我国证券市场投资者行为分析

由于投资者间异质性假设可以对金融异象给出合理的解释,因此异质性成为金融研究的热点。借鉴已有文献,从投资者的交易行为入手研究我国证券市场的异质性投资者,把投资者分为理性交易者、正反馈交易者和内在价值交易者。理论上,我们看到资产的收益与各类投资者所占的比例密切相关。实证分析中,以深圳成分指数为资产,发现在长期内,深圳证券交易市场存在理性交易者、内在价值交易者,不存在反馈交易者;但短期内,深圳证券市场存在反馈交易者。     

股权分置改革后我国证券市场有效性研究——基于非预期非流动性新信息视角

基于非预期非流动性新信息视角,本文研究了股权分置改革后我国证券市场效率,比较了不同的市场态势下非预期非流动性对股票收益的影响,并且研究了投资者能否基于当期的非预期非流动性新信息进行套利。实证结果表明:我国上证A股市场中,熊市阶段发挥主要作用的是非预期非流动性;市场对非流动性新信息反应不足,我国上证A股市场存在套利机会。     

投资者情绪对市场风险价格影响

本文利用我国证券市场统计数据研究了个体和机构投资者情绪对风险市场价格（MPR）的影响,实证结果证明了市场对波动的反应是异质性的,并且受投资者情绪变化的影响。具体来看,将投资者情绪分解成理性和非理性成分后,非理性乐观情绪的增加将导致MPR明显的下降,但理性情绪的变动不会对MPR有明显的影响。这意味着当市场投资者情绪是由基础价值变化来决定的时候,市场风险价格不会发生变化。进一步的VAR脉冲响应函数分析结果显示,非理性的乐观或悲观情绪并不受理性情绪波动的影响,这意味着非理性情绪不是由基础风险因素决定的。     

开放条件下原油期货市场投机和套利行为的风险度量

期货市场与投资者行为紧密联系,并相互影响。投机者和套利者是提供流动性的重要力量,投机和套利也是期货市场的主要交易行为类型。基于投资者行为对市场的影响具有一致性的特点,本文以开放市场的原油期货为研究对象,通过考虑便利收益和自适应预期条件,进一步完善了传统的投机与套利分析模型,并定量分析了投资者的投机和套利行为对原油期货价格形成机制的影响。市场不同的参与主体应采取符合自身特色的交易和风险防范策略。     

噪声交易者生存机制研究——基于理性交易者和噪声交易者生存模型的分析

本文从行为金融理论发展的大背景和我国证券市场的实际出发,以噪声交易者生存机制为研究主题。首先介绍了行为金融理论的噪声交易理论;接着结合我国证券市场的实际情况,提出了“理性交易者和噪声交易者模型”,对我国噪声交易者的生存机制进行深入的剖析。然后用平面和立体图形解析优先噪声交易者获利机制和生存的持续性。结果表明跟进噪声交易者给优先噪声交易者带来信息优势和高预期收益的同时,也扩大了整个市场的价格波动程度,需加强市场监管,培育有影响力的理性交易投资群体。     

交易偏好、公司特征与股票收益——基于我国个体投资者交易数据的实证检验

噪音交易是影响股票收益的重要风险因素,对于那些噪音交易活跃、套利成本较高的股票,噪音交易者需求变动对股票价格的影响更为显著。本文以我国个体投资者2006年-2011年的交易数据为样本,按照公司特征对样本股进行分组,发现个体投资者对小盘、低价、高账面市值比、高收益和高特质波动的股票具有更强的交易偏好,且对股票需求的变动存在显著的系统相关性,个体投资者需求变动对股票价格的影响程度与其交易偏好有关。本文的研究结论为个体投资者交易行为理论提供了有价值的实证支持。     

行为金融学与证券市场中的噪声交易理论综述

在标准金融理论中,噪声交易不会对证券价格产生影响,但是近年来我国证券市场中的各种异象和投资者的非理性表现均证实非理性交易者行为可对证券市场产生影响,因此以投资者有限理性为前提的噪声交易理论被引入到对我国金融市场的研究中来。本文首先回顾了行为金融学的兴起和发展,其次综述了行为金融学范畴热门理论--噪声交易理论,最后对行为金融学与噪声交易理论的发展前景作出了展望。     

行为金融学与证券市场中的噪声交易理论综述

在标准金融理论中,噪声交易不会对证券价格产生影响,但是近年来我国证券市场中的各种异象和投资者的非理性表现均证实非理性交易者行为可对证券市场产生影响,因此以投资者有限理性为前提的噪声交易理论被引入到对我国金融市场的研究中来。本文首先回顾了行为金融学的兴起和发展,其次综述了行为金融学范畴热门理论--噪声交易理论,最后对行为金融学与噪声交易理论的发展前景作出了展望。     

异质性交易策略与股价崩盘风险研究

基于2011—2022年中国A股交易数据，研究了异质性交易策略对股价崩盘风险的影响。研究表明，个人投资者的当期情绪以及机构投资者的前期情绪，能够显著影响风险资产特质收益率的波动：个人交易者倾向于做出骑乘泡沫行为，而机构交易者则倾向于利用市场噪声情绪推高风险资产价格并提前变现离场。同时，在对股价崩盘风险和异质性交易策略之间可能存在的系统性断点进行门限检验后发现，机构投资者的相对力量效应对风险资产价格波动的影响程度存在门限点。当机构投资者的相对力量效应超过特定的阈值点时，股价长期崩盘风险会随着相对力量效应的提高而降低；而当个体交易者在市场上占据绝对主导、机构交易者相对力量降低时，股价长期崩盘风险会提高。因此，有效引导交易者对风险资产的需求回归价值面本身，避免出现噪声蛊惑和诱导交易，是有效防范化解金融交易风险的关键。     

政策变化对证券市场中小投资者行为的影响分析

由于我国证券市场受政策因素影响显著、股票的市场政策干预过于频繁,致使投资者收集信息的成本过高,导致我国投资者存在较成熟市场投资者更为严重的心理偏差.本文通过博弈模型分析了政策变化对中小投资者行为的影响:在信息完全的条件下,双方皆为理性交易者,信息政策干预不会引发羊群行为,因此不会导致股市过度波动,政策干预短期和长期内皆有效.在不完全信息条件下,博弈一方为噪音交易者,信息政策干预引发羊群行为,导致股市过度波动.     

An empirical investigation of large trader market manipulation in derivatives markets

Using account-level transaction data in options and futures markets, we investigate the existence of market manipulation, which is the ability of large traders to trade strategically, impacting prices and making abnormal profits. First, large trader’s option positions have a quantity impact on the underlying asset’s price. Second, large traders generate significantly positive alphas from trading options and futures. Among the different investor types, proprietary dealers generate the largest positive alphas. Third, these abnormal returns are consistent with strategic trading and cross-market manipulation. The evidence supports market manipulation across the options and futures markets, but not within the futures market itself.     

Who is the more overconfident trader? Individual vs. institutional investors

Guided by the Gervais and Odean (2001) overconfident trading hypothesis, we comprehensively investigate the trading behavior of individual vs. institutional investors in Taiwan in an attempt to identify who is the more overconfident trader. Conditional on the various states of the market, on market volatility, and on the risk level of the securities they trade, we find that both individual and institutional investors trade more aggressively following market gains in bull markets, in up-market states, in up-momentum market states, and in low-volatility market states and that only individual investors trade more in riskier securities following market gains. More importantly, we find that individual investors trade more aggressively following market gains in the three conditional states of the market and in high-volatility market states than institutional investors. Also, individual investors trade more in relatively riskier securities following gains than institutional investors. These findings provide evidence that individual investors are more overconfident traders than institutional investors.     

A Test of the Modigliani‐Miller Invariance Theorem and Arbitrage in Experimental Asset Markets

Modigliani and Miller show that the total market value of a firm is unaffected by a repackaging of asset return streams to equity and debt if pricing is arbitrage‐free. We investigate this invariance theorem in experimental asset markets, finding value‐invariance for assets of identical risks when returns are perfectly correlated. However, exploiting price discrepancies has risk when returns have the same expected value but are uncorrelated, in which case the law of one price is violated. Discrepancies shrink in consecutive markets, but persist even with experienced traders. In markets where overall trader acuity is high, assets trade closer to parity.     

投资者教育能提高投资者理性水平吗?

本文以投资者对公允价值的认知偏差程度作为理性水平的替代指标,在进行调查研究的基础上,使用李克量表对投资者的理性水平进行了分析。根据关于对投资者理性水平调查结果,本文对投资者进行了关于公允价值信息的教育和模拟投资实验;通过对比投资者接受教育前后的理性水平,并以之为解释变量,对实验过程中的股价信息含量进行了检验。实证研究发现,投资者对公允价值的认知水平的变化能够显著影响股价信息含量,说明加强投资者对于市场环境的认识有助于提高投资者的理性水平,从而有助于增强我国证券市场的有效性。     

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.     

投资者理性预期、流动性约束与股价崩盘传染研究

“传染性”是股价崩盘三大基本特征之一,会加剧股价崩盘负面影响,甚至引发系统性金融风险,因此,本文重点关注股价崩盘传染机制研究。首先,本文基于两阶段理性预期均衡模型,提出股价崩盘传染两大假设,即投资者理性预期与流动性约束导致传染;其次,基于2000-2016年全球28个国家或地区资本市场数据,实证检验股价崩盘传染机制和传染渠道。研究显示:(1)投资者理性预期、流动性约束会导致股价崩盘发生传染;(2)股价崩盘事件会在资本市场关联国家或地区传染;(3)提高资本市场信息透明度、加强金融管制有助于降低受关联国家或地区股价崩盘传染。     

Asymmetric investor behavior between buyside and sellside: Evidence from investor classes in the Sri Lankan stock market

Using unique trading data for investor classes from Sri Lanka, this study finds asymmetric investor behavior between buyside and sellside in large trades. Investors are positive feedback traders on the buyside and contrarians on the sellside. Domestic investors exhibit more feedback and contrarian behavior than foreign investors, suggesting that foreign investors are more informed on the buyside and less informed on the sellside. Individuals are more feedback and contrarian traders than institutions. Foreign institutional investor sales do not precede, coincide with, or lead to significant returns. Trades do not lead to price momentum or reversals, but leave a permanent positive price effect.     

合谋操纵与散户跟风的演化博弈分析

本文通过构造一个合谋操纵和散户跟风的双种群双策略的演化博弈模型,从规范经济学角度研究了合谋账户与散户之间的演化博弈,分析了合谋操纵者何时会选择操纵、散户是否会跟风、监管对市场操纵的影响以及市场环境如何影响合谋操纵者和散户的行为等问题。为追求利益最大化,拥有资金优势的合谋者具有操纵市场的动机;合谋者操纵市场行为损害了一些跟风散户的利益,一定程度上也会减少散户跟风。基于此,本文认为,应当通过完善法制,保持监管高压态势,加强投资者教育和投资者适当性管理,完善套利制度等,应对合谋操纵和散户跟风行为。     

Large traders,hidden arbitrage,and complete markets

This paper studies hidden arbitrage opportunities in markets where large traders affect the price process, and where the market is complete (in the classical sense). The arbitrage opportunities are “hidden” because they occur on a small set of times (typically of Lebesgue measure zero). These arbitrage opportunities occur naturally in markets where a large trader supports the price of some asset or commodity, for example corporate stock repurchase plans, government interest rate or foreign currency intervention, and price support by investment banks in IPOs. We also illustrate immediate arbitrage opportunities generated by usual market activity at specific points in time, for example the issuance date of an IPO or the inclusion date of a new stock in the S&P 500 index.     

Can earnings fixated investors survive in a competitive securities market? Implications for sustained price anomalies and mark-to-market accounting

We model the dynamic survival of earnings fixated investors in a competitive securities market that allows for learning and arbitrage and that is populated by heterogeneous investors. Our model is distinct from those based on aggressive trading by overconfident investors. We prove that in the absence of noise traders, rational investors will drive out earnings fixated investors from the market in the long-run. More interestingly, we show that in a market with noise traders, some proportion of earnings fixated investors survive in long-run equilibrium for all feasible model parameter values. Furthermore, under no circumstances can the earnings fixated investors be driven out of the market completely. On the contrary, for some parameter values, the earnings fixated investors drive out the rational investors entirely. These results rationalize the long-run sustainability of common pricing anomalies. They also highlight potential benefits to society of mark-to-market accounting.