Overconfident individual day traders: Evidence from the Taiwan futures market

A specific day-trading policy in Taiwan futures market allows an investigation of the performance of day traders. Since October 2007, investors who characterize themselves as “day traders” by closing their day-trade positions on the same day enjoy a 50% reduction in the initial margin. Because we can identify day traders ex ante, we have a laboratory to explore trading behavior without the contamination of potential behavioral biases. Our results show that the 3470 individual day traders in the sample incur on average a significant loss of 61,500 (26,700) New Taiwan dollars after (before) transaction costs over October 2007–September 2008. This implies that day traders are not only overconfident about the accuracy of their information but also biased in their interpretations of information. We also find that excessive trading is hazardous only to the overconfident losers, but not to the winners. Last, we provide evidence that more experienced individual investors exhibit more aggressive day trading behavior, although they do not learn their types or gain superior trading skills that could mitigate their losses.     

Who is the more overconfident trader? Individual vs. institutional investors

Guided by the Gervais and Odean (2001) overconfident trading hypothesis, we comprehensively investigate the trading behavior of individual vs. institutional investors in Taiwan in an attempt to identify who is the more overconfident trader. Conditional on the various states of the market, on market volatility, and on the risk level of the securities they trade, we find that both individual and institutional investors trade more aggressively following market gains in bull markets, in up-market states, in up-momentum market states, and in low-volatility market states and that only individual investors trade more in riskier securities following market gains. More importantly, we find that individual investors trade more aggressively following market gains in the three conditional states of the market and in high-volatility market states than institutional investors. Also, individual investors trade more in relatively riskier securities following gains than institutional investors. These findings provide evidence that individual investors are more overconfident traders than institutional investors.     

WHAT DRIVES INVESTMENT FLOWS INTO SOCIAL TRADING PORTFOLIOS?

We investigate investment flows into more than 5,300 social trading portfolios that are issued as structured products and are tradable at a regular exchange. We find that investment flows chase past performance. However, in contrast to mutual fund flows, the flow–performance relation exists nearly exclusively for the best performing social trading portfolios. Flows follow raw returns rather than factor model alphas. Additionally, flows are highly persistent. Finally, social trading portfolios with higher visibility on the web page of the social trading platform as well as traders communicating actively to investors via public comments attract higher inflows.     

Individual home bias,portfolio churning and performance

This study investigates economic consequences of individual investors’ home bias and portfolio churning in their personal pension accounts. The empirical analysis is carried out within a Heckman style two-stage framework to account for selection bias with respect to individuals’ investment activity, and to allow for an endogenously determined home bias, portfolio churning and performance. Results indicate that home bias induces a worse risk-adjusted performance. Home-biased individuals’ relatively bad performance originates in insufficient risk-reduction, due to a lack of international diversification. A higher degree of portfolio churning also deteriorates performance, despite the fact that churning is not associated with any direct transaction costs. However, home-biased individuals do not churn portfolios as often as individuals with a larger share of international asset holdings, which diminishes the negative effects of home bias on performance. Overconfidence is driven by a return-chasing behavior, where overconfident individuals favor international assets with high historical returns. Individuals with actual skill are more often men than women, are not tempted by high historical returns, and use international assets for the right reason – diversification.     

Investor Overconfidence and Trading Volume

The proposition that investors are overconfident about theirvaluation and trading skills can explain high observed tradingvolume. With biased self-attribution, the level of investoroverconfidence and thus trading volume varies with past returns.We test the trading volume predictions of formal overconfidencemodels and find that share turnover is positively related tolagged returns for many months. The relationship holds for bothmarket-wide and individual security turnover, which we interpretas evidence of investor overconfidence and the disposition effect,respectively. Security volume is more responsive to market returnshocks than to security return shocks, and both relationshipsare more pronounced in small-cap stocks and in earlier periodswhere individual investors hold a greater proportion of shares.(JEL G11, G12)     

Acquisitions,Overconfident Managers and Self‐attribution Bias

We examine whether acquisitions by overconfident managers generate superior abnormal returns and whether managerial overconfidence stems from self‐attribution. Self‐attribution bias suggests that overconfidence plays a greater role in higher order acquisition deals predicting lower wealth effects for higher order acquisition deals. Using two alternative measures of overconfidence (1) high order acquisition deals and (2) insider dealings we find evidence supporting the view that average stock returns are related to managerial overconfidence. Overconfident bidders realise lower announcement returns than rational bidders and exhibit poor long‐term performance. Second, we find that managerial overconfidence stems from self‐attribution bias. Specifically, we find that high‐order acquisitions (five or more deals within a three‐year period) are associated with lower wealth effects than low‐order acquisitions (first deals). That is, managers tend to credit the initial success to their own ability and therefore become overconfident and engage in more deals. In our analysis we control for endogeneity of the decision to engage in high‐order acquisitions and find evidence that does not support the self‐selection of excessive acquisitive firms. Our analysis is robust to the influence of merger waves, industry shocks, and macroeconomic conditions.     

Option trading and individual investor performance

This paper examines the impact of option trading on individual investor performance. The results show that most investors incur substantial losses on their option investments, which are much larger than the losses from equity trading. We attribute the detrimental impact of option trading on investor performance to poor market timing that results from overreaction to past stock market returns. High trading costs further contribute to the poor returns on option investments. Gambling and entertainment appear to be the most important motivations for trading options while hedging motives only play a minor role. We also provide strong evidence of performance persistence among option traders.     

Performance Manipulation and Fund Flow: Evidence from China

In this paper, we assess the relation between fund flow and fund returns in China's open-ended fund industry. Analyzing quarterly data from the period January 2005-December 2012, we construct a simultaneous equation model that captures the endogeneity of current and past returns and flows and find that contemporaneous returns have a key role in determining fund flows. We then estimate the fund performance "manipulation degree" to further investigate the performance manipulation effect on fund flows. We find that manipulated funds can attract an additional flow of money and that, notably, individual rather than institutional investors are more likely to be deceived by manipulative behavior.     

An empirical evaluation of the overconfidence hypothesis

Recently, several behavioral finance models based on the overconfidence hypothesis have been proposed to explain anomalous findings, including a short-term continuation (momentum) and a long-term reversal in stock returns. We characterize the overconfidence hypothesis by the following four testable implications: First, if investors are overconfident, they overreact to private information and underreact to public information. Second, market gains make overconfident investors trade more aggressively in subsequent periods. Third, excessive trading of overconfident investors in securities markets contributes to the observed excessive volatility. Fourth, overconfident investors underestimate risk and trade more in riskier securities. To document the presence of overconfidence in financial markets, we empirically evaluate these four hypotheses using aggregate data. Overall, we find empirical evidence in support of the four hypotheses.     

September 11 and Stock Return Expectations of Individual Investors

This study uses data that offers the unique opportunity to analyze how an unprecedented crisis such as the September 11 tragedy influences expected returns and volatility forecasts of individual investors. Via e-mail, we asked a randomly selected group of individual investors with accounts at a German online broker to answer an internet questionnaire at the beginning of August 2001. A second e-mail to the investors who had not yet answered, scheduled five weeks later, was postponed due to the terror attacks until September 20, which was exactly the day with the lowest share prices in Germany in the year 2001. Based on the answers to questions concerning stock market predictions, we find that return forecasts of the investors in our sample are significantly higher after September 11, suggesting a belief in mean reversion. Our results show that investors interpret the large drop in share prices during the ten day period after September 11 mainly as temporary rather than permanent. After the terror attacks, volatility forecasts are higher than before September 11. In two out of four cases, historical volatilities are overestimated. Therefore, investors are not generally overconfident in the way that they underestimate the variance of stock returns. Differences of opinion with regard to return forecasts are lower after the terror attacks whereas differences of opinion concerning volatility forecasts are mainly unaffected.We would like to thank William Goetzmann (the editor), Alexander Klos, Markus Nöth, Jens Reynders, Zacharias Sautner, an anonymous referee, several faculty members of the Fuqua School of Business, and seminar participants at the University of Mannheim for valuable comments and insights. Parts of this paper were written while Markus Glaser was visiting the Fuqua School of Business, Duke University, North Carolina, USA, whose support is gratefully acknowledged. Financial Support from the Deutsche Forschungsgemeinschaft (DFG) is also gratefully acknowledged.