公募基金改善了市场定价效率吗?——持股基金质量与股票收益

由于忽略了基金管理能力差异,现有文献无法证明公募基金可以改善市场定价效率,即基金持有的股票未来收益率并未优于市场平均水平。本文以2005—2020年中国市场数据为基础,构建了股票的持股基金质量指标(而非权重),并研究了该指标对未来表现的预测能力。实证结果表明,持股基金质量较高的股票表现显著优于质量较低的股票,基于该指标构建的套利组合可以获得年化14%左右的超额收益,且该现象不能被基金持股权重、羊群效应引起的价格压力、系统性风险和其他定价异象所解释。本文发现我国公募基金持仓正向预测资产未来收益率的证据,可为相关监管政策制定和执行提供启示。     

基金网络中机构投资者抱团对股票市场的影响研究

基于Louvain算法从机构投资者网络中提取机构投资者团体,建立以重仓股票为链接的基金网络模型,生成基金团体持股变量,研究机构投资者抱团对股票市场的影响.研究发现:机构投资者抱团行为加剧了公司股价的波动,机构投资者抱团持股比例越大,加剧作用越显著.同时,机构投资者抱团降低了股票的流动性,基金网络交流越密切,抱团持股比例越大,股票流动性成本越高,流动性越差.进一步研究发现,相比牛市,基金在熊市的抱团行为对股价波动的放大效应更明显;在流动性层面,相比牛市,熊市时的机构投资者抱团行为对股票流动性的削弱作用更为显著.     

机构投资者信息共享会引来黑天鹅吗?——基金信息网络与极端市场风险北大核心CSSCISSCI

极端风险的形成机理是学术界和业界共同关心的重要问题,本文通过构建以重仓股为链接的基金信息网络模型,研究了机构投资者之间的信息联系和传递对极端风险的影响机制。本文的结果表明:基金持股之间的信息网络密度不仅会增加股票总体和特质风险,而且会显著加大股票极端下跌和极端上涨的概率,其中对极端下跌市场的影响更大,也即基金之间的信息共享机制容易引发黑天鹅事件。此外还发现,当流动性成为极端市场风险的主要推手时,基金信息共享机制对极端市场的影响变得不再显著,因此基金信息共享机制与流动性二者之间对极端市场的形成存在着替代效应。本文的研究结果不仅有助于更好理解我国机构投资者的作用,对加强市场风险管理、丰富投资交易策略也有一定启示。     

基金经理更换、股票联动与股票价格

基金经理更换打破了基金共同持股投资组合中股票的关联性,降低了股票收益率相关性,进而影响了股票价格。本文基于基金共同持股和基金经理更换构建了对冲投资组合,获得0.1%的日超额收益率。基金投资组合中股票收益率相关性能够解释这种超额收益率,本文发现基金更换经理后,新基金经理重建投资组合,打破了原投资组合中股票间的关联,股票收益率相关性减弱,基金共同持股程度高的股票价格受到了更大影响。基金的被动流动性冲击不能解释本文的发现。本文的研究表明基金经理变更等基金管理行为通过股票收益率相关性对股票价格产生了重要影响。     

阳光私募是否改善了股价信息效率？

本文以沪深两市的股票为研究对象,考察了近几年逐渐成长起来的阳光私募基金对股票流动性和信息效率的影响。研究发现:阳光私募基金持股比例越高,股票流动性越强。说明阳光私募基金改善了股票的流动性,能起到灵活市场的作用。阳光私募基金持有股票比例越高,股票信息效率越高。阳光私募基金交易股票的频率越高,信息效率越低。说明阳光私募基金持有股票在一定程度上能够改善股票的信息效率,但频繁交易却降低了信息效率,这也从另一个角度说明阳光私募基金应采取较为稳健的投资策略。由上述结论可以推断出,阳光私募基金在一定程度上起到了稳定市场的作用。     

保险公司持股偏好的实证研究

保险公司的投资特征直接影响保险公司的业绩水平和保险行业的健康发展。在众多投资渠道中,持股偏好最能体现保险公司投资特征：数量众多的股票,在风险和流动性等方面存在显著差异。偏好何种类型股票,能够较为全面反映保险公司的投资行为特征。利用2006年～2011年上市公司股权结构数据对保险公司持股的偏好进行考察;研究结果发现,与非保险类的机构投资者不同,保险公司的股票投资表现出对于安全性和流动性的更强烈偏好。这种持股偏好与保险公司的资金来源性质和业务运营特点相匹配。当放宽投资范围约束时,保险公司对于流动性较高的股票和风险较低的公司有更加明显的投资偏好。     

我国社保基金持股偏好研究

社保基金在证券市场上的投资表现会直接影响其运行的稳定性,由于其资金来源的特殊性,社保基金对于选择投资对象有没有明显的偏好呢？本文利用2008—2018年我国A股上市公司的数据,研究社保基金的持股偏好。研究表明,社保基金在进行投资时对于经营业绩好、风险性低、股权集中度高、估值偏低的股票具有明显的偏好。进一步研究发现,与保险公司偏好股权集中度低的股票、公募基金偏好流动性高的股票相比,社保基金更偏好股权集中度高的股票,而对于流动性高的股票并没有明显的偏好。     

我国基金重仓股选股偏好的时期似无关回归分析

基于基金重仓股季度面板数据,本文采用时期似无关回归模型分析了四大类共28个指标对基金持股比例的影响,并利用基金重仓股的统计值特点发现基金筛选股票的标准。研究结果表明,基金确实在寻求价值型投资,扩大基金规模可减轻股市投机行为;基金在调研阶段和操盘阶段对风险有不同的偏好,调研阶段规避风险,操盘阶段偏好高风险高回报;基金偏爱长期流动性好的股票;开放式基金的选股要求高于封闭式基金,牛市时基金的选股要求高于熊市;基金偏爱关注率高、信息丰富的股票;基金对行业的偏好基于行业的业绩表现;基金重仓股持股比例基本上与指数有相似的变化趋势。     

员工薪酬竞争力与上市公司员工持股

基于员工持股相关理论,本文考察了员工薪酬竞争力对我国上市公司是否实施员工持股的可能影响。实证结果显示,员工薪酬竞争力越弱,企业越可能实施员工持股;且员工薪酬竞争力越弱,员工持股的锁定期限越长、覆盖人数越多以及员工股比例越高。进一步研究发现,员工薪酬竞争力与实施员工持股可能性的负相关关系,只在外部劳动力市场流动性高和内部人力资源成本较高以及融资约束较为严重的样本中显著。上述研究发现表明,上市公司的员工持股在一定程度上是企业在面临外部劳动力市场流动性压力和内部较高人力资源成本以及融资约束时,缓解员工薪酬竞争力不足的现实途径。本文的研究结论为完善上市公司员工持股制度提供了经验证据支持,同时拓展了员工持股、职工薪酬及收入分配等领域的相关研究文献。     

基金经理羊群效应与股票流动性——基于主动型基金的研究

不同于现有文献多集中于讨论羊群行为对股票价格和波动性的影响,本文构建一个包含基金经理和散户投资者的三期模型,探究基金经理羊群效应对股票流动性的影响机制。我们通过均衡求解发现,基金经理羊群行为降低了风险资产投资,股票流动性下降。本文还使用2005-2020年我国股票市场中主动型基金投资股票的数据实证检验,发现基金经理存在羊群行为,该行为导致股票流动性下降。     

Flight-to-liquidity,market uncertainty,and the actions of mutual fund investors

We explore the trading decisions of equity mutual funds during ten periods of extreme market uncertainty. We find that mutual funds reduced their aggregate holdings of illiquid stocks. Exploring the drivers behind this result reveals that this is mainly driven by larger withdrawals from funds that hold less liquid stocks. We further find that the sell-off of illiquid stocks occurred only after initial deterioration in market conditions, consistent with retail investors’ response to bad performance. At a broader level, this shows that mutual funds consumed liquidity during periods where liquidity was most valuable. Moreover, the fact that fund managers traded in response to these withdrawals suggests a potentially magnifying channel for the drop in illiquid stock prices, also known as flight-to-liquidity.     

Leverage constraints and asset prices: Insights from mutual fund risk taking

Prior theory suggests that time variation in the degree to which leverage constraints bind affects the pricing kernel. We propose a measure for this leverage constraint tightness by inverting the argument that constrained investors tilt their portfolios to riskier assets. We show that the average market beta of actively managed mutual funds—intermediaries facing leverage restrictions—captures their desire for leverage and thus the tightness of constraints. Consistent with theory, it strongly predicts returns of the betting-against-beta portfolio, and is a priced risk factor in the cross-section of mutual funds and stocks. Funds with low exposure to the factor outperform high-exposure funds by 5% annually, and for stocks this difference reaches 7%. Our results show that the tightness of leverage constraints has important implications for asset prices.     

Stock Market Declines and Liquidity

Consistent with recent theoretical models where binding capital constraints lead to sudden liquidity dry-ups, we find that negative market returns decrease stock liquidity, especially during times of tightness in the funding market. The asymmetric effect of changes in aggregate asset values on liquidity and commonality in liquidity cannot be fully explained by changes in demand for liquidity or volatility effects. We document interindustry spillover effects in liquidity, which are likely to arise from capital constraints in the market making sector. We also find economically significant returns to supplying liquidity following periods of large drops in market valuations.     

Small-cap equity mutual fund managers as liquidity providers

This paper examines the relation between the performance of small-cap equity mutual funds and the liquidity characteristics of their asset holdings. We study the trading behavior of fund managers and show that on average, they tend to buy less liquid stocks and sell more liquid stocks. We introduce the notion of net “liquidity creation” by fund managers and examine its role in explaining the cross section of small-cap equity mutual fund returns. Our empirical results show that on average, small-cap mutual fund managers are able to earn an additional 1.5% return per year as compensation for providing such liquidity services to the market.     

Mandatory Portfolio Disclosure,Stock Liquidity,and Mutual Fund Performance

We examine the impact of mandatory portfolio disclosure by mutual funds on stock liquidity and fund performance. We develop a model of informed trading with disclosure and test its predictions using the May 2004 SEC regulation requiring more frequent disclosure. Stocks with higher fund ownership, especially those held by more informed funds or subject to greater information asymmetry, experience larger increases in liquidity after the regulation change. More informed funds, especially those holding stocks with greater information asymmetry, experience greater performance deterioration after the regulation change. Overall, mandatory disclosure improves stock liquidity but imposes costs on informed investors.     

The liquidity risk of liquid hedge funds

This paper evaluates hedge funds that grant favorable redemption terms to investors. Within this group of purportedly liquid funds, high net inflow funds subsequently outperform low net inflow funds by 4.79% per year after adjusting for risk. The return impact of fund flows is stronger when funds embrace liquidity risk, when market liquidity is low, and when funding liquidity, as measured by the Treasury-Eurodollar spread, aggregate hedge fund flows, and prime broker stock returns, is tight. In keeping with an agency explanation, funds with strong incentives to raise capital, low manager option deltas, and no manager capital co-invested are more likely to take on excessive liquidity risk. These results resonate with the theory of funding liquidity by Brunnermeier and Pedersen (2009).     

Mutual Fund Stock‐Picking Skill: New Evidence from Valuation‐ versus Liquidity‐Motivated Trading

We propose a novel Trade Motivation Matrix that allows differentiating funds’ valuation‐motivated (VM) and liquidity‐motivated (LM) trades on single trade level. It thus enables analyses of stock‐picking skill on three levels: trade, stock, and fund. On trade level, we find significant outperformance of VM buys and significant underperformance of VM sells, indicating manager stock‐picking skills, especially during illiquid market periods. VM trades outperform LM trades, confirming negative performance effects due to flow risk, especially when market liquidity is low. On stock level, collective VM buying explains high future stock returns while collective VM selling is related to future losses, indicating wisdom of the crowd. On fund level, higher trading discretion, measured by a higher degree of VM trading, is observed for smaller, older funds holding higher cash buffers. Finally, higher trading discretion is related to higher future fund alpha, especially during illiquid times.     

Liquidity Dry-ups in equity markets

This paper examines how mutual fund investors’ demand for liquidity provision endogenously affects stock liquidity in the equity market. We find that actively managed funds in the US tend to hold less liquidity than their respective benchmarks, which leads them to rely on only a small fraction of liquid stocks when it comes to liquidity demand. Using mutual fund sell transactions, we further show that mutual funds tend to sell more liquid stocks in their holdings when experiencing outflows. Concentrated sales of liquid stocks, however, significantly reduce the liquidity of these stocks, resulting in liquidity deterioration or dry-up among highly liquid stocks in periods of high market-wide liquidity demand. Overall, the results indicate that mutual funds fail to predict the liquidity of the asset at purchase.     

Asset liquidity,business risk,and beta

Extant literature posits that because of leverage, equity beta estimates from a single factor capital asset pricing model based on an equity-only market index are biased. We show analytically that this leverage bias is intimately related to the firm's asset structure per se, the firm's asset liquidity (i.e., cash holdings) and business risk. This is mainly because riskless cash holdings and risky real assets jointly determine the relevant risk for asset pricing. We empirically confirm that asset liquidity and business risk can marginally explain the leverage bias in the cross-section of stocks returns.     

The risk in hedge fund strategies: Theory and evidence from long/short equity hedge funds

Theory suggests that long/short equity hedge funds' returns come from directional as well as spread bets on the stock market. Empirical analysis finds persistent net exposures to the spread between small vs large cap stocks in addition to the overall market. Together, these factors account for more than 80% of return variation. Additional factors are price momentum and market activity. Combining two major branches of hedge fund research, our model is the first that explicitly incorporates the effect of funding (stock loan) on alpha. Using a comprehensive dataset compiled from three major database sources, we find that among the three thousand plus hedge funds with similar style classification, less than 20% of long/short equity hedge funds delivered significant, persistent, stable positive non-factor related returns. Consistent with the predictions of the Berk and Green (2004) model we find alpha producing funds decays to “beta-only” over time. However, we do not find evidence of a negative effect of fund size on managers' ability to deliver alpha. Finally, we show that non-factor related returns, or alpha, are positively correlated to market activity and negatively correlated to aggregate short interest. In contrast, equity mutual funds and long-bias equity hedge funds have no significant, persistent, non-factor related return. Expressed differently, L/S equity hedge funds, as the name suggests, do benefit from shorting. Besides differences in risk taking behavior, this is a key feature distinguishing L/S funds from long-bias funds.