管理者交易的市场择时能力对市场流动性的影响

利用国泰安数据服务中心数据,采用事件研究法,考察中国上市公司中管理者买入交易和卖出交易对我国股票市场流动性的影响,结果显示:管理者买入后的市场流动性减弱,归因于管理者与其他市场参与者之间的信息不对称;管理者卖出降低管理者的股权,提高市场流动性,信息不对称减弱。管理者在市场交易比较活跃的日期交易,可能是因为在高的市场交易量下能隐藏管理者的私人信息。     

The societal benefit of a financial transaction tax

We provide a novel justification for a financial transaction tax for economies where agents face stochastic consumption opportunities. A financial transaction tax makes it more costly for agents to readjust their portfolios of liquid and illiquid assets in response to liquidity shocks, which increase both the demand for and the price of liquid assets. The higher price improves liquidity insurance and welfare for other market participants. We calibrate the model to U.S. data and find that the optimal financial transaction tax is 1.6% and that it reduces the volume of financial trading by 17%.     

Rolling settlement and market liquidity

This paper investigates the impact on UK stock and option markets of the change from an account based settlement system to a rolling settlement procedure. Such a change increases the transaction costs of short-term margin traders, and is likely to impact on the liquidity of the underlying market, as well as trading in the options market. Evidence is presented that the settlement procedure does impact on the liquidity of the market. Further, we find that rolling settlement increased market liquidity, consistent with the exit of margin traders as a result of the increase in short selling costs. Associated with this increase in liquidity is a significant reduction in nonoptionable stock trading volume, implying that margin trading may have been more prevalent in stocks without options. Finally, it is shown that while trading in stock options increased, the volatilities implied from call and put option prices indicate that put options have become relatively more expensive. This reflects the change in demand induced by the new settlement procedure, especially in terms of the increase in short selling costs.     

#br# 融资融券加大了沪深股市波动吗*

融资融券设计初衷是通过融资加强市场流动性和通过融券提供投资者规避价格下跌风险的金融工具，改善由供求关系严重失衡导致市场巨幅震荡的局面，实现资本市场长期稳定的目标。实际操作中，融资融券疏通货币市场和资本市场间的资金流动，撬动巨额资金涌入股市；融资规模扩张过快而融券做空力量薄弱，业务结构发展严重失衡，导致两融业务具有“小冲击、大波动”的金融加速效应，放大了外部冲击引起股价上涨和下跌的幅度。协整回归分析表明，两融业务规模的扩张和收缩对上证指数涨跌具有显著的同向影响。TGARCH事件模型结果进一步证实融资融券从稳定股价到加剧波动的功能变化。随着标的股票扩容和业务常规化，两融业务导致股市投机过度，加剧了沪深两市的资产价格异动，没有达到平抑波动的设计预期。     

融券制度与内部人寻租——来自准自然实验的经验证据

内部人寻租一直以来是理论与实务界关心的重点,如何有效抑制内部人寻租行为是资本市场的重大课题。本文以内部人交易度量内部人寻租,分析了融券制度对内部人寻租的影响。研究发现:(1)融券制度对内部人寻租有显著抑制作用,并且融券规模越大,内部人寻租越少。(2)相比于国有企业,非国有企业当中融券制度对内部人寻租的抑制作用更加明显。本文还将内部人交易分方向进行回归,结果显示融券制度对内部人寻租的抑制作用主要体现在卖出方向上。本文进一步分析了融券制度影响内部人寻租的路径,发现“竞争效应”和“信息效应”是融券制度影响内部人寻租的两条重要路径。本文考虑了竞争性解释——分析师关注的作用,发现分析师关注并不能影响本文结论的正确性;本文还利用反面事实推断、倾向得分匹配、反向因果检验等方法,确保实证结论的稳健性。本文的研究结果,丰富了内部人寻租的特征及影响因素研究,有利于市场监管部门加强对内部人寻租行为的控制;扩充了有关融券制度的文献,为卖空制度的推行及完善提供理论依据。     

资产专用性与交易成本节约——论企业是信用的载体

企业的功能不仅在于节约要素(中间品)交易成本,是要素的"间接定价装置",还在于节约最终产品交易成本.信息不对称的产品市场上,企业在交易中"制造"了一个重复博弈机制,这使其更关心长远利益.它用自身专用性资产--从价值和数量两个维度--来作为其产品是合格品的担保.专用性资产单位价值越大,数量越多,企业越有谋求长远利益、放弃短期机会主义行为的激励.市场上理性的买方考虑到这一点,总是认为效益越好、规模越大的企业越有可能提供合格品.企业是信用的载体,它一定程度上避免了产品市场由于信息不对称所引致的逆向选择,从而节约最终产品交易成本.我们的分析补充和完善了企业的交易成本理论.     

Asymmetric Information and Adverse Selection in Mauritian Slave Auctions

Information asymmetry is a necessary prerequisite for testing adverse selection. This paper applies this sequence of tests to Mauritian slave auctions. The theory of dynamic auctions with private and common values suggests that when an informed participant is known to be active, uninformed bidders will be more aggressive and the selling price will be higher. We conjecture that observable family links between buyer and seller entailed superior information and find a strong price premium when a related buyer purchased a slave, indicative of information asymmetry. We then test for adverse selection using sale motivation. Our results indicate large discounts on voluntary as compared to involuntary sales. Consistent with adverse selection, the market anticipated that predominantly low-productivity slaves would be brought to the market in voluntary sales.     

电子商务平台上的信息不对称、交易成本与企业机制的运用

基于交易成本理论,将电子商务平台上交易的商品分为两类——物理属性标准的商品和物理属性不标准的商品,将商品信息分为两类——物理描述信息和价格信息,研究了两类商品在两类信息上存在的信息不对称问题,并对比分析了在线交易中的市场机制和企业机制。指出:在市场机制下,信誉机制和搜索排名机制能有效缓解物理属性不标准的商品在物理描述信息上的信息不对称,但无法有效缓解物理属性标准的商品在价格信息上的信息不对称,解决物理属性标准的商品的价格信息不对称需要企业机制;在电子商务平台上部分地用企业机制代替市场机制可以减少交易成本。     

连续竞价市场的股权结构、非对称信息与流动性

本文采用分笔交易的高频数据研究了股权结构对指令驱动的连续竞价市场中流动性和非对称信息的影响。研究表明,机构投资者对股票流动性有正的影响,且机构投资者能够显著减少交易过程的信息不对称程度,从而降低流动性成本。以国有股权和法人股权为代表的公司内部人对股票流动性没有显著影响,但能够降低交易过程的信息不对称程度,对减少流动性成本有积极作用。上市公司持股比例越分散,信息不对称程度越低,流动性成本越低。     

The impact of the French financial transaction tax on HFT activities and market quality

Based on the first results, the French government estimates that the tax on cancelled orders, considered as tax on High Frequency Trading (HFT), generated no revenue in 2012. Our paper question the effectiveness of a modified cancelled order tax with no exemptions, all orders cancelled or modified within half-second time span are taxed. Our study has important implications for the regulation of HFT; we provide recommendations for regulators in relation to market rules which have yet to be introduced, using an artificial market framework. This paper addresses the question of whether this tax leads to a reduction in HFT activities and, as a result, to deterioration or amelioration of market quality. The evidence we provide should help market regulators to better understand the role played by HFT firms as liquidity suppliers. We show that HFT liquidity is short-lived. With the implementation of tax, decreased HFT activities do not have a statistically significant impact on market volatility and market liquidity measured by bid/ask spreads, but decrease dollar volumes as a liquidity measure. In addition, reduced HFT activities lead to less efficient markets as the deviation from fundamentals increases.     

投资者保护具有股票流动性效应——来自中国高频交易数据的经验证据

股权分置改革使得股票市场的资源配置功能得到了进一步的发挥,但大股东使用内幕交易等手段侵害中小股东利益的行为也会变得更加突出。在以往的研究中,人们仅关注了投资者保护对关联交易等"利益输送"行为的遏制作用,并没有关注投资者保护对内幕交易等"利益输送"行为的治理效应。事实上,加强投资者保护能够改善信息环境,减少内幕交易行为,这将导致股票流动性的上升和信息不对称程度的下降。这一结论对于股权分置改革后的中国证券市场具有尤为重要的指导意义。     

Price discovery and the effects of fragmentation on market quality: evidence from Cypriot cross-listed stocks

Using a novel high-frequency data set, we examine the contribution of Greek trading to the price discovery process of a pair of Cypriot blue-chip, cross-listed stocks during overlapping trading hours. Additionally, we investigate the effects of market fragmentation on the home market’s quality, as measured by microstructure-based liquidity measures. Contrary to earlier studies from other markets, our findings show that foreign stock exchanges can act as the leading contributors to price discovery and can concentrate the majority of trading activity and produce the lowest transaction costs. Our results also show that market fragmentation can lead to negative effects on market liquidity.     

Mechanism design with a liquidity constrained buyer: The 2×2 case

This paper studies the implications of buyers' liquidity constraints for the optimal selling strategy. The possibility that a buyer faces a binding liquidity constraint affects the seller's strategy in a nontrivial way. Specifically, when a seller has one unit of a good to sell to a buyer with a quasilinear utility function, the `no-haggling' result indicates that textbook monopoly pricing is optimal, absent liquidity constraints. Introducing a potentially binding liquidity constraint vitiates the no-haggling result, and can make it strictly beneficial for the seller to use nonlinear pricing, to commit to a declining price sequence, or to require the buyer to post a cash bond.     

Loss aversion and market crashes

This study proposes a rational expectation equilibrium model of stock market crashes with information asymmetry and loss averse speculators. We obtain a state-dependent linear optimal trading strategy, which makes the equilibrium price tractable. The model predicts nonlinear market depth and the result that small shocks to fundamentals (e.g., supply or informational shocks) can cause abrupt price movements. We demonstrate that short-sale constraints intensify asset price collapses relative to upward movements. The model also generates contagion between uncorrelated assets. These results are consistent with the main puzzling features observed during market crashes, namely abrupt and asymmetric price movements that are not driven by major news events but coupled with a spillover effect between unrelated markets.     

股票转让方式与极端收益风险——兼论新三板市场引入做市转让制度的经济后果

在极端收益风险形成机理的现有研究中,交易环节是其逻辑链条中缺失的一环;对于做市转让制度的实施效果,现有实证研究也普遍忽视了其对极端收益风险的影响.文章从交易环节入手,提出了一个解释极端收益风险形成机理的新假说,并以新三板市场引入做市转让制度为契机,实证考察了股票转让方式和极端收益风险之间的关系.研究发现:(1)与实施协议转让的股票相比,实施做市转让的股票极端收益风险显著较低,但更多的做市商并未带来显著更低的极端收益风险;(2)做市转让方式对股价暴涨风险的抑制作用在熊市中较强,对股价暴跌风险的抑制作用则在牛市中较强;(3)股票转让方式对极端收益风险的影响主要通过股票流动性路径起作用,而信息有效性路径会起作用主要是因为信息有效性和股票流动性之间的高相关性.使用处理效应模型来控制自选择偏差的影响,使用不同的极端收益风险度量指标,延长极端收益风险的计算窗口,均不改变上述实证结果.这表明,交易环节是影响极端收益风险的重要因素,做市转让方式的引入有助于降低新三板挂牌公司的极端收益风险.文章对于深入理解极端收益风险形成机理、改善新三板市场交易机制具有重要的意义.     

证券市场流动性、价格有效性与最优契约设计

本文研究市场流动性的作用。我们的分析表明,市场流动性通过影响交易者收集私人信息的激励而影响交易价格的有效性。进一步的分析表明,最优经理人报酬契约中应该包括股票价格这一变量。然而,当市场流动性不足,从而价格缺乏效率时,我们不应过多依赖价格变量。     

中国股市透明度提高对市场质量影响的实证分析

在股票市场的机制设计中,透明度即交易信息的披露程度是一个非常重要的方面。合理的透明度可以优化市场中相关信息的传递方式,并改善交易者的信息结构,有利于证券形成更加合理的价格,并进而提高市场的整体质量。2003年12月8日,中国股市信息披露规则发生变化,买卖盘揭示范围由3个最优报价扩大为5个,市场透明度显著提高。本文通过实证分析,较为全面地考察了透明度提高对深圳A股市场质量带来的影响。结果表明,透明度提高之后,市场的流动性明显上升,交易成本和市场波动性则显著下降,市场的信息传递效率也有所提高。这一切都表明,透明度的提高显著地改善了股票市场的整体质量。     

长期协议、价格指数和铁矿石定价研究

在长期协议市场和现货市场并存的条件下,当市场存在不确定性和信息不对称时,可以减小随机交易波动,这不仅有利于保持长期协议供给方的领先优势,还能有效降低市场的均衡价格。在我国进口铁矿石定价体系中,国外厂商铁矿石价格指数和中国铁矿石价格指数存在差异和共同点,因此,只有建立运行高效的铁矿石市场交易机制,我国才能获得国际铁矿石定价权。     

Transaction costs and informational cascades in financial markets

We study the effect of transaction costs (e.g., a trading fee or a transaction tax, like the Tobin tax) on the aggregation of private information in financial markets. We implement a financial market with sequential trading and transaction costs in the laboratory. According to theory, eventually all traders neglect their private information and abstain from trading (i.e., a no-trade informational cascade occurs). We find that, in the experiment, informational no-trade cascades occur when theory predicts they should (i.e., when the trade imbalance is sufficiently high). At the same time, the proportion of subjects irrationally trading against their private information is smaller than in a financial market without transaction costs. As a result, the overall efficiency of the market is not significantly affected by the presence of transaction costs.     

Effects of a price limit change on market stability at the intraday horizon in the Korean stock market

This article investigates the effects of a price limit change on the volatility of the Korean stock market’s (KRX) intraday stock price process. Based on the most recent transaction data from the KRX, which experienced a change in the price limit on 15 June 2015, we examine the change in realized variance after the price limit change to investigate the overall effects of the change on the intraday market volatility. We then analyse the effects in more detail by applying the discrete Fourier transform to the data set. We find evidence that the market becomes more volatile in the intraday horizon because of the increase in the amplitudes of the low-frequency components of the price processes after the price limit change. Therefore, liquidity providers are in a worse situation than they were prior to the change.