Size and information revelation in securities trading

We examine differences in information content between order submission sizes and trade sizes by U.S. equity traders. Increasing (decreasing) order submission (trade) size is reflective of information. The result suggests that better-informed traders want to trade in a large size, but that they engage in stealth trading practices or break larger orders into smaller sizes in order to conceal information. While prior studies tend to narrowly focus on trade executions at the market-centre level, our findings indicate that order submission size varies significantly from trade size and that both sizes are informative about future prices, albeit in an inverse manner.     

离差交易的实证研究与探讨

离差策略是一种对冲交易策略，它是利用股指期权和一揽子股票期权（或部分成分股构成的ETF期权）之间的隐含相关系数，获悉市场成分股期权和股指期权波动率高低的相对关系，再在成分股期权和股指期权建立相反的头寸。离差交易策略选择暴露的风险因子就是隐含相关系数，离差交易使用的是对冲的平价跨式期权交易。选用2006年5月18日至2014年7月17日前复权的沪深300股指、上证50指数和上证180指数作为样本，进行实证检验。虽然结果显著性较强，但不排除存在模型不稳定性以及由于数据不充分造成对相关系数及波动率估计的偏误。同时，离差交易使用的是对冲的平价跨式期权交易，所以组合暴露较小的Delta风险。若离差交易涉及较大的资金量时，则需要用标的资产对组合进行动态Delta中性对冲。     

会计信息披露时机与内幕交易——基于年报首季报披露时差与异常超额交易量的实证研究

考虑到资金成本、市场的系统性风险和被监管的可能性,内幕交易者最可能利用两个相隔时间很短的定期报告进行内幕交易。因为这种交易模式最隐蔽,最安全。同时,因承担了高成本和高风险,内幕交易需要巨额的交易量才能获得超额收益。本文正是利用内幕交易的这些特征,找到了极好的研究样本（年报亏损下年首季报盈利且年报首季报先后公布的样本）和控制样本（年报亏损下年首季报盈利但年报首季报同时披露的样本或者年报亏损下年首季报仍然亏损且年报首季报先后公布的样本）,通过异常的超额交易量验证了内幕交易的存在。本文研究表明,在信息披露监管政策中,不仅要考虑信息披露的及时性和充分性,还应考虑信息披露过程是否为内幕交易提供了可乘之机。     

Return enhancement trading strategies for size based portfolios

Recent theoretical work suggests that definitions of market efficiency that allow for the possibility of time-varying risk-premia will generally lead to return sign predictability. Consistent with this theory, we show that a logit model based on the lagged value of the market risk premium is useful for successfully predicting the return sign for CRSP small decile portfolio returns, but not large ones. We additionally employ this model in market timing simulations of micro-cap mutual funds in which investment can actually be made. The results indicate that a market-timing strategy based on our return-sign forecasting model outperforms a buy-and-hold strategy for 13 of 14 micro-cap funds studied. On average, the buy-and-hold strategy produces an average compound return of 11.98% per annum versus an average of 16.60% for the market-timing strategy. Nevertheless, trading restrictions make the return-sign forecasting model more practical to employ by the micro-cap fund portfolio manager rather than the individual fund investor.

Institutional stakeholdings and better-informed traders at earnings announcements

Utama and Cready [Utama, S., Cready, W.M., 1997. Institutional ownership, differential predisclosure precision and trading volume at announcement dates. Journal of Accounting and Economics 24, 129–150] use total institutional ownership to proxy for the proportion of better-informed traders, an important determinant of trading around earnings announcements. We argue that institutions holding small stakes cannot justify the fixed cost of developing private predisclosure information. Also, institutions with large stakes generally do not trade around earnings announcements since they are dedicated investors or face regulations that make informed trading difficult. However, institutions holding medium stakes have incentives to develop private predisclosure information and trade on it; we show that their ownership is a finer proxy for the proportion of better-informed traders at earnings announcements.     

减排与增长:服务业如何实现绿色均衡发展?

服务业是中国经济转型和产业结构升级的重要抓手,在资源与环境"双重"约束日益趋紧的背景下,有必要研究服务业绿色发展问题。能否在减排成本最小的前提下提高服务业增长率,走出一条绿色发展路径?为此,文章创新性地将排放权交易市场引入服务业部门,采用方向性距离函数、非线性规划等实证研究方法测算2004-2012年中国服务业14个细分行业的绿色效率和碳排放影子价格。研究表明:中国服务业发展方式并非"绿色",服务业减排成本和碳排放量逐年增长,减排面临巨大的经济压力;在文章设计的排放权交易模型下,服务业细分行业能够形成一个统一的影子价格,从而实现一条绿色发展路径,该路径满足帕累托有效和投入产出技术有效;在均衡路径上,流通服务业应出售排放权,而其他减排成本较高的服务业购买排放权。     

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。     

碳排放、绿色全要素生产率和经济增长

通过把资本存量、就业人数、能耗、时间等变量纳入超越对数生产函数,将碳排放总量、能源强度等变量以及区域虚拟变量作为生产无效率函数的解释变量构建随机前沿模型进行实证分析。结果显示：碳排放增长会扩大技术无效率项并降低绿色全要素生产率;技术进步降低了能源强度却引至了更多的碳排放,符合杰文斯悖论;减排技术较高的地区对应较高绿色全要素生产率增长水平;绿色全要素生产率增速比传统全要素生产率增速更快。     

Accounting conservatism in a setting of Information Asymmetry between majority and minority shareholders

Following LaFond and Watts (2008), we examine the relation between information asymmetry (as measured by PIN, probability of information-based trading) and accounting conservatism but focus on a country – Taiwan – whose institutional background is different from that of the United States. Due to the disparate degree of conservatism across the world, the conclusions of LaFond & Watts (2008) might not be universally applicable. Our findings support, in general, the applicability of their conclusion to a Taiwan data set. We find, however, that the effect of PIN appears weaker when auditor tenure is taken into account, thus supplementing their conclusions.     

F-F三因子资产定价模型的扩展及其实证研究

针对中国证券市场的特征,本文引入会计指标市盈率、技术指标换手率,对标准F-F三因子模型进行了不同层面的改进。实证结果表明,标准F-F三因子定价模型基本能解释中证100样本股相应组合的周回报率,但效果不是很好;换手率高低对组合收益率的解释能力并不优于标准模型,但换手率与市盈率同时进入模型,却能有效提高周收益率的解释,是一个基本适合中国股市的资产定价模型。