本文基于理性预期框架研究了卖空约束对市场质量(包括流动性、私人信息的揭示程度以及波动性)以及资产价格的影响。研究结论表明,与卖空约束不起作用时相比,卖空约束起作用时进入市场的私人信息总量更少,信噪比更低,因而价格的信息含量(或信息效率)更低,这将使得风险资产供给量的不确定性对价格的冲击更大,即相同数量的指令对其价格变化的影响更大,并且均衡价格对私人信息的反应程度更弱,因而卖空约束起作用时的市场质量更差,表现为流动性更差、私人信息揭示程度更低、波动率更高。而随着不受卖空约束而进入市场的知情交易者比例增大,市场质量会逐渐转好。同时,卖空约束起作用时进入市场的私人信息总量减少会导致市场信息不对称程度提高,使得交易者平均意义上要求更高的预期收益率作为补偿,从而最后的均衡资产价格不是高估而是下跌。研究结果为Boehmeretal.(2009)等关于卖空约束的最新实证研究结果提供了较好的理论支撑。

本文通过构造恒生指数看涨期权的动态delta中性组合估计了香港股票市场的波动率风险溢酬,并对其时变的特征和影响因素进行了分析。我们发现,香港股票市场上的确存在显著为负的波动率风险溢酬,说明香港市场上的波动率的确是随机的,是市场中存在的另一个风险源。而香港投资者是厌恶波动率风险的,并通过购买股指期权规避这一风险,香港市场上的股指期权并非股票现货的冗余证券。不仅如此,香港股票市场上的波动率风险溢酬还是时变的,其最重要的影响因素是股票现货市场的波动率,股市当前的波动率越大,投资者对未来波动的预期和风险厌恶程度越高,越愿意为规避波动率风险支付更高的风险溢酬。

鉴于目前现代风险测度未考虑极端事件,本文借助极值理论对中国股市收益的GEV分布和GP分布进行了估计和拟合,并对不同置信水平下的VaR进行估计和检验。实证研究表明,GEV分布和GP分布均能对上证指数和深圳成指日收益序列做出较好的拟合,两种收益序列均具有显著的尖峰厚尾分布特征,而且右尾均比左尾更厚,基于GEV分布和GP分布的VaR测度均比正态分布更优,而且GP分布比GEV分布更优。

纵观国内外资本市场的历史,虽然资产价格急剧波动的原因各不相同,但投资者的情绪波动却始终伴随其中;市场主体情绪波动是不可忽视的、对市场交易与价格波动产生影响的重要因素。本文是通过心理学实验,尝试在较纯净的实验市场中,控制与剔除其它因素的影响,探求在资产价格接近顶部与接近底部的情形下,交易主体情绪与交易行为之间的规律性关系。实验结果发现,在资产价格接近顶部的情形下,情绪波动与资产价格主要由基本面的变化决定,并且不同情绪的变化则会影响到交易主体对资产的买卖行为,这可能会加剧资产价格的波动。而在资产价格接近底部的情形下,投资者对资产的买卖行为更多地受到基本面信息变化的影响。实验结果发现了两种极端市场情部下,交易行为中“非理性”与“过分理性”的不对称。在国内外文献中,本文是首次将交易者情绪引入资产价格波动的研究。该研究对行为资产定价理论提供直接的心理学依据。

证券分析师通过传递信息、降低分析信息的成本来增进整个市场的有效性。基于中国沪深上市公司样本的研究发现,分析师跟进与股权融资成本具有负相关关系,分析师作为信息中介能够对资本成本产生影响,这也印证了Easle和O’hara(2004)提出的信息是经典三因素模型外影响资本成本的另一重要因素的理论假说。对这一作用逻辑可能的解释在于,分析师跟进能够扩大投资者基础,进而降低融资资本成本,实证结果证实了Merton(1987)提出的投资者认知假说。

We document the changes in dynamic stochastic structure of the various industrial sectors of the Chinese A, B share markets and the Hong Kong share markets. We utilize a robustly estimated VECM-MV-GARCH model to test for possible co-integrating vectors between the market segmentations pre and post deregulation of the Chinese B share market. Our results suggest that before deregulation there is weak evidence of co-integration between the A and B share markets however, post deregulation the situation changes and the segments appear to be significantly co-integrated. MV-GARCH results suggest that the conditional correlations of market/sector shocks also increase significantly over the sample period.

This paper investigates whether seasonalities in daily stock returns are related to the trading behavior of individual and institutional investors. The change in the investor structure of B-share markets in Shanghai and Shenzhen after the abolition of ownership restrictions in 2001 provides a unique testing environment. We show that day-of-the-week effects are attenuated after the market entrance of Chinese individual investors, who had previously not been allowed to trade in B-shares. Our empirical results suggest that institutional rather than individual investors are a main driving force behind such anomalies. In addition, we find evidence of reduced index return autocorrelation and US spillover effects in the post-liberalization period.

We study whether firm name has an effect on firm valuation. Some Chinese firms listed on U.S. stock exchanges have the word "China" or "Chinese" included in their company names ("China-name stocks"), whereas others do not ("non-China-name stocks"). During the China stock market boom in 2007, we find that China-name stocks significantly outperform non-China-name stocks. This is not due to differences in firm characteristics, risk, or liquidity. We also find a significant increase in both abnormal returns and trading volumes of existing China-name stocks to the listing events of new Chinese initial public offerings. This "China-name effect" is largely consistent with the hypothesis that optimistic investor sentiment during the China stock market boom drives up China-name stocks more than non-China-name stocks.

As the launch of the China’s first stock index futures (SIF) approaches with no exact date for its eventual introduction. The Chinese stock market has increased dramatically due to this expectation recently, especially the futures contracts related stocks have raised significantly which are good examples of this influence. As the stock index futures is a new financial product, Chinese investors cannot help wondering whether the launch of the stock index future will have a positive or negative impact upon the underlying stock market. On the other hand, the new instruments which, will be followed by the introduction of other derivatives, will require broker-dealers to upgrade their systems and invest in new technology. Therefore, it has become pertinent to investigate the opportunities and challenges this eagerly awaited derivative instrument has to offer to fund managers in the booming Chinese economy.

我国基金市场的飞速发展,证券投资基金已经成为股票市场中一支举足轻重的投资力量,它们的投资决策选择足以对整个股票市场造成轩辕大波,因此对基金的资产配置决策研究有助于了解实务界的证券投资理念和股票市场的变化原因,对配置决策与基金收益的研究更可以为投资者提供有益的投资参考。本文对资金配置的最基本问题——分散还是集中——展开实证分析,与存量研究不同,本文着眼于基金对新流入资金的配置决策研究,并提出基于基金实际持股组合的能够同时有效处理股票型基金和混合型基金的五因素风格调整模型,从而进行分散化配置决策与基金边际决策收益的关系研究。面板回归结果发现,基金更倾向于把新流入资金加大原股票组合的持有比例,分散化倾向很低;因为管理能力、隐性成本和股票流动性的限制,分散化和集中化存在相互促进的关系;分散化配置决策在总体上能给基金带来额外收益,但是研究发现分散化的收益影响是凸型的,给基金带来最大收益的分散化范围在41只到63只股票之间。另外,本文的实证检验得到依据风格调整收益的选择基金标准:大家族、小净值、小盘股、高费率、羊群倾向低、交易低密度、持股50只左右。