AUTOMOTIVE RECALLS AND INFORMATIONAL EFFICIENCY

This study provides an empirical test of the informational efficiency of the stock market by exploring the stock price and volume patterns exhibited by Chrysler, Ford, and General Motors around the time of announcement of severe automotive recall campaigns. Because information concerning automotive recalls is released to the public via two distinct methods, which differ only with respect to the number of market participants notified of the recall campaigns, a differential performance analysis of stock returns and trading volume around both events provides evidence of the degree of informational aggregation in the stock market for three closely followed U.S. firms. The results of the study fail to support the definitional notion of informational efficiency with respect to the first public release date of severe recalls, as the vast majority of the stock market's response to recall announcements does not occur until the information is reported to all market participants. Further, tests of differential trading volume around the announcements suggest that some members of the financial community may be trading securities on the basis of the information contained in the first public announcement.     

Event study with imperfect competition and private information: earnings announcements revisited

Although prior research documents that prices respond to earnings announcements, only a little of the price variation is explained by these announcements. To further investigate the properties of the information environment around these announcements we use NYSE TAQ data and compute the maximum likelihood estimates (MLEs) of the primitive parameters of a Kyle (Econometrica 53(6):1315–1336, 1985) type model within and around earnings announcement windows. These include the precision of fundamentals given only public information, the precision of private signals, and the variance of uninformed liquidity trading (noise). We find that liquidity noise is higher while the precision of beliefs given only public information is lower within an earnings announcement window. The precision of private information is higher in an event window, consistent with greater information acquisition to try and interpret a public announcement. We also document that Kyle’s λ is higher in an event window, showing an overall increase in information asymmetry. Our overall findings suggest that the earnings announcement window is distinguished from the preceding and subsequent windows not by being a period with more public information but as a period with different public information.     

Informed trading in public debt markets

This study examines the occurrence of informed trading in public debt issued by companies in the United States. I find that earnings surprises are positively associated with bond price changes prior to the release of financial report data to the public, for firms with non‐investment‐grade ratings. Additionally, I find that the effect appears to be driven by firms with publicly traded equity. Evidence further indicates an increase in trading activity during the time window between report period end date and filing date, for firms with larger earnings surprises.     

Economic News and the Impact of Trading on Bond Prices

This paper studies the impact of trading on government bond prices surrounding the release of macroeconomic news. The results show a significant increase in the informational role of trading following economic announcements, which suggests the release of public information increases the level of information asymmetry in the government bond market. The informational role of trading is greater after announcements with a larger initial price impact, and the relation is associated with the surprise component of the announcement and the precision of the public information. The results provide evidence that government bond order flow reveals fundamental information about riskless rates.     

Is There Private Information in the FX Market? The Tokyo Experiment

We provide evidence of private information in the foreign exchange market. The evidence comes from the introduction of trading in Tokyo over the lunch hour. Lunch-return variance doubles with the introduction of trading, which cannot be due to public information since the flow of public information did not change with the trading rules. We then exploit microstructure theory to discriminate between the two alternatives: private information and mispricing. Four key results support the predictions of private-information models. Three of these involve changes in the intraday volatility U-shape. The fourth is that opening trade causes mispricing's share in variance to fall.     

Insider trading patterns

We revisit the information content of stock trading by corporate insiders with an expectation that opportunistic insiders will spread their trades over longer periods of time when they have a longer-lived informational advantage, and trade in a short window of time when their advantage is fleeting. Controlling for the duration of insiders' trading strategies, we find robust new evidence that both insiders' sales and purchases predict abnormal stock returns. In addition, we provide evidence that insiders attempt to preserve their informational advantages and increase their trading profits by disclosing their trades after the market has closed. When insiders report their trades after business hours, they are more likely to engage in longer series of trades, they trade more shares overall, and their trades are associated with larger abnormal returns. Finally, we show how accounting for these trading patterns sharpens screens for corporate insiders who trade on infor- mation.     

Public Information Arrival

We develop a measure of public information flow to financial markets and use it to document the patterns of information arrival, with an emphasis on the intraday flows. The measure is the number of news releases by Reuter's News Service per unit of time. We find that public information arrival is nonconstant, displaying seasonalities and distinct intraday patterns. Next we relate our measure of public information to aggregate measures of intraday market activity. Our results suggest a positive, moderate relationship between public information and trading volume, but an insignificant relationship with price volatility.     

Information transfer,microstmctures and intraday price return spikes

Previous research has identified overnight public information as the cause of higher opening returns and mean reversion in security markets. This paper tests this hypothesis by using an intervention and transfer function time series model to filter out the dynamic effects of an overnight information set on the opening, and subsequent, intraday AOI stock and SPI futures intraday price returns. A further research objective was to analyse the process by which information is transferred into prices and whether there is a differential impact across stock and futures markets. It was determined that the information contained in the overnight US stock market had: (i) a differential impact on the Australian stock and futures market, and (ii) after filtering out the impact of overnight information, a significant reversal tendency remained in both markets after opening. Further analysis supported the conclusion that price spikes at opening were not wholly related to overnight information. Other possible explanations, such as different trading mechanisms, did not provide a satisfactory explanation. Overall, it appears that the uncertainty participants face at the beginning of a trading session may induce a number of subtle market reactions (both rational and irrational), in markets with different microstmctures and trading clientele.     

Price Formation and Liquidity in the U.S. Treasury Market: The Response to Public Information

The arrival of public information in the U.S. Treasury market sets off a two-stage adjustment process for prices, trading volume, and bid-ask spreads. In a brief first stage, the release of a major macroeconomic announcement induces a sharp and nearly instantaneous price change with a reduction in trading volume, demonstrating that price reactions to public information do not require trading. The spread widens dramatically at announcement, evidently driven by inventory control concerns. In a prolonged second stage, trading volume surges, price volatility persists, and spreads remain moderately wide as investors trade to reconcile residual differences in their private views.     

交易透明度对证券场外交易信息效率的影响

黑池交易系统（Dark Pools）是美国近年发展较快的非公开交易平台, 其信息透明度较低,可提供匿名交易的服务,并由此实现信息的非公开传递。通过扩展后验信念收敛速率的模型来描述不同交易透明度下场外市场的信息显示速率, 发现私人信息与公共信息共存有利于信息更快地显示,因而私人信息渠道与公共信息渠道共存有利于提升信息效率,由此解释了非公开交易平台的价值,也为我国场外市场的分层发展提供可行建议.     

Differential informational and dynamic behavior of stock trading volume

This article develops a multiperiod rational expectations modelof stock trading in which investors have differential informationconcerning the underlying value of the stock. Investors tradecompetitively in the stock market based on their private informationand the information revealed by the market-clearing prices,as well as other public news. We examine how trading volumeis related to the information flow in the market and how investors'strading reveals their private information.     

Informed trading on debt covenant violations: the long and short of it

We examine whether disclosure of complex information events reduces information asymmetry by investigating the long‐ and short‐term impact of firms' disclosure of debt covenant violations on the probability of informed trading. We argue debt covenant violation disclosures provide informed agents with a long window of opportunity to trade on their private information largely due to the uncertainty arising from the debt renegotiation process. We find the probability of informed trading is greater after the disclosure, particularly when the violation outcomes are unresolved or where there is concern about possible future violations.     

The Effects of Public Information with Asymmetrically Informed Short‐Horizon Investors

This paper analyzes the effects of public information in a perfect competition trading model populated by asymmetrically informed short‐horizon investors with different levels of private information precision. We first show that information asymmetry reduces the amount of private information revealed by price in equilibrium (i.e., price informativeness) and can lead to multiple linear equilibria. We then demonstrate that the presence of both information asymmetry and short horizons provides a channel through which public information influences price informativeness and equilibrium uniqueness. We identify conditions under which public information increases or decreases price informativeness, and when multiple equilibria may arise. Our analysis shows that public information not only directly endows prices with more (public) information, it can also have an important indirect effect on the degree to which prices reveal private information.     

Price Discovery in Initial Public Offerings and the Role of the Lead Underwriter

We examine the price discovery process of initial public offerings (IPOs) using a unique dataset. The first quote entered by the lead underwriter in the five-minute preopening window explains a large proportion of initial returns even for hot IPOs. Significant learning and price discovery continues to take place during these five minutes with hundreds of quotes being entered. The lead underwriter observes the quoting behavior of other market makers, particularly the wholesalers, and accordingly revises his own quotes. There is a strong positive relationship between initial returns and the time of day when trading starts in an IPO.     

The type of corporate announcements and its implication on trading behaviour

I report the empirical evidence to show how firms’ expected and unexpected announcements affect investors’ trading behaviour. I find that trading volume decreases before expected announcements, either scheduled or unscheduled, consistent with models that predict that discretionary liquidity traders may postpone their trading until after an anticipated news release. I also find that the magnitude of pre-announcement trading reactions is negatively associated with the level of pre-disclosure information asymmetry. I further find that trading volume is boosted before unexpected announcements, and the relation between the magnitude of pre-announcement trading reactions and the pre-disclosure information asymmetry is weakly significant or insignificant.     

Arbitrage Chains

A privately informed trader will engage in costly arbitrage, that is, trade on his knowledge that the price of an asset is different from the fundamental value if: (1) his order does not move the price immediately to reflect the information; and (2) he can hold the asset until the date when the information is reflected in the price. We study a general equilibrium model in which all agents optimize. In each period, there may be a trader with a limited horizon who has private information about a distant event. Whether he acts on his information, and whether subsequent informed traders act, is shown to depend on the possibility of a sequence or chain of future informed traders spanning the event date. An arbitrageur who receives good news will buy only if it is likely that, at the end of his trading horizon, a subsequent arbitrageur's buying will have pushed up the expected price. We show that limited trading horizons result in inefficient prices, because informed traders do not act on their information until the event date is sufficiently close. We also show that limited horizons can arise because of the cost-carry associated with holding an arbitrage portfolio over an extended period of time.     

Exchange Rates and FOMC Days

Federal Open Market Committee (FOMC) meeting days provide a natural laboratory for exploring the effects of policy uncertainty and learning on exchange rate determination. A reasonable hypothesis is that the meeting outcomes are price-relevant public information associated with a switch to an "informed-trading state." Evidence is provided by intradaily exchange rates for 10 FOMC meetings. A particularly interesting finding is that the informed-trading regime tends to emerge during the time that the FOMC meets. An extensive search of public news indicates that the informed trading cannot be explained as the response to public information.     

Volatility,information, and double versus walrasian auction pricing in US and Japanese futures markets

This study empirically examines volatility in US and Japanese commodity futures markets. The US futures market, COMEX, is double auction with continuous trading, whereas the Japanese futures market, TOCOM, was Walrasian with discrete trading until April 1991. We find intraday volatility for gold futures contracts to be significantly higher on COMEX than TOCOM throughout the sample period and is attributable to differences in information flows and market micro-structures. Evidence is also provided that exchange volume conveys information both within and across markets, which is consistent with the French and Roll, 1986 (French, K.R., Roll, R., 1986. Stock return variances: The arrival of information and the reaction of traders. Journal of Financial Economics 17, 5–26) private-information based rational trading model. Finally, daily variance and autocorrelation estimates within COMEX are consistent with the extant literature on equity markets.     

The S&P500 index effect reconsidered: Evidence from overnight and intraday stock price performance and volume

This study focuses on S&P500 inclusions and deletions, examining the impact of potential overnight price adjustment after the announcement of an S&P500 index change. We find evidence of a significant overnight price change that diminishes the returns available to speculators although there are still profits available from the first day after announcement until a few days after the actual event. More importantly, observing the tick-by-tick stock price performance and volume effects on the key days during the event window for the first time, we find evidence of consistent trading patterns during trading hours. A separate analysis of NASDAQ and NYSE listed stocks allows for a detailed examination of the price and volume effect at an intra-day level. We find that index funds appear to cluster their rebalancing activities near to and after the close on the event date, suggesting that they are more concerned with tracking error than profit.