股票市场

  • 详情 引入交易成本的资产配置模型有效性研究—来自中国股票市场的证据
    本文针对投资者所面临的资产配置问题,构建了四个不同规模的投资组合数据库,检验了引入交易成本的多期资产配置模型在中国股票市场的有效性。研究发现,交易成本的存在的确严重影响了模型业绩;相比初始投资组合为0的情形,初始投资组合为市场组合时模型的业绩表现更好;考虑交易成本的多期模型显著改进了单期模型业绩。此外,本文把 Tu和 Zhou[6]的单期组合策略推广到多期情形,得到一个引入交易成本的多期组合策略,并发现该策略在所有最优化策略中业绩表现最好。最后,我们发现,没有一个最优化策略可以超过简单多样化策略。
  • 详情 Market Crowd’s Trading Behaviors, Agreement Prices, and the Implications of Trading Volume (市场群体的交易行为、认同价格以及交易量的内涵)
    It has been long that literature in financial academics focuses mainly on price and return but much less on trading volume. In the past twenty years, it has already linked both price and trading volume to economic fundamentals, and explored the behavioral implications of trading volume such as investor’s attitude toward risks, overconfidence, disagreement, and attention etc. However, what is surprising is how little we really know about trading volume. Here we show that trading volume probability represents the frequency of market crowd’s trading action in terms of behavior analysis, and test two adaptive hypotheses relevant to the volume uncertainty associated with price in China stock market. The empirical work reveals that market crowd trade a stock in efficient adaptation except for simple heuristics, gradually tend to achieve agreement on an outcome or an asset price widely on a trading day, and generate such a stationary equilibrium price very often in interaction and competition among themselves no matter whether it is highly overestimated or underestimated. This suggests that asset prices include not only a fundamental value but also private information, speculative, sentiment, attention, gamble, and entertainment values etc. Moreover, market crowd adapt to gain and loss by trading volume increase or decrease significantly in interaction with environment in any two consecutive trading days. Our results demonstrate how interaction between information and news, the trading action, and return outcomes in the three-term feedback loop produces excessive trading volume which includes various internal and external causes. Finally, we reconcile market dynamics and crowd’s trading behaviors in a unified framework by Shi’s price-volume differential equation in stock market where, we assume, investors derive a liquidity utility expressed in terms of trading wealth which is equal to the sum of a probability weighting utility and a reversal utility in reference to an outcome. JEL Classifications: G12, G02, D83 (长期以来,金融学术领域里的文献只注重价格和收益率,却较少研究交易量。在最近的二十年里,金融学术文献已经开始研究价格和交易量两者与经济基本量之间的相互关系,并且探讨交易量的行为内涵,例如投资者对风险的态度、过度自信、不同观点以及关注程度等等。然而,我们还是对交易量的认识知之甚少。本文根据行为分析,用交易量概率来表示市场群体的交易频率,并且通过我国股市来实证检验涉及交易量与价格之间不确定关系的两种适应性假说。实证结果表明:市场群体在每日交易的时间窗口内除了采用简单的经验法则之外,同时还采用有效的适应性方式来从事股票交易,并且逐步倾向于形成一个结果和认同的资产价格;无论该资产价格是否明显地被高估或低估,市场群体在相互作用和竞争的过程中往往能够形成这样一个稳态的均衡价格。这表明了资产价格不仅包含了基本价值同时还包含了非公开信息、投机、情绪、关注、赌博和娱乐等价值。此外,在任意两个连续交易日之间,市场群体在与市场环境的相互作用过程中,通过交易量的增加或减少来有效地适应盈亏。我们的研究结果说明了在由信息、交易与收益结果三项构成的反馈环中,它们之间的相互作用是如何导致了过度交易的,这其中包含了导致过度交易的各种内外因素。最后,我们假设股票市场中的投资者是通过交易财富来产生流动性效用,它等于概率加权效用与相对于结果为参照系的反转效用之和,从而推导出Shi氏价-量微分方程,将市场动力学行为与群体交易行为协调在一个统一的框架体系。)
  • 详情 Market Crowd's Trading Behaviors, Agreement Prices, and the Implications of Trading Volume (市场群体的交易行为、认同价格以及交易量的内涵)
    It has been long that literature in financial academics focuses mainly on price and return but much less on trading volume. In the past twenty years, it has already linked both price and trading volume to economic fundamentals, and explored the behavioral implications of trading volume such as investor’s attitude toward risks, overconfidence, disagreement, and attention etc. However, what is surprising is how little we really know about trading volume. Here we show that trading volume probability represents the frequency of market crowd’s trading action in terms of behavior analysis, and test two crowd’s trading behavioral hypotheses relevant to the volume uncertainty associated with price in China stock market. The empirical work reveals that market crowd trade in simple heuristics and efficient adaptation, gradually tend to achieve agreement on an outcome or an asset price widely on a trading day, and generate such a stationary equilibrium price very often in interaction among themselves no matter whether it is highly overestimated or underestimated, suggesting that asset prices include not only a fundamental value but also private information, speculative, sentiment, gamble, and entertainment values etc. In addition, market crowd adapt to gain and loss by trading volume increase or decrease significantly in interaction with environment in any two consecutive trading days. Our results demonstrate how interaction between information and news, the trading action, and return outcomes in the three-term feedback loop produces excessive trading volume which includes various internal and external causes. Finally, we reconcile market dynamics and crowd’s trading behaviors in a unified framework by Shi’s price-volume differential equation in stock market where, we assume, investors derive a liquidity utility expressed in terms of trading wealth which is equal to the sum of a probability weighting utility and a reversal utility in reference to an outcome. JEL Classifications: G12, G02, D83 (长期以来,金融学术领域里的文献只注重价格和收益率,却较少研究交易量。在最近的二十年里,金融学术文献已经开始研究价格和交易量两者与经济基本量之间的相互关系,并且探讨交易量的行为内涵,例如投资者对风险的态度、过度自信、不同观点以及关注程度等等。然而,我们还是对交易量的认识知之甚少。本文根据行为分析,用交易量概率来表示市场群体的交易频率,并且通过我国股市来实证检验交易量与价格之间不确定关系中关于群体交易行为的两个基本假说。实证结果表明:市场群体在每日交易的时间窗口内采用简单的经验法则和有效的适应方式来从事交易,并且总是逐步地倾向于形成一个结果和认同的资产价格;无论该资产价格是否明显地被高估或低估,市场群体在相互作用的过程中往往能够形成这样一个稳态的均衡价格,这表明了资产价格不仅包含基本价值同时还包含非公开信息、投机、情绪、赌博和娱乐等价值。此外,在任意两个连续交易日之间,市场群体在与市场环境的相互作用过程中,通过交易量的增加或减少来有效地适应盈亏。我们的研究结果说明了在由信息、交易与收益结果三项构成的反馈环中,它们之间的相互作用是如何导致了过度交易的,这其中包含了导致过度交易的各种内外因素。最后,我们假设股票市场中的投资者是通过交易财富来产生流动性效用,它等于概率加权效用与相对于结果为参照系的反转效用之和,从而推导出Shi氏价-量微分方程,将市场动力学行为与群体交易行为协调在一个统一的框架体系。)
  • 详情 中国股市流动性的风险结构
    流动性影响股票收益的渠道在传统文献中仍需进一步厘清,本文采用随机折现因子的 方法构建了SDF‐LCAPM 模型,将流动性影响股票收益的渠道分为两个:第一个渠道是股票 自身的流动性特征直接影响股票收益;第二个渠道为流动性是系统风险的组成部分,影响股 票的收益。SDF‐LCAPM 模型提出了将流动性影响资产收益的两个渠道联接的框架,并解开了 流动性的波动性与资产收益负向关系之谜,解释了系统流动性与股票收益率对市场流动性的 敏感度不被定价可能的原因,还发现了流动性与资产收益的协方差在资产定价中有重要的作 用。根据SDF‐LCAPM 模型我们实证发现,不同类型的股票流动性特征和流动性风险对收益 率影响的程度是不同的,这一发现可为投资者流动性风险管理提供参考依据。除此而外, SDF‐LCAPM 模型应用在中国股票市场上,可以提高投资组合的Sharpe 比率,具有一定的应 用价值。
  • 详情 现金流信息、现金流风险与股票收益定价研究--基于中国股票市场的检验
    本文对现金流信息、现金流风险在股票收益中的定价关系进行了深入研究,建立了包含现金流信息的多因素股票非预期收益定价模型,并采用2002年1月至2011年4月间中国股票市场的有关交易数据、机构收益预测数据和财务数据,来检验理论模型和实证模型的预测,发现:(1)由证券分析师盈余预测修正来估计出的正现金流信息对股票非预期收益、股票实际收益、股票超额收益均具有稳健的解释能力;(2) 由证券分析师盈余预测估计出的现金流风险反映了股票的系统风险,可以对股票预期收益定价;(3) 在解释股票超额收益方面,由现金流信息、现金流风险、分析师跟踪人数与宿成建(2012)三因素模型构成的多因素变量模型优越于Fama和French(1996)三因素模型变量与现金流信息、现金流风险构成的多因素模型;
  • 详情 Market Crowd Trading Conditioning, Agreement Price, and Volume Implications (市场群体的交易性条件反射、接受价格以及成交量的涵义)
    It has been long that literature in finance focuses mainly on price and return but much less on trading volume, even completely ignoring it. There is no information on supply-demand quantity and trading volume in neoclassical finance models. Contrary to one of the clearest predictions of rational models of investment in a neoclassical paradigm, however, trading volume is very high on the world’s stock market. Here we extend Shi’s price-volume differential equation, propose a notion of trading conditioning, and measure the intensity of market crowd trading conditioning by accumulative trading volume probability in the wave equation in terms of classical and operant conditioning in behavior analysis. Then, we develop three kinds of market crowd trading behavior models according to the equation, and test them using high frequency data in China stock market. It is hardly surprising that we find: 1) market crowd behave coherence in interaction widely and reach agreement on a stationary equilibrium price between momentum and reversal traders; 2) market crowd adapt to stationary equilibrium price by volume probability increase or decrease in interaction between market crowd and environment (or information and events) in an open feedback loop, and keep coherence by conversion between the two types of traders when it jumps and results in an expected return from time to time, the outcome of prior trading action; 3) while significant herd and disposition “anomalies” disappear simultaneously by learning experience in a certain circumstance, other behavioral “anomalies”, for examples, greed and panic, pronounce significantly in decision making. Specifically, a contingency of return reinforcement and punishment, which includes a variety of internal and external causes, produces excessive trading volume. The behavioral annotation on the volume probability suggests key links and the new methods of mathematical finance for quantitative behavioral finance.长期以来,金融的学术文献主要关注价格和回报率,很少考虑甚至完全忽视了交易量。新经典金融模型就没有供需量和交易量的信息。然而,与新经典框架理性投资模型的预计结果不同,交易量在世界的股票市场上是非常大的。我们基于Shi的价-量微分方程,根据行为分析中的经典性和操作性条件反射,提出了交易性条件反射的概念,并且用该方程中的累计交易量概率来计量市场群体交易性条件反射的强度。由该方程,我们得到三种市场群体的交易行为模型,并且用我国股市的高频数据进行实证分析。不难发现:1)市场群体在相互作用的过程中普遍地表现出相互一致的行为特征,趋势和反转交易者之间存在着一个大家都能够接受的稳态均衡价格;2)交易行为有时会导致稳态均衡价格出现跳跃、带来预期收益率,这时,市场群体在开放的反馈环中,通过与环境(或信息和事件)之间的相互作用,由成交量概率的增加或减少来适应该均衡价格的变化,趋势和反转交易者也会通过相互转换保持市场群体行为的相互一致性; 3)尽管在某特定环境下市场群体通过学习实践,羊群和处置行为同时消失了,但是其他行为“异象”,例如贪婪与恐慌,在决策中却表现的十分显著。特别地,收益率强化和惩罚过程,其中包含各种内外因素,导致过度交易量。累计交易量概率的行为诠释为计量行为金融学提供了关键性的纽带作用和数学金融的新方法。
  • 详情 热钱流动对资产价格波动和金融脆弱性的影响
    本文在对热钱流动导致资产价格波动进而影响金融脆弱性的进行系统论述的基础上,基于国内2003年1月至2011年12月月度股票收益率和房屋价格指数,利用SVAR模型研究了热钱对我国股票市场和房地产市场价格的影响。结果表明,热钱对股票市场和房地产市场有着长期均衡关系,热钱流入显著推动了股票价格指数上涨,并得到股票收益率波动的30%是由热钱异动所致,但热钱对房屋价格指数影响相对较小,表现在房价变动中20%与热钱流动有关;另一方面发现股价上涨同时对房地产市场价格有着正向影响,被抬高的房价会进一步吸引热钱的流入。基于热钱对金融稳定与脆弱性的影响,提出了完善人民币汇率和利率机制,合理疏导等治理热钱的政策建议。
  • 详情 策略转换与资产价格不对称波动
    本文结合最近的实证文献所描述的市场表现,脱离本领域典型的投资者非理性研究,以投资者交易行为作为中间环节,对资产价格波动非对称性这个经典问题迚行新的阐释。本文从交易者个体自适应角度出发,借鉴Hommes等人的思想,在经典的圣塔菲人工股票市场上迚行简单的修改,找到了造成资产价格波动丌对称新的因素——投资者策略转换倾向的时变性。本文通过新兴的计算实验方法迚行建模,实验,最后通过EGARCH模型迚行实证检验,证明本文找到的因素显著地影响资产价格波动丌对称性。
  • 详情 生命周期下家庭股票市场参与研究——基于2005-2007年中国居民家庭调查数据
    中国经济的高速发展推动广大普通居民家庭的财富得以快速积累,使更多的普通投资者参与到股票和基金等金融资产的投资中,此背景之下在如何通过合理的资产配置实现家庭财富的保值与增值就成为了越来越重要的问题。通常投资者的投资目的和投资策略会因其处于生命周期的不同阶段或不同年份而不尽相同,而广大普通家庭投资组合选择中所表现出的年龄效应和时间效应汇聚所产生的合力,更会对整个金融市场造成巨大影响。以家庭股票市场的参与选择作为研究视角,本文选用2005-2007年来自全国23个城市的3870个家庭样本,通过直接参与和间接参与两种指标,分析了生命周期效应和年份效应以怎样的方式影响普通家庭的参与决策。首先,研究发现即使控制了财富积累能力和教育程度等因素后,家庭直接参与市场的选择依旧表现出一定的年龄效应,中国居民家庭股票市场的直接参与率随年龄呈现出“钟形”分布。此外,在数据样本的时间区间家庭参与率有明显提高,这表明越来越多的中国居民开始持有股票等风险资产,投资组合逐渐从简单变得复杂。
  • 详情 基于投资者关注的媒体报道影响投资行为的实验研究
    媒体报道对股票市场的影响已经得到研究者的广泛认可,通过影响投资者关注程度影响其投资行为是一个可能的机制,但是注意力效应的难以分离和注意力的难以量化是相关研究的重要障碍。本文通过一个证券市场实验对投资者关注程度进行了定量测量,进而检验了媒体报道对投资者关注和后续投资行为的影响,发现媒体报道的数量与投资者关注程度显著正相关,从交易行为上来看,媒体报道更多也即投资者关注度更高的股票获得了更多的交易资金、其成交量也显著高于关注度低的股票,说明媒体报道作为注意力配置机制确实影响着投资者的行为。