股权溢价研究

我国股票市场具有自己的独特性,是否存在股权溢价一直是国内研究学者争论的问题.本文选取我国股票市场1991年到2008年的数据进行股权溢价的计算,并以基于消费的资产定价模型为基础,考虑消费对股权风险溢价的影响,验证我国是否存在股权溢价,结果发现我国存在很高的风险溢价,而模型却不能对其进行解释,主要是消费和风险收益的相关性很低。通过对我国股权溢价的研究,提出研究风险溢价,对投资者和政府决策的意义重大.对投资者来说,关注分析股权溢价,能够作为合理分配资产进行投资的一种参考方式;对政府来说,监管股票市场需要首先了解股票市场的特性,在此基础上,合理调控股票市场,完善市场。     

有限理性条件下的资产定价理论综述

传统的资产定价理论基于新古典经济学的研究框架,假定投资者是完全理性的,在这个基础上研究资产收益率的决定。然而,完全理性的投资者在现实中并不存在,并且基于完全理性的分析不能完全解释市场上的种种异象。与传统的研究方法不同,有限理性的资产定价理论认为:投资者是有限理性的,应按照一些基于经验的认知捷径来形成对未来的认识,并以此为基础进行投资。通过引入这种更符合现实的投资者,有限理性的资产定价理论研究资产收益率的决定,试图更好地解释各种市场现象。     

投资者有限关注与股票名称的“地名效应”——来自粤港澳大湾区规划发布的证据

股票名称作为上市公司公开的身份名片,其如何影响投资者行为和资产定价值得引起关注。基于投资者“有限关注”理论,借助粤港澳大湾区规划发布这一外生冲击事件,采用事件研究法检验股票名称的“地名效应”对上市公司股票市场反应的影响发现,在面对外部宏观地域性利好消息时,投资者存在非理性的选择性关注行为,具体表现为,股票名称中含有相关地域信息的股票市场反应更强,印证了投资者有限关注理论。进一步考虑公司横截面差异的影响发现,公司成长性越高、分析师跟踪数量越多、机构投资者持股比例越高,越能有效降低投资者有限关注行为。同时,相比异地投资者,本地投资者有限关注更弱,投资决策更理性。因此,投资者应该合理评估上市公司市场价值,理性投资,抑制因“地名效应”导致的非理性投资行为。     

基于投资者异质性信念的证券定价模型——对我国股票市场价格的实证检验

投资者异质性信念的相互作用影响着证券价格,证券市场上的各种证券需求与供给关系,往往表现为投资者各种不同信念的对抗和交融。本文以悲观信念（看多）和乐观信念（看空）之间的相互作用为例,研究了异质性信念对资产均衡定价的影响,并以我国股票市场的机构投资者信念为对象进行了实证检验,得出我国股票市场投资者信念与证券价格相互作用的结论。本文的建议是在投资过程中,准确分析市场中投资者的异质性信念结构,尤其是资金雄厚的机构投资者的信念结构至关重要。     

投资者对经济基本面的认知偏差会影响证券价格吗?——中美证券市场对比分析

本文通过放松Lucas(1978)资本资产定价模型的完全理性假设,构建了投资者的经济基本面认知偏差对证券价格影响的计量模型。当投资者主观认知和市场实际运行机制存在偏差时,该模型能较好地解释诸如消费增长率同股权溢价的相关性、累积超额收益等传统资产定价模型无法量化的诸多中国股市难题。本文还推导出了适用于非理性期望的广义矩估计方法(GMM),克服了现有GMM方法只能在完全理性期望下使用的局限性。基于该方法,本文以中国和美国为例,模拟检验了投资主体的不同认知偏差对股价和债券价格的差异性影响程度。结果显示,中美投资者的主观预期形式并不完全相同。美国投资者对经济基本面信息均值的变化反应较敏感;而中国投资者却对经济基本面波动的变化反应较敏感。该结果从认知偏差角度解释了中国股价长期背离经济基本面的现象,为政府规范股票市场的发展,促进股市服务实体经济提供了政策启示。     

投资者情绪、经济政策不确定与股市流动性

文章以2010年1月至2021年3月为样本期,运用SVAR模型探究投资者情绪、经济政策不确定与股市流动性之间的关系。实证结果表明：当经济政策不确定增加时,投资者不再愿意持有流动性资产,股市流动性急剧降低;随着政策实施效果逐渐展现,长期投资者将预期看好股市,股票市场流动性快速增加。同时,经济政策不确定性的增加会引起投资者的恐慌,这是因为政府政策实施存在时滞。但投资者情绪会因为国内政治环境的稳定和投资者预期看好政策执行的效果而逐渐回归理性。当经济政策的不确定性较高时,即使投资者情绪高涨,投资者也会先观望市场情绪,谨慎投资,导致短期内股票市场流动性降低。     

流动性、生命周期与投资组合相异性——中国投资者行为调查实证分析

本文采用Probit和Tobit模型对中国居民的股票市场参与和投资组合的影响因素进行了分析,主要有以下的实证发现:首先,不流动性资产特别是房地产的投资显著影响了投资者的股票市场参与和投资组合,而且影响以“替代”效应或者说“挤出”效应为主。其次,投资者在进行投资组合时极少利用股票市场对其未来现金流所承担的风险进行对冲,也就是说,中国居民投资的“生命周期效应”不明显;第三,中国居民投资的“财富效应”非常显著。财富的增加既增加了居民参与股票市场的概率,也增加了居民参与股票市场的深度。     

中国非理性股市的形成原因探析

20 0 0 年 10月《财经》杂志发表《基金黑幕》一文。吴敬琏在 10月 2 9日、 12月 3 0日、 2 0 0 1年 1月 12日分别接受中央电视台《经济半小时》和《对话》节目记者的采访 ,发表了他对股票市场的一系列的看法。这些观点和看法引来了无数评论和诘难。厉以宁、董辅礻乃、萧灼基、吴晓求、韩志国等著名专家“全面反击吴敬琏关于资本市场的种种言论”。综观这次论争 ,似乎并没有说清理性的股票市场和非理性的股票市场的区别。本文就此问题进行讨论。一、理性市场的股票定价机制投资者行为是否理性 ,是市场理性与否的重要区别。投资者行为理性是指投资者首先要根据上市公司的各种资料分析股票的内在价值 ,然后据此进行股票投资交易。在分析理性市场与非理性市场区别之前 ,先介绍两个基本模型。(一 )关于股价决定的市场模型在股票市场中 ,股票价格P与场内可用资金总量M、场内可流通股票总量S、场内资金在单位时间内通过股票交易在不同投资者之间转移的次数VM、可流通股票在单位时间内通过股票交易在不同投资者之间转移的次数VS 有密切的关系。即 :P =MVM/SVS (1)(1)场外资金的流入 ,资金流动速度的加快或者股票流动速度的减...     

A股市场FF模型适用性的实证性研究

对三因素模型在我国证券市场的适用性问题,即股票期收益率与市场溢价因素、公司规模因素和账面市值比因素的关系问题进行了实证研究。根据我们分析的样本,得出以下结论：总体而言,三因素模型在我国股票市场是适用的,可以作为一个方便实用的工具来帮助投资者对中国股票市场进行分析和预测;中国股票市场具有规模效应和账面市场价值比效应,价值型股票的收益率高于成长型股票的收益率。     

艺术品的金融属性：投资收益与资产配置*

本文基于2000—2014年中国艺术品拍卖市场近现代国画的微观数据,在资产配置中引入市场交易机制中的佣金变量,加入艺术品市场规模约束,采用重复交易法实证计量嵌入艺术品市场的投资收益特征并量化其资产配置效应,以测度其市场功能。优质的艺术精品具备金融资产风险和收益的基本特征,本文对艺术品资产与资本资产定价模型的适应性进行讨论。研究表明：在样本期内,剔除通胀和佣金成本因素后收益率更加贴近现实,中国艺术品投资的实际收益率水平为1308%,表现出高于欧美市场的投资溢价;艺术品投资与传统的股票、债券等金融资产之间表现出相对独立性,并能有效改善投资者资产组合的风险边界,可以成为资产配置优化和多样化的重要选择。中国艺术品市场的长期稳健发展将为投资者提供更多的资产优化产品和工具。     

过度自信、流动性和资产定价

本文研究了过度自信的投资者在一个多阶段金融市场中是如何影响均衡价格和投资者要求的期望收益的.结论表明,由于投资者过度自信,容易低估风险,从而在一段时期内会使得价格急剧上升.投资者人数实际上是股票市场流动性的一个表征,我们的结论表明,由于过度自信的投资者的存在,他们实际上充当了流动性提供者的角色,从而使得一段时期内即使对理性投资者来说,依然导致了风险的暂时降低,他们也会接受比较高的资产价格,要求相对比较低的期望收益.     

Beauty contest,bounded rationality,and sentiment pricing dynamics

We present a dynamic asset pricing model that incorporates investor sentiment, bounded rationality and higher-order expectations to study how these factors affect asset pricing equilibrium. In the model, we utilize a two-period trading market and investors make decisions based on the heterogeneous expectations principle and the “sparsity-based bounded rational” sentiment. We find that bounded rationality results in mispricing and reduces it in next period. Investor sentiment produces more significant effects than private signals, optimistic investor sentiment increases hedging demand, thus causing prices to soar. Higher-order investors are more rational and attentive to the strategies of other participants rather than private signals. This model also derives the dampening effect of higher-order expectations to price volatility and the heterogeneity expectation depicts inconsistent investor behavior in financial markets. In the model, investors' expectations about future price is distorted by their sentiment and bounded rationality, so they obtain a biased mean from the signal extraction.     

控股股东道德风险与公司现金策略

本文借鉴Myers & Majluf(1984)的模型框架,从控股股东利益最大化的视角构建了公司发行股票为投资项目融资的决策模型。本文模型分析表明,公司控股股东会选择在其自身利益增加的情况下发行股票,但这有可能损害公司原有中小股东的利益。控股股东的这种道德风险将被市场所预期,从而会对公司融资行为形成约束。在这种因控股股东道德风险所引起的融资约束下,公司现金持有策略会发生变化。控股股东出于利益侵占动机增强对现金资产的偏好,导致公司现金—现金流敏感度上升,而公司增持现金的价值效应较低。在实证检验中,本文以2003—2009年沪深两市非金融类A股上市公司作为分析样本,用终极控股股东控制权/现金流权两权分离程度代表公司控股股东利益侵占动机的强弱。检验结果表明,在终极控股股东两权分离程度较大的情况下,公司现金—现金流敏感度较高而现金变动的价值较低,这证实了本文的理论假说。     

Information Markets and the Comovement of Asset Prices

Traditional asset pricing models predict that covariance between prices of different assets should be lower than what we observe in the data. This paper introduces markets for information that generate high price covariance within a rational expectations framework. When information is costly, rational investors only buy information about a subset of the assets. Because information production has high fixed costs, competitive producers charge more for low-demand information than for high-demand information. The low price of high-demand information makes investors want to purchase the same information that others are purchasing. When investors price assets using a common subset of information, news about one asset affects the other assets' prices; asset prices comove. The cross-sectional and time-series properties of comovement are consistent with this explanation.     

股民过度交易了么?——基于中国某证券营业厅数据的研究

本文利用中国某证券营业厅个人股票交易数据,验证了中国股票市场上存在的过度交易现象。文章发现,对应着不同的股票持有期,投资者买进的股票在买进后一定时间内的收益率,低于他们出售的股票在售出后相同时间长度内的收益率。这一结论在股票市场整体走势截然不同的两个阶段,对于不同投资规模、不同交易频率投资者都是成立的。而且,在剔除正常交易需求后上述结论依然成立。这说明股民大量的交易决策是错误的,对于理性投资者来讲这些交易原本不该发生。从这个意义上讲,可以认为中国股民存在着过度交易倾向。通过对不同性别投资者投资行为的比较,我们发现男性投资者过度交易的程度要高于女性投资者。结合心理学领域的研究成果,这在某种程度上意味着中国股市投资者过度交易现象与过度自信是相关的。     

The possibility of informationally efficient markets

A rational expectations equilibrium with positive demand for financial information does exist under fully revealing asset price—contrary to a wide-held conjecture. Whereas a continuum of investors is inconsistent with fully revealing equilibrium, finitely many investors with average portfolios demand information in equilibrium if they can adjust portfolio size in an additive signal-return model. More information diminishes the expected excess return of a risky asset so that investors who only have a choice of portfolio composition or whose asset endowments strongly differ from the average portfolio are worse off. Under fully revealing price, information market equilibria both with and without information acquisition are Pareto efficient.     

Rational inattention,long-run consumption risk,and portfolio choice

This paper explores how the introduction of rational inattention (RI) – that agents process information subject to finite channel capacity – affects optimal consumption and investment decisions in an otherwise standard intertemporal model of portfolio choice. We first explicitly derive optimal consumption and portfolio rules under RI and then show that introducing RI reduces the optimal share of savings invested in the risky asset because inattentive investors face greater long-run consumption risk. We also show that the investment horizon matters for portfolio allocation in the presence of RI, even if investment opportunities are constant and the utility function of investors is constant relative risk aversion. Second, after aggregating across investors, we show that introducing RI can better explain the observed joint dynamics of aggregate consumption and the equity return. Finally, we show that RI increases the implied equity premium because investors under RI face greater long-run consumption risk and thus require higher compensation in equilibrium.     

Water as an investment: liquid yet illiquid!

The water industry is in great need of further large investments to address existing severe water shortages worldwide which requires the participation of private sector investors. This industry is heavily infrastructure based and is therefore saddled with fixed assets-in-place or illiquid assets. This exposes the industry to what is termed as ‘illiquidity risk’, and hence, investors in this industry should be compensated for bearing this risk with an appropriate return premium (i.e. extra return). In this study, we provide evidence as to whether illiquidity risk indeed significantly affects returns in this industry. We examine the case of all 76 firms that compose the five major global water indices. After controlling for other factors that impact on returns, our results suggest that asset illiquidity is positively associated with stock returns. Specifically, water firms with a larger proportion of illiquid assets-in-place are observed to have greater stock returns than those with a smaller proportion of illiquid assets. Our results have important implications for the financing of water-related projects particularly those which involve the participation of investors from the private sector.     

Foreign direct investment, political resentment and the privatization process in eastern Europe

Foreign direct investment has been disappointingly low in eastern Europe, which has been reluctant to make existing assets available to foreign investors. To mitigate any such resentment, we propose a participation model in which foreign investors compete for joint venture contracts. Host governments contribute existing assets and receive non-voting stocks. Foreign investors, contributing capital and know-how, receive voting shares and control of operational decisions.{}This has several advantages over the cash sale of assets to foreigners. First, stock flow problems are eased, raising both asset prices and FDI flows. Second, by retaining some stake in the firm, transition countries share in the risk premium. Third, governments can hand over their shares to households, creating private collateral to foster new small businesses. Fourth, and crucially, compared to cash sales the auction of participation contracts offers higher privatization revenues in cases where governments cannot assess investors' knowledge and abilities. This reduces the risk of selling the family silver too cheaply, and should alleviate the host countries' resentment.     

Do Irrational Investors Destabilize?

In a financial market where all investors have valuable private information, full rationality requires that investors have an unlimited ability of figuring out the equilibrium model. Instead, I assume that due to a lack of knowledge or experience, some investors do not know the equilibrium model and use only their private information in forming their demand. By investigating the investment behavior of these “boundedly rational” investors and contrasting it with that of the rational ones, I find that in a market where the two kinds of investors coexist, it is the boundedly rational investors who contribute to price stability. The welfare implication is that, although each investor benefits from conditioning his asset demand on the information transmitted by the equilibrium price, it can happen that all investors lose by doing so because the equilibrium price becomes too volatile.