Opportunism,overconfidence and irrationality: A puzzling triad

We empirically investigate managerial decision-making in a corporate context with combinations of rational/irrational managers and investors. There are noticeable differences in insider trading among these groups, particularly when exposed to market-wide and firm-level sentiment. We find that investor sentiment in the presence of managerial overconfidence has a significant impact on insider trading. We also show that managers behave opportunistically when timing stock splits and undertaking insider trading. Our findings linking splits to insider trading is robust under various specifications. In cases where irrational managers coexist with irrational investors, our study demonstrates important implications for the firms involved.     

Sentiment stocks

To study how investor sentiment at the firm level affects stock returns, we match more than 58 million social media messages in China with listed firms and construct a measure of individual stock sentiment based on the tone of those messages. We document that positive investor sentiment predicts higher stock risk-adjusted returns in the very short term followed by price reversals. This association between stock sentiment and stock returns is not explained by observable stock characteristics, unobservable time-invariant characteristics, market-wide sentiment, overreaction to news, or changing investor attention. Consistent with theories of investor sentiment, we find that the link between sentiment and stock returns is mainly driven by positive sentiment and non-professional investors. Finally, exploiting a unique feature of the Chinese stock market, we are able to isolate the causal effect of sentiment on stock returns from confounding factors.     

An Empirical Investigation of Herding Behavior in the U.S. REIT Market

Our study investigates the market-wide herding behavior in the U.S. equity REIT market. Utilizing the quantile regression method, we find that herding is more likely to be present in the high quantiles of the REIT return dispersion. This implies that REIT investors tend to herd under turbulent market conditions. Our results also support the asymmetry of herding behaviors, that is, herding is more likely to occur and becomes stronger in declining markets than in rising markets. In addition, our findings show that the current financial crisis has caused a change in the circumstances under which herding can occur, as we find that during the current crisis REIT investors may not start to herd until the market becomes extremely turbulent whereas during the relatively normal period before the crisis, investors tend to herd when the market is moderately turbulent. Finally, we find that compared with the case of the ‘pre-modern’ era, REIT investors are more likely to herd in the ‘modern’ era, during which herding usually occurs when the market becomes tumultuous. This implies that the switch of REITs from passive externally managed entities into active self-managed ones has made the investors more responsive to market sentiment.     

US and Domestic Market Gains and Asian Investors’ Overconfident Trading Behavior

We find that subsequent to both US and domestic market gains, both Asian individual and institutional investors increase their trading and that this effect is more pronounced in bull markets, in periods of relatively favorable investor sentiment, in periods of extremely high market returns, and in markets with short‐sale constraints. We also find that individual investors trade more in response to market gains than institutional investors. Moreover, we find that further integration of Asian stock markets with US stock markets after the Asian financial crisis in 1998 is an important reason for Asian investors’ response to US market gains.     

What drove the mid-2000s explosiveness in alternative energy stock prices? Evidence from U.S., European and global indices

Soaring prices in European alternative energy stocks and their subsequent tumble have attracted attention both from investors and academics. We extend recent research to an international setting and analyze whether the explosive price behavior of the mid-2000s was driven by rising crude oil prices and overall bullish market sentiment. Inflation-adjusted U.S. alternative energy stock prices do not exhibit signs of explosiveness. By contrast, we find strong evidence of explosive price behavior for European and global sector indices, even after controlling for a set of explanatory variables. Interestingly, while the sector indices plunged with the outbreak of the global financial crisis, idiosyncratic components continued to rise and did not start to decline until after world equity markets had already begun to recover in 2009. This finding suggests a substantial revaluation of alternative energy stock prices in light of intensifying sector competition and shrinking sales margins and casts some doubts on the existence of a speculative bubble. Nevertheless, we observe temporary episodes of explosiveness between 2005 and 2007 followed by rapid collapses, indicating the presence of some irrational exuberance among investors.     

透视中国上市公司的“迎合投资”行为

采用2003～2008年中国沪深股票市场的A股上市公司作为研究样本,在市场非理性背景下研究投资者情绪对上市公司投资行为的影响。区分市场情绪低落和高涨时期,发现只有在市场情绪高涨时期公司投资才对投资者情绪敏感;而在市场情绪低落时期,上市公司通过盈余管理导致错误定价配合公司投资决策。作为投资者短视代表的换手率对上市公司迎合投资行为的影响呈倒U型,说明并不是换手率越高,公司投资对投资者情绪的迎合越明显。     

中国个人投资者处置效应研究——一个非理性信念的视角

处置效应是指投资者过早卖出盈利股票而长期持有亏损股票的现象。大量文献表明金融市场投资者存在显著的处置效应,但其产生的原因和机理存在争议。本文在前景理论框架下,构建了包含投资者非理性预期的离散时间投资组合决策模型,发现处置效应随投资者情绪升高而减弱。本文使用我国某券商2007—2009年近177万个人投资者股票账户的交易数据进行了实证分析,得到与理论模型预测的一致结果,即投资者情绪与投资者处置效应之间呈现显著的负相关关系。而且,受情绪影响,投资者处置效应在估值难度较大的股票中更弱。本文结论对理解投资者处置效应、优化投资者卖出决策和加强资本市场基础制度建设具有一定理论和实践意义。     

Does investor sentiment really matter?

We examine the role sentiment plays and its manifestation in the trading behavior of investors in the U.S. stock market. Our findings support the notion that sentiment-induced buying and selling is an important determinant of stock price variation. While ‘classical’ asset pricing categorizes investors who trade in ways not consistent with mean-variance optimization as ‘irrational,’ we show that this traditional view should not hastily be evoked to characterize sentiment-driven investing. We instead show that sentiment-driven investors can trade against the herd and sell when prices are overinflated as a result of over-bullishness and vice versa. The asset pricing implications of this paper are that sentiment is linked to shifts in risk tolerance and this triggers contrarian-type behavior. In sum, we uncover the following regarding the behavior of sentiment-driven investors; firstly, they are more apt to trade on survey-based indicators rather than market-based indicators. Secondly, they trade on the basis of information extracted from individual, rather than institutional, investor surveys. Thirdly, they respond asymmetrically to shifts in sentiment and trade more aggressively during periods of declining sentiment. Finally, there is asymmetry in the role of sentiment with respect to business conditions whereby such buying and selling is more pronounced during bear markets.     

Investor sentiment and return predictability of disagreement

This study examines the influence of investor sentiment on the relationship between disagreement among investors and future stock market returns. We find that the relationship between disagreement and future stock market returns time-varies with the degree of investor sentiment. Higher disagreement among investors’ opinions predicts significantly lower future stock market returns during high-sentiment periods, but it has no significant effect on future stock market returns during low-sentiment periods. Our findings imply that investor sentiment is related to several causes of short-sale impediments suggested in the previous literature on investor sentiment, and that the stock return predictability of disagreement is driven by investor sentiment. We demonstrate that investor sentiment has a significant impact on the stock market return predictability of disagreement through in-sample and out-of-sample analyses. In addition, the profitability of our suggested trading strategy exploiting disagreement and investor sentiment level confirms the economic significance of incorporating investor sentiment into the relationship between disagreement among investors and future stock market returns.     

Do sentiment trades explain investor overconfidence around analyst recommendation revisions?

This study examines irrational stock market reactions to analyst recommendation revisions depending on investor sentiment levels prior to analyst report announcements. We construct a firm-specific sentiment indicator by extending Huang et al. (2015, Review of Financial Studies, 28, pp.791–837). Analyst recommendation revisions have more pronounced effects for downgrades, which is attributable to sentiment effects. Domestic investors tend to react less to upgrades (downgrades) news when their prior beliefs are pessimistic (optimistic), implying that they are overconfident. The domestic investors drive sentiment trades, whereas foreign investors are not biased.     

Understanding Investor Sentiment: The Case of Soccer

We examine the extent to which the stock market's inefficient responses to resolutions of uncertainty depend on investors’ biased ex ante beliefs regarding the probability distribution of future event outcomes or their ex post irrational reactions to these outcomes. We use a sample of publicly traded European soccer clubs and analyze their returns around important matches. Using a novel proxy for investors’ expectations based on contracts traded on betting exchanges (prediction markets), we find that within our sample, investor sentiment is attributable, in part, to a systematic bias in investors’ ex ante expectations. Investors are overly optimistic about their teams’ prospects ex ante and, on average, end up disappointed ex post, leading to negative postgame abnormal returns. Our evidence may have important implications for firms’ investment decisions and corporate control transactions.     

Stock market short-termism—an international perspective

This study uses a VAR approach with a time-varying risk premium to see if stock market investors are short-term oriented, placing too much weight on current and near cash flows. Using aggregate stock market data for Australia, Germany, Japan, USA and UK markets (1977–1999), we find the degree of persistent under-valuation of future cash flows is far higher in the UK relative to the other countries in our sample, and is market-wide. Also, over the period, US investors appear to have consistently underestimated long horizon cash flows in current stock market valuations relative to a rational valuation model.     

Noise trading and stock market volatility

We investigate the relative effects of fundamental and noise trading on the formation of conditional volatility. We find significant positive (negative) effects of investor sentiments on stock returns (volatilities) for both individual and institutional investors. There are greater positive effects of rational sentiments on stock returns than irrational sentiments. Conversely, there are significant (insignificant) negative effects of irrational (rational) sentiments on volatility. Also, we find asymmetric (symmetric) spillover effects of irrational (rational) bullish and bearish sentiments on the stock market. Evidence in favor of irrational sentiments is consistent with the view that investor error is a significant determinant of stock volatilities.     

Price leadership and asynchronous movements of multi-market listed stocks

We examine the asynchronous price movements of the same assets traded on multiple markets, each of which has its unique characteristics. Differently from the existing literature, we use a dynamic structural Vector Autoregressive (VAR) setting to explore the effects of market-wide and idiosyncratic shocks on both home and host listings. We find strong evidence that foreign prices lead home prices, but not the reverse effect. Contrary to theory predictions, investors in the firms’ home market respond to idiosyncratic fluctuations in the stock returns in the host markets. Our results suggest that investors pay attention to fluctuations in the stocks listed on the more institutionally developed markets.     

Investor sentiment and economic forces

Economic theory suggests that pervasive factors should be priced in the cross-section of stock returns. However, our evidence shows that portfolios with higher risk exposure do not earn higher returns. More importantly, our evidence shows a striking two-regime pattern for all 10 macro-related factors: high-risk portfolios earn significantly higher returns than low-risk portfolios following low-sentiment periods, whereas the exact opposite occurs following high-sentiment periods. These findings are consistent with a setting in which market-wide sentiment is combined with short-sale impediments and sentiment-driven investors undermine the traditional risk-return tradeoff, especially during high-sentiment periods.     

Intraday online investor sentiment and return patterns in the U.S. stock market

We implement a novel approach to derive investor sentiment from messages posted on social media before we explore the relation between online investor sentiment and intraday stock returns. Using an extensive dataset of messages posted on the microblogging platform StockTwits, we construct a lexicon of words used by online investors when they share opinions and ideas about the bullishness or the bearishness of the stock market. We demonstrate that a transparent and replicable approach significantly outperforms standard dictionary-based methods used in the literature while remaining competitive with more complex machine learning algorithms. Aggregating individual message sentiment at half-hour intervals, we provide empirical evidence that online investor sentiment helps forecast intraday stock index returns. After controlling for past market returns, we find that the first half-hour change in investor sentiment predicts the last half-hour S&P 500 index ETF return. Examining users’ self-reported investment approach, holding period and experience level, we find that the intraday sentiment effect is driven by the shift in the sentiment of novice traders. Overall, our results provide direct empirical evidence of sentiment-driven noise trading at the intraday level.     

Crowd wisdom and internet searches: What happens when investors search for stocks?

Search engines and social media have become popular among investors as tools for finding and sharing information. The investor social media gathers a large amount of investor-generated content (IGC), which reflects the crowd wisdom of investors, while search engines help investors increase their chances of finding them. In this study, we integrate investor search behavior data from the Baidu Index and investor crowd wisdom data from Eastmoney Guba to assemble a unique data set at the daily level. We then describe and quantify crowd wisdom from investor-generated content (IGC) using three dimensions (IGC average sentiment, IGC sentiment volatility, and IGC increased volume) to investigate the impact of crowd wisdom in the relationship between investors' Internet searches and next-day stock returns. In our empirical analysis, we find that IGC average sentiment strengthens the relationship between investors' Internet searches and next-day stock returns, while IGC sentiment volatility and IGC increased volume have negative effects. These moderating effects are also moderated by institutional investor attention, search terminal preference, and content reading volume. These findings help to explain the value and impact of crowd wisdom when investors search for stock information through the Internet.     

Firm-specific information,analysts' superiority and investment value

Using a sample of Chinese security analysts’recommendations from 2005 to2010,we examine the source of analysts’superiority and the investment value of their recommendations.Using a calendar-time portfolio approach,we find that,on average,analysts’recommendations are valuable and that analysts are better at analyzing and transferring firm-specific information than market-wide or industry-level information.In addition,we show that the investment value of recommendations increases as firm-specific information becomes more important in stock pricing.Our empirical results are useful in guiding investors and helping brokerage houses to evaluate the output of research departments.     

The Effect of Investor Sentiment on Feedback Trading and Trading Frequency: Evidence from Taiwan Intraday Data

Abstract

Although extensive literature has suggested that investor sentiment may be one of the most important factors in explaining investor trading frequency and trading strategies, how individual investors are significantly influenced by sentiment remains underexplored. The feature of numerous individual investors in the Taiwan stock market provides an avenue to examine the relationship of investor sentiment to trading frequency and positive-feedback trading according to intraday data. Using a vector autoregression model to measure feedback trading in one-minute intervals, we find that trading frequency appears to increase in periods of rising market, suggesting that investor sentiment–driven trading increases market trading frequency without relying on past experiences to conduct trading behavior.     

Profitability of return and sentiment-based investment strategies in US futures markets

Our study adds to the literature by providing initial evidence on the interaction between short-horizon return predictability and investors’ sentiment by traders’ types on US commodity futures market. We find that the short-term contrarian profit is more associated with an increase rather than a decrease in hedgers’ sentiment. However, the interaction between lagged return and past change in speculators’ sentiment illustrates that the short-term contrarian profit is more associated with a decrease rather than an increase in sentiment. Based on behavioral finance theories, we conclude that hedgers behave like irrational traders while speculators behave like rational ones. Using Chou et al. (2007) decomposition, our results confirm the obtained relations between change in trader's sentiment and the overreaction. By expanding this decomposition, we find that the winners’ portfolio tends to more overreact with futures specific information. Also, the cross-autocorrelation between winners and losers and between losers and winners can represent another source of contrarian profits.