Do foreigners facilitate information transmission in emerging markets?

Using the degree of accessibility of foreign investors to emerging stock markets, or investibility, as a proxy for the extent of foreign investments, we assess whether investibility has a significant influence on the diffusion of global market information across stocks in emerging markets. We show that greater investibility reduces price delay to global market information. We also find that returns of highly investible stocks lead those of noninvestible stocks because they incorporate global information more quickly. These results are consistent with the idea that financial liberalization in the form of greater investibility yields informationally more efficient stock prices in emerging markets.     

Is there price discovery in equity options?

We use tick-by-tick quote data for 39 liquid US stocks and options on them, and we focus on events when the two markets disagree about the stock price in the sense that the option-implied stock price obtained from the put-call parity relation is inconsistent with the actual stock price. Option market quotes adjust to eliminate the disagreement, while the stock market quotes behave normally, as if there were no disagreement. The disagreement events are typically precipitated by stock price movements and display signed option volume in the direction that tends to eliminate the disagreements. These results show that option price quotes do not contain economically significant information about future stock prices beyond what is already reflected in current stock prices, i.e., no economically significant price discovery occurs in the option market. We also find no option market price discovery using a much larger sample of disagreement events based on a weaker definition of a disagreement, which verifies that the findings for the primary sample are not due to unusual or unrepresentative market behavior during the put-call parity violations.     

行为模型新解及其实证检验

在以信息逐步扩散和投资者有限理性为主要假设的行为模型中,特定信息交易者和市场信息交易者的比例对股价行为有着重要影响：当特定信息交易者占多数时,个股收益更容易呈现正自相关;当市场信息交易者占多数时,个股收益更容易呈现负自相关。该模型可以解释成熟股市中存在基于总收益的动量效应,而中国股市中不存在基于总收益的动量效应,仅存在基于公司特定收益的动量效应;并解释了市场平均收益呈现负自相关等。另外,实证分析支持了传统的CAPM和APT定价模型中的带越小,动量效应越显著的结论。     

IPO限价发行与新股二级市场价格泡沫——论股票市场“弹簧效应”

本文通过对比2009年7月1日至2014年6月30日IPO市场化定价发行阶段与2014年7月1日至2018年6月30日IPO限价发行阶段共1950个IPO样本,发现IPO限价发行对于新股在二级市场股价表现具有“弹簧效应”:即抑制股票一级市场发行价格会造成新股在二级市场价格短期内超涨,限价发行新股的二级市场定价显著高于市场化定价发行新股的二级市场定价。限价发行引起的过高二级市场定价最终导致股票长期回报率低下。另外,创业板公司“弹簧效应”显著强于主板公司。这些实证结果都可以被本文提出的一级市场价格压抑造成二级市场非理性投资者上涨预期一致、盲目追涨的理论模型所解释。本文的研究指出抑制股票一级市场定价虽然形式上可以解决新股发行价过高问题,但是却造成二级市场更大的价格扭曲。这一发现为进一步完善我国IPO发行定价机制提供了依据。     

Intraday Price Change and Trading Volume Relations in the Stock and Stock Option Markets

This study investigates intraday relations between price changes and trading volume of options and stocks for a sample of firms whose options traded on the CBOE during the first quarter of 1986. After purging the price change series of the effects of bid/ask spreads, multivariate time-series analysis is used to estimate the lead/lag relation between the price changes in the option and stock markets. The results indicate that price changes in the stock market lead the option market by as much as fifteen minutes. The analysis of trading volume indicates that the stock market lead may be even longer.     

信息不对称、过度自信与股价变动

信息传导的非同步和投资者情绪变化是股票市场的两个典型特征,前者会引发投资者之间出现信息不对称问题,后者主要体现为投资者过度自信,两者共同作用影响股票价格变动。本文将信息不对称和投资者过度自信情绪置于同一个分析框架,建立两阶段动态序贯定价理论模型研究现实市场上信息传导过程中股价变动的内在机制。结果表明:(1)面临新信息的进入,投资者对股票收益预期的调整与均衡价格之间具有正相关关系;(2)面临有利消息时,过度自信投资者比例越大,股票的均衡价格越高,投资收益将越低;面临不利消息时则相反;(3)随着过度自信投资者比例以及过度自信程度升高,市场风险溢价将下降;(4)投资者群体在信息传导过程中出现分化,对股价变动形成异质信念,未获取信息和获取信息但未出现过度自信的投资者认为股价被高估,获取信息且出现过度自信的投资者认为价格被低估,促使更多的交易,引发市场成交量和股价变动;(5)过度自信投资者比例与过度自信程度提高均会对市场效率产生正向影响,而对市场深度具有负向效应。最后,基于理论结果对非对称性和持续性等典型的市场波动性特征进行解释。     

Price behavior of small-cap stocks and momentum: A study using principal component momentum

This study analyzes why the negative momentum effect appears in Asian (China, Japan, Korea) stock markets, contrary to the U.S. market. We use principal component momentum (PMOM), a newly devised momentum measure. The PMOM is constructed by extracting commonalities from traditional momentum measures using principal component analysis. The results show evidence of positive and negative momentum profits in the U.S. and Asian markets, respectively. Negative momentum profits in Asian markets are attributable to the strong performance reversal of small stocks in the loser portfolio. Conversely, the positive momentum profits of the U.S. market are driven by the performance continuity of small stocks in the winner portfolio. The PMOM strategy is significantly more advantageous than traditional momentum strategies, based on the economic and statistical perspectives of momentum profits. These results are robust to changes in empirical designs.     

Factor Models for Option Pricing

Options on stocks are priced using information on index options and viewing stocks in a factor model as indirectly holding index risk. The method is particularly suited to developing quotations on stock options when these markets are relatively illiquid and one has a liquid index options market to judge the index risk. The pricing strategy is illustrated on IBM and Sony options viewed as holding SPX and Nikkei risk respectively.     

Futures trading volume as a determinant of prices in different momentum phases

Recent studies contend that trading volume has predictive power for ex ante stock prices, particularly small stocks that do not react quickly to macroeconomic information. This study postulates that a significant amount of macro-information that flows on to stock markets is derived from derivative markets. We examine the impact of short-term futures trading volume and prices on cash stock prices using a case study of 15-min data from the Australian stock index futures market which reports actual trading volume. After applying vector error correction modelling (VECM), variance decomposition and impulse functions, we conclude that futures prices provide a short-term information lead to stock prices that dominates trading volume effects. We also observe asymmetric changes in the impact of trading volume between bull and bear price momentum phases and after large trading volume shocks. These results suggest that, in future, studies on trading volume should control for the cross-correlation impact from derivative prices and the differential impact of trading phases.     

Momentum and Foreign Investors: Evidence from the Korean Stock Market

Abstract:

We examine whether the price impact of foreign investors on the Korean stock market from December 2000 to February 2007 generated a momentum phenomenon. In our empirical results, foreigners seem to have exerted a significantly positive impact on prices in “up” markets (periods of positive stock returns), but have had little impact on prices in “down” markets (periods of negative returns). We document that the impact of foreigners’ trades is concentrated in large companies. Most importantly, when the market is in the up state, the returns of stocks of large companies that were positively affected by foreign investors in the previous six-month period continue to increase in the subsequent six-month period. As a result, the subsequent six-month return on a past “winner” stock portfolio is significantly higher than that on a past “loser” stock portfolio. This brings to mind a momentum phenomenon that has been reported not to exist in the Korean stock market.     

Momentum returns in Australian equities: The influences of size,risk, liquidity and return computation

The apparent predictability of stock prices, and the related profitability of investment strategies based on this, has generated a great deal of research. Since the late 1980s, momentum strategies have attracted considerable attention and have been found to be profitable in numerous markets. This paper investigates the returns to short-term and intermediate-horizon momentum strategies in the Australian equity market. We focus on ‘practical’ or ‘realistic’ investment strategies, and find that momentum is prevalent in the Australian market and that the returns are of greater magnitude than previously found in overseas markets. These momentum strategy returns are robust to risk adjustment and prevail over time. We also examine the interaction of momentum on size and liquidity variables and conclude that the observed profits to these investment strategies are not explained by size or liquidity differences among the stocks.     

Does Risk Seeking Drive Stock Prices? A Stochastic Dominance Analysis of Aggregate Investor Preferences and Beliefs

We use various stochastic dominance criteria that account for(local) risk seeking to analyze market portfolio efficiencyrelative to benchmark portfolios formed on market capitalization,book-to-market equity ratio and price momentum. Our resultssuggest that reverse S-shaped utility functions with risk aversionfor losses and risk seeking for gains can explain stock returns.The results are also consistent with a reverse S-shaped patternof subjective probability transformation. The low average yieldon big caps, growth stocks, and past losers may reflect investors’twin desire for downside protection in bear markets and upsidepotential in bull markets.     

INTERNATIONAL TRANSFER OF PRICING INFORMATION BETWEEN DUALLY LISTED STOCKS

International multiple listing offers a unique opportunity to study the efficiency of information transmission across national markets. The knowledge gained from observing a stock of the same company priced in multiple markets differs from what may be gained from observing relations across markets of aggregate price indices. We investigate five companies based in Israel whose stocks are listed on both the Tel Aviv Stock Exchange and NASDAQ. Our empirical tests of causality in price changes use the side-by-side Box-Jenkins ARIMA models and the Sims VAR model. Overall, the results show that price causality in dually listed stocks is unidirectional from the domestic market to the foreign market.     

投资者关注与市场反应——来自中国证券交易所交易公开信息的自然实验

涨停的股票能否被交易公开信息披露取决于收益率排名中的随机因素,与股票的基本面特征无关。本文利用这一机制设计自然实验检验了投资者关注对股价的影响。实证结果显示交易公开信息披露使股票受到投资者更多的关注,增加了小额资金的净流入,减少了大额资金的净流入和股价的短期收益率,抑制了股价短期波动率,同时降低了股价在长期发生反转的可能性。频繁登上交易公开信息的知名营业部买入的股票受到更多关注,相应的市场反应也更加显著。进一步的研究表明监管性信息披露引发的投资者关注通过降低市场信息不对称抑制了股价反转。     

Informed Trading in Stock and Option Markets

We investigate the contribution of option markets to price discovery, using a modification of Hasbrouck's (1995) "information share" approach. Based on five years of stock and options data for 60 firms, we estimate the option market's contribution to price discovery to be about 17% on average. Option market price discovery is related to trading volume and spreads in both markets, and stock volatility. Price discovery across option strike prices is related to leverage, trading volume, and spreads. Our results are consistent with theoretical arguments that informed investors trade in both stock and option markets, suggesting an important informational role for options.     

On the Stability of the Cross‐Section of Expected Stock Returns in the Cross‐Section: Understanding the Curious Role of Share Turnover

In this paper, we shed further light on cross‐sectional predictors of stock return performance. Specifically, we explore whether the cross‐section of expected stock returns is robust within stock groups sorted by past monthly return. We find that the book/market and momentum effects are remarkably robust to sorting on past returns. However, share turnover is negatively related to future returns for stocks with abnormally low stock price performance in the recent past, but postively related to returns for well‐performing stocks. This casts doubt on the use of turnover as a liquidity proxy, but is consistent with turnover being a proxy for momentum trading which pushes prices in the direction of past price movements. Our results are robust to both NYSE/AMEX and Nasdaq stocks, and also robust to stratifying the sample by time period.     

Volume,volatility and information linkages in the stock and option markets

This paper examines the relationship between option trading activity and stock market volatility. Although the option market is uniquely suited for trading on volatility information, there is little analysis on how trading activity in this market is linked to stock price volatility. The bulk of the discussion tends to focus on whether trading activity in the stock market is informative about stock volatility. To analyze the information in option trading activity for stock market volatility, a sample of 15 stocks with the highest option trading volume is selected. For each stock, it is noted that the trading activities in the put and call option markets have significant explanatory power for stock market volatility. In addition, the results indicate that the call option trading activity has a stronger impact on stock volatility compared with that of the put options. Our results demonstrate that information and sentiment in the option market is useful for the estimation of stock market volatility. Also, the significance of the effects of option trading activity on stock price volatility is observed to be comparable to that of stock market trading activity. Furthermore, the persistence and asymmetric effects in the volatility of some stocks tend to disappear once option trading activity is taken into account.     

Internet search intensity,liquidity and returns in emerging markets

Using a sample of listed companies in the Vietnam stock market from 2013 to 2018, this paper investigates the linkage between Internet search intenseness and stock returns and trading volume. The empirical results confirm the “price pressure hypothesis” that search intensity is positively associated with subsequent stock returns and trading volume. It also finds that the positive effects on stock returns are not temporary but remain for the long term although some reversals occur. The results show that the effects of search intensity on stock returns are higher for large stocks than for small stocks. The findings also reveal that stocks that attract more attention from the public are exposed to higher market risk. These findings have not been documented in the literature so they enrich the information on the relationship between Internet search intenseness and stock market returns, especially for emerging markets where Internet user numbers are sharply increasing.     

Transmission of shocks from cross-listed markets to the return and volatility of domestic stocks

This paper examines the transmission of information from German and the U.S. markets to domestic markets using daily price and volume data of 264 stocks from 26 countries that are traded in their home country and cross-listed outside their home market as depository receipts (DRs); in the German market as Global Depository Receipts (GDRs) and in the U.S. as American Depository Receipts (ADRs). We identify days with significant news arrivals in a market through minimum thresholds for both significant absolute price change and trading volume. DR returns and volatilities are affected by the shocks in the markets where they are cross-listed controlling for domestic shocks. Contemporaneous and/or lagged shocks to the cross-listed markets are transmitted to domestic stock returns and volatilities. South American DRs are affected mostly by U.S. shocks, while Eastern European DRs show greater reaction to the German shocks.