公司策略性媒体披露行为研究最新进展与述评

因为新闻媒体对资产定价的重要影响,致使越来越多公司管理层开始重视对媒体披露的主动管理,特别是重大事件期间,公司的策略性媒体披露倾向尤为明显,以谋求自身利益的最大化。与此同时,这一现象也日益为学者们所关注,并开始成为公司财务与金融研究的热点前沿。本文主要基于行为金融学视角,从公司策略性媒体披露的内涵、动因、方式、主要内容及表现等维度,对现有相关文献进行了系统梳理,旨在进一步剖析公司管理层在媒体披露中的重要作用,帮助人们更好地理解和把握股票市场波动的成因及本质。最后,就其未来研究方向做了进一步的探讨。     

企业社会责任能降低股价同步性吗？——基于强制披露企业社会责任报告的准自然实验

中国2008 年沪深证券交易所强制披露社会责任报告政策为笔者研究其政策效应提供了准 自然实验,文章以2006-2011 年中国A 股上市公司为样本,分别从信息不对称和代理成本两条路 径研究强制披露社会责任报告对股价同步性的影响。运用PSM-DID 双重差分模型研究发现: 强制 披露社会责任报告与股价同步性呈现显著负相关关系,说明强制披露社会责任报告有助于降低股 价同步性,在通过安慰剂实验、变量替换和平行效应检验等稳健性检验后,以上结论仍成立。对 影响路径的分析发现,强制披露社会责任报告通过降低信息不对称和代理成本影响未来股价同步 性。     

Time-varying relationship of news sentiment,implied volatility and stock returns

I examine the relationship between aggregate news sentiment, S&P 500 index (SPX) returns, and changes in the implied volatility index (VIX). I find a significant negative contemporaneous relationship between changes in VIX and both news sentiment and stock returns. This relationship is asymmetric whereby changes in VIX are larger following negative news and/or stock market declines. Vector autoregression (VAR) analysis of the dynamics and cross-dependencies between variables reveals a strong positive relationship between previous and current period changes in implied volatility and stock returns, while current period and lagged news sentiment has a significant positive (negative) relationship with stock returns (changes in VIX). I develop a simple trading strategy whereby high (low) levels of implied volatility signal attractive opportunities to take short (long) positions in the underlying index, while extremely negative (positive) news sentiment signals opportunities to enter short (long) index positions. The investor fear gauge (VIX) appears to perform better than news sentiment measures in forecasting future returns.     

Portfolio efficiency analysis with SFA: the case of PSI-20 companies

This study aimed to assess the technical efficiency (TE) of individual companies and their respective sectors that are traded on the Portuguese stock market. We accomplished this by combining the internal input variables (e.g., ‘market value and return’) with exogenous variables (e.g., ‘interest income’, ‘depreciation’, ‘cost of goods’, ‘employees’ and ‘net sales’) into a Stochastic Frontier Analysis (SFA) model. The TE of the PSI-20 (Portuguese Stock Index) was estimated using factors that affect efficiency variability. The main advantage of using the SFA approach is its potential to discriminate between measurement error and systematic inefficiencies in the estimation process. The results demonstrated that TE is higher for enterprises in the industrial, construction and distribution sectors, whereas the commercial banking sector has the lowest TE scores. The ‘employees’ and ‘depreciation’ are the variables which most contribute to stock market inefficiency.     

Economic integration and stock market dynamic linkages: evidence in the context of Australia and Asia

Countries are becoming economically integrated and it is contended that this will also lead to their financial markets becoming integrated. This contention is important since international financial market integration diminishes portfolio diversification benefits and creates contagion risk. We test this contention in this article in the context of the Australasian region. Australia and Asia have experienced very significant economic integration through a rapid growth in their bilateral trade. We utilize a battery of econometric techniques – cointegration, asymmetric generalized dynamic conditional correlations and panel regression models. As expected, we find that trade intensity significantly drives the interdependence between their stock markets in both the short run and the long run. Thus, given the ever increasing economic integration in this region, this finding implies that their stock markets face the risk of contagion, and that investors in these markets would also be confronted with the prospect of lower diversification benefits.     

A non-linear approach for predicting stock returns and volatility with the use of investor sentiment indices

The popular sentiment-based investor index S^BW introduced by Baker and Wurgler (2006, 2007) is shown to have no predictive ability for stock returns. However, Huang et al. (2015) developed a new investor sentiment index, S^PLS, which can predict monthly stock returns based on a linear framework. However, the linear model may lead to misspecification and lack of robustness. We provide statistical evidence that the relationship between stock returns, S^BW and S^PLS is characterized by structural instability and inherent nonlinearity. Given this, using a nonparametric causality approach, we show that neither S^BW nor S^PLS predicts stock market returns or even its volatility, as opposed to previous empirical evidence.     

P2P网络借贷市场对资本市场的风险溢出效应

构建Copula-GARCH模型,并利用2013—2016年中国P2P网络借贷市场、股票市场和债券市场的日收益率数据,实证研究了P2P网络借贷市场对资本市场的风险溢出效应。结果显示:P2P网络借贷市场与股票市场之间存在"跷跷板"效应,与债券市场之间呈现出较弱的联动效应;P2P网络借贷市场与股票市场和债券市场的上、下尾部相关性均很弱,风险溢出效应不显著。结论表明:在确保金融系统稳定的同时,中国可以适度发展P2P网络借贷行业。     

Reputational Herding in Financial Markets: A Laboratory Experiment

We study reputational herding in financial markets in a laboratory experiment. In the spirit of Dasgupta and Prat [2008], career concerns are introduced in a sequential asset market where wages for investors are set by subjects in the role of employers. Employers can observe investment behavior, but not investors' ability types. Thereby, reputational incentives may arise endogenously. We find that a sizable fraction of investors follows an established trend even in a setting where there are no reputational incentives. In a setting where there are reputational concerns, they do not seem to create substantial herd behavior.     

地方官员更替、企业辖区知名度与股价同步性

以2009～2013年我国A股上市公司为研究样本,实证分析地方官员更替、辖区企业知名度与股价同步性的关系,结果表明:地市级政府官员变更所带来的政治不确定性会显著降低辖区企业的股价同步性,并且相对于新任官员来源于本地而言,新任官员来源于异地更能够显著地降低辖区内企业的股价同步性.进一步研究还发现,当地市级政府官员发生变更时,相对于辖区知名度较高的企业而言,辖区知名度较低的企业会披露更多的企业私有信息以应对政治不确定性风险,从而其股价同步性有了更大程度的降低.研究的结论证实了政治不确定风险的增加能够显著降低辖区内企业的股价同步性,客观上有助于提高股价的信息含量.     

Investment bank monitoring and bonding of security analysts’ research

We assess investment banks’ influence over the agreement between their analysts’ research behavior and their clients’ interests, in the post-reform era. Competing banks discipline their analysts with worse career outcomes for producing biased reports, issuing shirking reports, and for involvement in the earnings guidance game, showing meaningful monitoring of their analysts. Highly reputable banks provide more monitoring discipline of their analysts and bonding of their moral hazard than other banks. The findings agree with the banks taking responsibility for aligning analysts’ behavior with clients’ interests.