外汇期权信息含量与在岸离岸市场效率

央行在“8·11”汇改后放松了汇率中间价的管理,采用更为市场化的方式形成中间价,这种变化对于人民币汇率衍生品市场的影响尚属未知。为此,本文从人民币期权组合的Black-Scholes隐含波动率历史报价数据中提取出在岸、离岸市场人民币期权的无模型隐含波动率和风险中性偏度,在将样本划分为汇改前后三个不同的阶段的基础上,检验了期权隐含指标对未来汇率分布的预测能力。实证结果表明,在“8·11”汇改之后,随着人民币中间价形成机制变得更加市场化,期权价格中包含了越来越多关于未来汇率分布的信息,在岸和离岸期权市场的信息效率都有显著提高,意味着人民币中间价形成机制的市场化能显著提升我国金融市场效率。因此,在兼顾金融安全的角度上,稳步促进人民币中间价形成机制市场化进程将有利于我国金融市场效率的提高。     

市场效率:股指期权、股指期货与股指的关系——来自香港恒生指数市场的证据

使用2007年7月3日到2009年3月31日期间日度数据,从定价效率和信息效率两个方面讨论并检验了香港恒指衍生品市场的市场效率。研究发现:(1)信息效率检验显示恒指现货、恒指期货市场为弱式有效,恒指期权市场没有呈现出弱式有效的市场特征;(2)定价效率检验显示香港恒指期货、期权市场都是具有定价效率的衍生品市场;(3)恒生指数和其衍生品市场之间的领先——滞后关系符合成本交易假设,恒指期权收益领先恒指期货收益,恒指期货收益领先恒指现货收益,恒指期货和恒指期权市场在价格发现功能中占据主导地位;(4)恒指期权市场的存在,完善了套利机制,增强了现货市场和期货市场的流动性。这个结论为中国持续连贯地发展股指衍生品市场提供了坚实有力的证据,因此笔者建议在沪深300股指期货平稳运行之后,中国应该适时推出同一标的指数的股指期权产品,形成股指期货和股指期权市场并行发展的股指衍生品市场格局。     

期货市场的交易量与价格波动

本文检验了美国期货市场WTI原油、S＆P500指数和10年期国债品种的日内、日间价格波动与日内交易量、隔日交易量之间的关系,发现预期的日内和隔日交易量都有平抑期货市场价格波动的作用,非预期的隔日交易量与期货价格波动之间有正相关关系,非预期的目内交易量对价格波动的影响不显著。从信息对称性的角度分析,预期的交易量中含有更多信息,能抑制期货价格的偏离;非预期的交易量主要由信息反馈者提供,他们往往对期货价格的变动做出过度反应,从而加剧价格波动。     

2008全球期货和期权市场扫描

经历了数年飞速发展后,2008年全球期货和期权交易量保持增长,但同比仅上升13．7％,高速增长的势头出现拐点。同时,信用危机严重损害了核心金融市场的流动性。     

中国A股市场大交易量与收益率关系的研究

利用技术分析制定股票投资策略是投资者主要采用的方法之一,而对交易量与收益率两者之间关系的研究又是技术分析的基础。我们认为,大交易量能更好地预测未来股票的收益。本文通过对中国A股市场代表不同规模股票的指数实证研究发现,不同指数在大交易量形成后的检验期里反应是不同的。代表大盘股的指数存在明显的"大交易量溢价效应";而代表小盘股的指数几乎不存在这种效应。我们还进一步的发现,这种"大交易量溢价效应"只发生在指数上涨了10%-20%的情况下。最后,我们给出了相关的投资策略。     

产品市场势力与股票市场交易量:基于异质信念的解释

基于2001年至2009年A股市场上市公司的数据,本文从异质信念的角度检验了产品市场势力与股票市场交易量之间的关系。结果发现产品市场势力的提高能显著促进个股的交易,这与Peress(2010)的研究一致。不同的是,我们发现产品市场势力提高能通过增加投资者的异质信念水平促进交易,这和本文的预期一致。另外,我们的结果还表明产品市场势力与投资者单笔的交易量显著正相关。     

不完全信息下风险投资期权博弈分析

文章从两个方面对不完全信息下的风险投资价值作出估计,一方面基于实物期权法,另一方面基于期权博弈法。根据估计的风险投资项目价值,对风险投资决策作出建议。     

人民币外汇期权市场的阶段性发展

人民币外汇期权于2014年获得阶段性的成绩,在期权交易量、产品种类及专业化程度、市场参与度等各方面部获得了显著提升。文章从政策、市场环境及市场参与者等方面分析了促进人民币期权市场发展的基础环境,分析了当前市场运行的特点,并提出未来市场进一步发展的建议。     

财务报表信息含量的分析--来自内蒙古地区上市公司的经验证据

本文以内蒙古地区的上市公司为样本,从交易量反应和财务指标与股价的相关性两方面对财务报表公告信息的有用性进行了实证检验,结果证明了我国上市公司的财务报表具有一定的信息含量,在一定程度上影响了财务报表信息使用者的决策.     

业绩快报的信息含量:经验证据与政策含义

业绩快报是上市公司2004年报披露中的一项制度创新。本文旨在研究业绩快报是否具有信息含量,以及业绩快报的披露是否会减少盈利公告的有用性。我们选取了2005年1月至4月间披露的70份2004年度业绩快报作为样本进行了实证研究。研究结果表明:业绩快报的披露提高了会计信息质量;业绩快报具有显著信息含量;业绩快报的披露并没有减少盈利公告的信息含量,是盈利公告的一种有益补充形式,值得提倡和推广。     

Daily Stock Trading by Investor Type and Information Asymmetry: Evidence from the Korean Market

We examine the influence of trading by heterogeneous investors on information asymmetry in the Korean stock market, which includes domestic and foreign institutional investors and individual investors. In particular, we examine the relationship between the daily trading volume and the level of information asymmetry reflected in the stock price. The results reveal that high-volume daily trading by domestic institutional and individual investors increases the degree of information asymmetry in the short term, but is more evident for individual investors. Foreign institutional investors tend to mitigate the information asymmetry. Finally, our findings are robust to an alternative measure of investor trading.     

Return Volatility,Trading Imbalance and the Information Content of Volume

In this paper, we examine the relationship between volume and return volatility using the transaction data. We introduce transaction and volume imbalance measures to capture the information content of trades. These two information measures are shown to have a strong explanatory power for return volatility and contain incremental information about the asset values over and above that conveyed by the size and frequency of trades. Also, return volatility is significantly correlated with the percentage of trading volume taking place at NYSE. This result suggests that NYSE trades are more informative and contribute more to price discovery. There is evidence that price discovery concentrates in more heavily traded stocks, particularly the Dow Jones Stocks. Finally, return volatility is found to be persistent at the intraday level. The persistence level is higher for less frequently traded stocks. Return volatility also exhibits temporal variations. In particular, return volatility is significantly higher in the opening half-hour for less frequently traded stocks. Thus, stocks with different frequencies of trades may follow different volatility processes.     

投资者分歧、异常交易量和股票横截面收益率预测——基于中国股票市场的经验证据

本文定义月度异常交易量为本月与上个月交易金额的比值,发现中国市场月度收益率与滞后一个月的异常交易量显著负相关。在控制了公司规模、账面市值比、流动性以及动量效应等指标后仍然具有显著的解释作用。进一步研究表明,在出现高异常交易量后的12个月内,换手率和特质性波动率都有大幅上升。本文认为,交易量上升代表着市场分歧程度和受关注程度的增加,在卖空约束下会使得股票价值高估,从而造成未来收益率下降。     

Tax-Induced Trading of Equity Securities: Evidence from the ADR Market

We examine ex‐dividend date trading of American Depositary Receipts (ADRs) using a sample of 1,043 dividends over the period 1988 to 1995. ADR dividends are often subject to foreign withholding taxes, creating incentives for certain investors to avoid the distribution. ADRs exhibit negative abnormal ex‐dividend day returns, and their prices behave consistently with their related withholding taxes. Abnormal trading volume for taxable issues exceeds 130 percent and 300 percent of normal volume on the cum‐ and ex‐dates, respectively. Abnormal volume is an increasing function of foreign withholding tax rates and decreasing function of transactions costs. This abnormal ex‐date trading activity is consistent with tax‐motivated trading.     

A Note on the Information Content of Relocating Corporate Domicile: A Trading Volume Approach

Overseas location of corporate domicile is not new for Hong Kong. Before the eighties, some companies operating in Hong Kong, principally shipping companies and financial institutions, registered overseas for tax purposes. Since 1989 there has been a rapid increase in the number of companies deciding to relocate, including industrial companies. This study examinies the association between sharemarket trading and the relocation announcement. The results indicate that unusually large trading volumes are observed immediately after the announcement day.     

Trading on Private Information: Evidence from Members of Congress

I examine the stock trades of members of Congress and find that over 2004–2010 the buy‐minus‐sell portfolios of powerful Republicans have the highest abnormal returns, exceeding 35% on an annual basis under a one‐week holding period. Among powerful Republicans, the abnormal returns are mostly concentrated in the portfolios of those with less trading experience. I also find that the positive abnormal returns disappear after the Stop Trading on Congressional Knowledge (STOCK) Act was passed in 2012. My results imply that the STOCK Act affected politicians' incentives to trade on private information, which they acquired through their power and party membership.     

Information of Unusual Trading Volume

This article investigates the information content of stock unusual trading volume from the aspect of firm fundamental information revealed by both earnings formal announcements and preannouncements. By using the stock market data of China from the second quarter of 2003 to the end of 2015, this article provides evidence that, in general, stocks that experience unusually low trading volume over the week prior to earnings announcements have more unfavorable earnings surprises. However, because of the feature of mandatory pre-disclosure policy in China, this article further finds that the relation between unusually low trading volume and unfavorable earnings surprises only exists in the stocks without earnings preannouncements, because fundamental information is incorporated in the stock prices timely around preannouncements date. In addition, unusually low trading volume signals negative fundamental changes revealed by preannouncements, and this effect is more pronounced among stocks with higher short-selling constraints, but unusually high trading volume is value-irrelevant.     

卖空者与内幕交易——来自中国证券市场的证据

本文研究上市公司内部人减持、年报、诉讼、分析师评级、停复牌以及高送转等重大公告前后卖空交易行为的变化,系统考察卖空者是否参与内幕交易以及何种因素影响卖空者参与内幕交易,发现卖空率较高的股票具有较低的未来收益,表明卖空者拥有信息优势,属知情交易者;卖空者拥有非常精确的择时交易能力,在重大利空公告前显著增加卖空量,而在利好公告前则显著减少卖空头寸,表明卖空者作为知情交易者的信息优势源自内幕消息;公司内、外部投资者的信息不对称程度越低或公司所在地的法治水平越高,卖空者参与内幕交易的行为就越少。因此,监管机构应密切关注公司重大消息发布前后卖空量的异常变动,同时,完善信息披露规则、健全证券分析师制度并强化法律法规的执行力度,才能有效防范卖空者参与内幕交易。     

Trading Better Versus Making More: Evidence from an Emerging Market

Using transaction data from Egypt, we examined the controversy over which investor—domestic or foreign—has superior trading performance in emerging markets. We account for informational and behavioral differences across investors by classifying them by origin and type and comparing their performance in trade execution versus profitability. Domestic institutions execute trades at the best prices with the greatest advantage against foreign institutions. This advantage is reduced when foreign institutions focus on large firms and trades. Profitability analysis revealed, however, that domestic investors accrue significant losses against foreign investors, suggesting that trading better does not necessarily translate into making more money.     

Market Efficiency, Thin Trading and Non-linear Behaviour: Evidence from an Emerging Market

Emerging markets efficiency has been widely investigated, with mixed results. However such evidence is only reliable if the methodology adopted accounts for the institutional features of the market. Unlike previous studies this paper corrects for thin trading and incorporates possible non-linear behaviour and regulatory changes. Using Istanbul Stock Exchange data we show that in its early years the exchange was characterised by non-linear behaviour and inefficient pricing. However, regulatory changes encouraged participation, improved information quality and led to prices impounding information more rapidly, suggesting markets become efficient with high trading volume, reliable information and an appropriate institutional framework.