稳健性检验均没有改变研究结论。     

Kapitalmarktreaktionen auf Personalabbauprogramme: Welchen Einfluss haben Motiv,Umfang und Freiwilligkeit?

This study examines the effects of layoff announcements on the market value of German listed companies. Analyzing 136 announcements being published between 2000 and 2009, the results show marginal abnormal returns but high variance indicating that the market reaction might depend on specific characteristics. As potential determinants we particularly discuss the reasons for layoff, the size of layoff and the voluntariness of layoff. We find that reactive reasons like plant closures have a negative impact on shareholder value whilst active reasons like cost improvements enhance shareholder value. The size of layoff tends to induce negative effects. A voluntary layoff announcement however increases the value of a firm. Furthermore, we find a positive relationship between abnormal returns and human capital intensity and a negative one with both the manufacturing industry membership and financial leverage. In addition, the regression model extends prior literature since its coefficient of determination exceeds those in Anglo-American studies.     

高科技上市公司盈利能力影响因素的定量分析

利用Box-Cox变换和回归分析方法,对高科技上市公司的成长流量,行业增长比率,市场份额变化系数等定量指标与公司未来每股收益的相关性进行了定量化分析,并在此基础上提出了衡量高科技公司盈利能力的评价指标———边际成长流量比。实证研究结果表明:边际成长流量比可以科学地反映高科技上市公司在现行股票市价条件下的投资价值,是一种理想的评价指标。     

中国股票投资者的处置效应检验和参考价格选择

处置效应是一种比较典型的投资者非理性行为。本文在线性量价回归模型的基础上,引入Grinblatt和Han^[1]提出的资本利得突出量来检验中国股票投资者整体上是否存在处置效应。然后,使用新提出的6个参考价格与以往对股票市场研究中主要使用的两个参考价格(股票过去260周内加权平均价和过去52周内最高价)相比较,寻找更加适合处置效应研究的参考价格;同时,在选择不同的参考价格下,进一步检验投资者是否存在处置效应。研究结果表明:中国股票投资者整体上存在处置效应;并且在处置效应的研究中,新提出的参考价格——股票5周加权移动平均价明显优于以往学者提出的参考价格。因此,研究整个股票市场中投资者的处置效应时,使用该价格作为参考价格更加合理。     

基金管理人行为对股票市场的作用机制研究

基金管理人作为股票市场上的主要投资者,其投资心理和行为将会对股票市场产生深刻的影响.本文建立数学模型研究基金管理人过去的成败经历对其现在的投资心理和行为的影响以及这种投资心理和行为对股票市场交易量、价格波动性和基金管理人自身投资业绩的影响机制.研究结果表明,基金管理人过去经常失败的经历将使其变得过度悲观,过去经常成功的经历将使其变得过度自信;股票市场的均衡预期股票交易量和均衡价格波动性总是与基金管理人过去的成功经历正相关;过去过分成功或过分失败的基金管理人都不会在未来取得最好的实际预期业绩.     

基于最优估计理论的上市公司永久性盈余估计

估计上市公司的永久性盈余对进行股票投资是非常重要的.本文应用最优估计理论中的卡尔曼滤波和强跟踪滤波方法对上市公司的永久性盈余进行动态估计.实证结果表明基于强跟踪滤波的估计比基于卡尔曼滤波的估计精确许多.     

基于注意力传染机制的股市动量与反转模型研究

针对我国股市参与程度低,投资者非理性以及股价暴涨暴跌的基本事实,本文在一个简单的定价模型中刻画了新投资者参与市场背后的注意力传染机制,发现投资者关注在资产价格形成过程中扮演双重角色:一方面投资者的有限关注导致价格对信息反应不足,引起收益动量;另一方面,关注投资者通过注意力传染机制诱导无经验的正反馈交易者进入市场,导致收益反转。因此,注意力传染机制的引入合理地解释了股票动量效应与反转效应并存的事实,对于理解在成熟市场与新兴市场中投资者关注定价效应的差异具有重要意义。     

VaR方法及其在股市风险分析中的应用初探

本文讨论了度量投资风险的VaR方法的概念和计算方法,在股票价格随机游动的假设下计算了深圳股市在不同置信水平下的风险值,并与实际投资收益做了对比。在算例分析的基础上,对VaR方法在我国股票投资中的应用进行了初步探讨。     

系统风险冲击、企业创新能力与股票价格波动性:理论与实证

系统风险冲击和企业创新能力通过影响企业经营基本面和投资者行为而对股票价格波动性产生影响。本文首先建立数学模型从理论上研究系统风险冲击和企业创新能力对股票价格波动性的影响机理;然后以中国A股上市公司2013-2017年期间的相关数据为样本,以2013-2017年期间中国沪深300指数跌幅超过18%的持续性下跌为系统风险冲击源,从创新投入、创新产出和创新环境三个维度构建创新能力指标,采用层次回归分析方法对理论模型结果进行实证检验。研究发现,股票价格波动性与系统风险冲击正相关,与企业创新能力负相关,企业创新能力能够弱化系统风险冲击对股票价格波动性的影响,进而增强股票市场稳定性。规范市场监管行为、改革上市和退市制度、优化创新激励机制、完善上市公司信息披露制度是降低系统风险冲击影响、保障股票市场稳定发展的重要途径。     

企业创新策略选择与股价波动之间关系实证研究

本文以内地上市公司为研究对象,运用事件分析法研究了不同公司采用不同创新策略时,股票市场对其预期收益将做出何种调整与变化.研究姥.果表明:托宾Q值大于1的企业采取外部创新以及托宾Q值小于1的企业采取内部创新时,股价将上升;托宾Q值大于1的企业采取内部创新以及托宾Q值小于1的企业采取外部创新时,股价将下跌.