中国股市的惯性与反转效应研究

由于中国股市具有政策市的特征,本文在Hong和Stein(1999)模型的基础上,研究政策市背景下的中国股市的惯性与反转效应。我们的主要结果有:中国股市的反转效应相对于惯性效应要更明显一些,并且除了中期惯性与长期反转外,还存在一个超短期的惯性与短期的反转;同时,小公司股票相对大公司股票,惯性运动的趋势较弱,更容易发生反转,成交量大的股票相对于成交量小的股票,惯性运动的趋势较弱,更容易发生反转。最后通过实证分析,在中国股票市场对上述结果进行了检验,实证结果支持了我们的结论。     

Cross-sectional and time-series momentum returns and market dynamics: evidence from Japan

We test the behavioural theories of overconfidence and underreaction on cross-sectional (CS) and time-series (TS) momentum returns in the Japanese stock markets. Both CS and TS momentum returns are large and significant when the market continues in the same state and turns into losses when the market transitions to another state, consistent with the overconfidence but not the underreaction model. We find that TS conditional momentum returns exceed conditional CS momentum returns because of its active position since TS takes a net long (short) position following UP (DN) markets while CS is a zero-cost strategy irrespective of the market state. Finally, we find no relation between idiosyncratic volatility (IV) and momentum returns which is not supportive of either the overconfidence or underreaction model but implies that IV is not a significant limit to arbitrage in Japan.     

Price clustering and natural resistance points in the Dutch stock market: A natural experiment

This paper focuses on the tendency of stock prices to cluster at round numbers (like 10, 20, 30, etc. and to a lesser extent 5, 15, 25, etc.) and the related effect of round number price barriers (prices pass round numbers less frequently than other numbers). Two competing hypotheses are tested, using data from the Dutch stock market of the period 1990–2001. After 1 January 1999 stock prices were listed in euros, while guilders were still the currency of daily life until 2002. The aspiration level hypothesis predicts that round number effects in guilders will only slowly disappear. The odd price hypothesis predicts an abrupt change in round number effects after 1 January 1999. Generally, the results are consistent with the odd price hypothesis.     

股票市场量价关系分析——模型与实证

文章将行为金融学的分析方法引入到股票市场量价关系的研究中,在考虑市场参与者非理性行为———＂急于实现盈利＂同时＂不愿结算浮亏＂的前提下,首先通过供求分析,给出股票市场中的需求曲线与供给曲线,然后设定初始均衡,采用经济学中的比较静态分析方法,研究新信息到来时对初始均衡的影响,进而分析新信息的到来对成交量和价格的影响。模型的结论是＂成交量和成交价格的变动正相关＂、＂成交量和成交价格变动的绝对值正相关＂。使用计量经济学方法,基于中国A股市场的历史数据进行了实证检验,实证结果支持了模型的结论。通过进一步分析,文章最后还得出＂投资散户是股票市场的自动稳定器＂的结论。     

The New York Times and Wall Street Journal: Does Their Coverage of Earnings Announcements Cause “Stale” News to Become “New” News?

Recent research suggests that the stock market reacts to stale information if it is reported in the media because it is gives the impression of being “new” news. The objective of this study is to provide a unique test of this hypothesis using the time-series properties of quarterly earnings. It is well documented that seasonally differenced quarterly earnings for adjacent quarters are positively correlated. Therefore a component of current quarter earnings when reported is news that was known or predictable at the end of the prior quarter and thus is old news. We find for those firms that receive media coverage in the Wall Street Journal and The New York Times that the price reaction at the time of the announcement of current earnings to past quarter's seasonally differenced quarterly earnings is greater than those firms that do not receive media coverage. The result is consistent with stale earnings information being given the appearance of new information resulting in a further price reaction. This suggests that the stale information hypothesis and media coverage could be a partial explanation for post-earnings announcement drift.     

Pure numbers effects, market power, and tacit collusion in posted offer markets

This paper studies the effects of seller concentration and static market power on tacit collusion in extensively repeated laboratory posted-offer markets. Contrary to the implications of some earlier research, we find that tacit collusion does not become pervasive with extensive repetition. In a ‘strong no-power’ design persistently competitive outcomes are observed in markets with three or four sellers. Even duopolies are frequently competitive in this design. Unilateral market power raises prices, as predicted. However, static Nash predictions fail to organize outcomes across power treatments, because tacit collusion moves inversely with concentration. Excess capacity appears to explain observed tacit collusion levels.     

沪市“风格惯性”与“价格惯性”比较之实证研究

本文以1997～2003年沪市261支A股为样本．实证对比了＂风格惯性策略”和“价格惯性策略”的盈利性。结果表明．在我国股市上运用传统的价格惯性策略不能获利，而运用“风格惯性策略”，特别是买入过去6、9、12个月内收益最高的赢家组合．则能够获利。本文从行为金融学角度对这一现象作了理论分析。     

中国证券市场机构投资者的羊群行为研究

“羊群行为”是金融市场上一个令人困惑的现象,长期以来,投资者的羊群行为一直被认为是导致股票市场剧烈波动和引发市场系统风险的一个重要原因。以往对美国金融市场的研究表明,机构投资者在进行投资时存在典型的羊群效应,而研究表明我国证券市场中机构投资者的羊群行为更加典型。对这个问题作一个文献综述,并在此基础上进一步作理论研究和政策分析。     

上海股票市场动量效应研究——基于1995—2009年周收益率数据

利用1995年1月至2009年12月期间上海证券交易所所有A股股票的日收益率数据,以本周四到下周三为一个周期计算周收益率,采用重叠抽样方法,对上海股票市场的动量效应进行实证研究。结果表明:上海股票市场存在动量效应现象,但动量效应持续的期限要短于西方发达国家的股票市场;当形成期为1周、持有期为1~3周时,投资策略组合表现出显著的动量效应;当形成期大于1周、持有期超过3周时,投资策略组合开始出现收益反转现象;当持有期和形成期增大到12~26周时,投资策略组合又表现出不显著的动量效应。     

An experimental study of adaptive behavior in an oligopolistic market game

We consider an oligopolistic market game, in which the players are competing firms in the same market of a homogeneous consumption good. The consumer side is represented by a fixed demand function. The firms decide how much to produce of a perishable consumption good, and they decide upon a number of information signals to be sent into the population in order to attract customers. Due to the minimal information provided, the players do not have a well-specified model of their environment. Our main objective is to characterize the adaptive behavior of the players in such a situation.     

Entry,market turbulence and industry employment growth

This paper investigates the relationship between industrial dynamics in terms of firm entry, market turbulence and employment growth. Do entry of firms, the composition of industry dynamics (net entry) and market turbulence (entry and exit) influence industrial employment growth? This paper provides an empirical investigation, using unique data for 42 disaggregated Swedish industrial sectors during the period 1997–2001. It is hypothesised that the importance of entering firms, net entry and market turbulence may differ significantly across industries. A quantile regression method is used in order to detect industrial differences in the response to industrial employment growth. The empirical evidence shows that, on the one hand, firm entry and market turbulence have a positive effect on employment for fast growing industries and that the effect is larger for high growth industries. On the other hand, the composition of industry dynamics in terms of net entry rates has a more dispersed effect across all industries, even though the effect of net entry is larger for high growth industries.     

动量货币与传统货币指标的理论与经验分析

简单加总的货币指标早已受到理论和实践的挑战,而主流国家的各种改革方案均没有取得成功.其原因是西方学者偏重货币的资产功能,忽视到货币的交易功能,对货币的基本认识存在偏差.宇宙中不存在绝对静止的事物,货币的本性是运动.物理学的动量定理与经济学的交易方程式可以进行类比.笔者尝试建立了动量货币的指标,初步的经验分析结果富有启发意义.货币的重要性依赖于它的数量和速度.西方学者排斥货币的真实速度,宏观经济学的基本结构存在重大缺陷.     

The long run,market power and retail pricing

The paper examines the existence of market power in the respective pork and poultry (white meat) meat markets in Austria by means of the Johansen cointegration technique. The existence of market power in pork retail pricing is revealed. Poultry retail pricing is, however, found to be competitive. The result for pork is attributed to tradition and to the high pre-EU border protection rates. The paper also revealed the versatility of the Johansen cointegration technique as a tool capable of analysing both competitive and imperfect market situations. The paper recommends meat policy to be product specific rather than holistic.First version received: March 2000/Final version received: May 2003The research on which this article is based began in 1995 at the Federal Institute of Agricultural Economics, Vienna, with the support of the Austrian Federal Ministry of Agriculture and Forestry. An earlier version of the paper was presented at the 264^th NFJ Seminar, Alnarp, Sweden, 1996. The author is grateful to Karl M. Ortner for the data and to Robert M. Kunst, Karl M. Ortner, Martin Wagner and seminar participants for useful comments on earlier drafts.     

Regulation, market structure and service trade liberalization

In this paper, we develop a theoretical method to quantify the importance of regulation and market structure on the success of service trade liberalization. For this purpose, we incorporate a single imperfectly competitive service sector that can take on various market structures into a standard computational general equilibrium model. We apply our framework to analyze the impact of partial telecom liberalization in Tunisia. We show that if the regulatory environment guarantees competition, Tunisia's welfare can improve up to 0.65%. If a cartel is formed between the domestic incumbent and foreign entrant, however, Tunisia's welfare can drop up to 0.25%. Our results thus call for Tunisia among other developing countries to step up its pro-competitive regulatory reforms while liberalizing its telecom sector.     

城乡市场的分割和统一

建设新农村需要内生的持久的机制。城乡市场分割是我国新农村目标得以实现的根本性障碍，农民无法平等参与市场活动导致城乡收入差距不断扩大。因此，新农村建设的内生机制最为根本的是市场制度创新。创新的市场制度的基本功能能够有效地克服要素流动的障碍，并能在等价交换的基础上保障农民收益。     

Individual account investment options and portfolio choice: Behavioral lessons from 401(k) plans

This paper examines how the menu of investment options made available to workers in defined contribution plans influences portfolio choice. Using unique panel data of 401(k) plans in the U.S., we present three principle findings. First, we show that the share of investment options in a particular asset class (i.e., company stock, equities, fixed income, and balanced funds) has a significant effect on aggregate participant portfolio allocations across these asset classes. Second, we document that the vast majority of the new funds added to 401(k) plans are high-cost actively-managed equity funds, as opposed to lower-cost equity index funds. Third, because the average share of assets invested in low-cost equity index funds declines with an increase in the number of options, average portfolio expenses increase and average portfolio performance is thus depressed. All of these findings are obtained from a panel data set, enabling us to control for heterogeneity in the investment preferences of workers across firms and across time.     

Taxation and market work: is Scandinavia an outlier?

This paper argues that it is essential to explicitly consider how the government spends tax revenues when assessing the effects of tax rates on aggregate hours of market work. Different forms of government spending imply different elasticities of hours of work with regard to tax rates. I illustrate the empirical importance of this point by addressing the issue of hours worked and tax rates in three sets of economies: the US, Continental Europe and Scandinavia. While tax rates are highest in Scandinavia, hours worked in Scandinavia are significantly higher than they are in Continental Europe. I argue that differences in the form of government spending can potentially account for this pattern. An early version of the paper was presented at the 2003 conference in honor of Prescott being award the Nemmers Prize in Economics, held at the Federal Reserve Bank of Chicago. I have benefitted from the comments of numerous seminar participants, but would like to particularly thank Robert Lucas, Ed Prescott, and Nancy Stokey, as well as two anonymous referees, Stephen Parente and Anne Villamil for useful comments. I thank the NSF for financial support.     

Foreign investor trading and information asymmetry: evidence from a leading emerging market

This article examines the influence of foreign investor trading on information asymmetry in the Korean stock market, a representative emerging market characterized by a high level of information asymmetry between corporate insiders and outsiders, and among investors. We find a significantly positive relationship between foreign investor trading and the consequent bid–ask spread – the latter of which is considered as a proxy for the degree of information asymmetry – on both daily and weekly bases. Our results indicate that active foreign investor trading tends to exacerbate informational variation.     

Product market competition,incentives and fraudulent behavior

The present paper studies incentive provision in a model where a manager can affect the firm's stock price by exerting unobservable effort and through costly, deceptive signalling and investigates the role product market competition plays in shaping shareholders' trade-off between inducing effort and fraud.