Abnormal Trading Research Articles

CEO-related announcements, trading activity, and calendar effects

ABSTRACT This study examines how abnormal trading volumes reflect new information, such as CEO-related announcements. Using hand-collected data on 1,236 CEO reappointments and turnovers from Polish firms listed on the Warsaw Stock Exchange, we show that investor reaction to CEO-related announcements is stronger in the winter-spring season than in the summer-fall season. However, in the summer-fall season, CEO reappointment triggers higher trading activity than CEO turnover announcements, while in the winter-spring season, the reaction is opposite. We also discover that abnormal trading volumes induced by CEO-related announcements are significantly lower at the beginning and end of the week than in the middle of the week. Furthermore, when it comes to day of the week anomalies, investors are much less interested in CEO reappointment than in turnover. The findings suggest that calendar effects influence investor reactions to CEO appointments, offering new insights into market anomalies and corporate governance mechanisms.

Nonfinancial 8-K disclosures and individual investors' trading during earnings announcement window

PurposeThis study investigates the influence of nonfinancial 8-K disclosures released during the earnings announcement window on the abnormal trading activities of individual investors.Design/methodology/approachWe employ regression analysis in this empirical study to examine the impact of nonfinancial 8-K filings on individual investors' abnormal trading activities.FindingsOur results reveal that individual investors exhibit higher levels of abnormal trading activities when firms release nonfinancial 8-Ks during the (0,1) window of earnings announcements. This effect is observed for both buyer-initiated and seller-initiated transactions and is particularly pronounced for firms reporting an operating loss. Negative sentiment in 8-Ks significantly intensifies such effect. Additionally, we find that buy-sell consensus increases significantly with concurrent nonfinancial 8-Ks. This suggests that 8-Ks may reduce information noise, leading individuals to trade with greater conviction.Originality/valueOur study examines the joint influence of nonfinancial 8-Ks and earnings announcements on individual investors' trading activities, thereby providing a novel perspective on the mechanisms through which 8-K filings affect individual investors' trading behaviors.

Exploring Anomaly Detection and Risk Assessment in Financial Markets Using Deep Neural Networks

In this paper, deep learning technology, along with a Gated Recurrent Unit (GRU) combined with an attention mechanism, is used to enhance the recognition ability and risk assessment accuracy of abnormal trading behavior in financial markets. The GRU effectively solves the problem of gradient vanishing in traditional recurrent neural networks through its unique gated structure, allowing the model to learn more stable and effective feature representations in long sequence data. On this basis, the contextual attention (CA) module in the attention mechanism is introduced, enabling the model to automatically learn and assign different weights to various parts of the input sequence. Combined with bidirectional GRU and the attention mechanism, the model can not only capture temporal dependencies in the sequence, but also highlight the key features that affect market anomalies, thus improving the model's ability to understand complex market dynamics.

The impact of social distancing on trading activity during the COVID‐19 pandemic

AbstractI explore the impact of social distancing on trading activity during the COVID‐19 pandemic using real‐time location tracking data from Facebook users. I find that stocks categorized as “harder‐to‐value,” which are typically smaller, less transparent, less visible, and less profitable, experience decreased abnormal trading with more social distancing in their headquarters counties. In contrast, “easier‐to‐value” stocks show an increase in abnormal trading due to high social distancing in their headquarters counties. These findings indicate that greater firm‐specific information asymmetry arises from increased social distancing within the firm headquarters counties. Although “easier‐to‐value” stocks can use alternative information sources to mitigate the information asymmetry, “harder‐to‐value” stocks fail to do so and face negative impact on trading. Additional analyses using alternative information channels, market sidedness, and liquidity confirm this hypothesis.

How do abnormal trading behaviors diffuse in electronic markets?

How do abnormal trading behaviors diffuse in electronic markets?

Institutional/retail investor active attention and behavior: Firm coverage on Mad Money

We find that firm coverage on the popular Mad Money Show is significantly associated with institutional and retail investor active attention, proxied by SEC EDGAR queries and posts on StockTwits. The association strengths differ by recommendation directions (buy or sell) and a firm’s exposure on the Show. The associations remain after controlling for selection bias, other firm-specific news, and moderating events (e.g., Superbowl and Olympics). The increased investor active attention is associated subsequently with abnormal trading volumes and short-sales activities of institutional/retail investors, and retail investor portfolios. While the opening price captures most of the significant association between Show coverage and next day’s returns, the extent of subsequent reversals varies by Show segment, recommendation direction and moderators (e.g., firm-coverage frequency on the same Show). No abnormal returns are associated with any pre-Show publicity about upcoming guest interviews. Our findings are consistent with the association of the media and its potential influencers with the limited active attention budgets of investors, different behaviors of retail and institutional investors, and the shorting of contrarian investors.

Forecasting carbon prices under diversified attention: A dynamic model averaging approach with common factors

To improve the predictability of carbon prices under diversified attention, this paper develops a dynamic model averaging approach with common factors (DMA-CF) which uses dimension-reduction techniques to extract factors from all models including the subsets of attention predictors and allows time-varying coefficients and model switching. The in-sample results using univariate models reveal the strong predictive power of the attention measured by the Google search volume index (AGSVI). The out-of-sample results confirm it as the strongest attention predictor, and show the superior performance of DMA-CFs relative to the original DMA and the benchmark. We further investigate how common factors improve the forecasting performance of DMA. The empirical evidence indicates that common factors efficiently aggregate the information and reduce the estimation errors in complicated models which are assigned with higher probability in DMA-CFs than in DMA, thereby digging out more predictive information for forecasting carbon prices. Moreover, DMA primarily depends on AGSVI, with the highest weights, while DMA-CFs slightly downweight the AGSVI and allocate more weight to the attention proxy of abnormal trading volume (AAVol) which provides complementary information. Finally, our DMA-CF methods can improve the economic gains in the portfolio exercise with carbon futures.

Investing while lending: Do index funds improve managerial information disclosure?

Securities lending activities have become pervasive among index funds in recent decades, yet its impact on information disclosure remains unclear. In this paper, we jointly investigate the information disclosure impact of both investing and lending activities of index funds, using a sample of the U.S. firms for 2002–2017. On the one hand, we document that securities lending deteriorates the information environment of public firms. On the other, index fund holdings are associated with greater information transparency and less bad news hoarding by firm managers, after controlling for the opposing effects from securities lending. This finding survives a battery of robustness tests and is more pronounced in a small sample using the Russell 1000/2000 index reconstitution as a source of plausibly exogenous variation in index fund holdings. We also document a negative association between index ownership and abnormal trading activities around stock price crash weeks. Our findings support the view that regardless of their pervasive securities lending engagement and passive investing strategies, index funds impose an overall favourable impact on information environment of public firms.

Political polarization in financial news

Comparing coverage of the same corporate financial news by the conservative Wall Street Journal and the liberal New York Times, we find strong evidence of political polarization in their reporting on both the intensive and extensive margins of coverage. We show that this politics-induced disagreement in corporate financial news leads to an increase in abnormal trading volume for the most politically extreme firms. Our results highlight a new source of investor disagreement, arising out of polarized reporting of corporate financial news, that generates trade among investors.

Persistence or reversal? The effects of abnormal trading volume on stock returns

Having established that portfolios derived from the extreme deciles of Abnormal Trading Volume (ATV) generate positive (negative) returns in the short (long) run, we devise a measure of Persistence in ATV (PATV) and provide an investor sentiment-based explanation for this return predictability. PATV leads to portfolio returns continuing to drift in the short run. However, the trading volumes of individual stocks in the portfolios gradually revert to their long-run means, accompanied by portfolio returns falling and turning negative as mispricing is corrected. We dismiss liquidity shocks, continuing overreaction, and investor disagreement and attention as explanations for the observed return predictability.

Abnormal Trading Visualized Detection on Bitcoin Transaction Based on Semi-Supervised Machine Learning and Graph Database

Abnormal Trading Visualized Detection on Bitcoin Transaction Based on Semi-Supervised Machine Learning and Graph Database

Market Timing and Asymmetric Information: How do Rights Issues and Private Placements Attract Investors to Overvalued Stocks?

Manuscript type: Research paper Research aims: This study examines the background of selecting the equity offering mechanism between rights issues and private placements when facing asymmetric information and overvalued prices. Design/Methodology/Approach: This research employs the concept of information asymmetry and focuses on analysing market timing data about stock offering transactions in Indonesia from 2000 to 2020. This study uses regression analysis to examine the correlation between information asymmetry and trade volume. Abnormal trade volume before various offerings is subjected to regression analysis using generally used proxies for information asymmetry. Research findings: The conclusions of our research indicate that companies that issue more shares than the overpriced stock tend to exhibit a more excellent abnormal return value in the context of rights issues. The sales volume indicates the company’s prospects derived from private information obtained during the offering Theoretical contribution/Originality: There is a shortage of existing literature about research that specifically investigates the identification of SEO techniques that elicit negative market responses. Consequently, this study explores the connection between the underlying motivations driving the selection of stock offering mechanisms. Practitioner/Policy implication: The distribution of profits in the transaction indicates the company’s future policies. Before investing, investors can acquire pertinent information on the company’s current state, strategic goals, and prospects. Research limitation: The present analysis has not considered the factors of internal ownership or insider trading. These factors might serve as a foundation for investigating the underlying incentives for issuing shares with more precise market timing considerations.

Corporate bond price reversals

I demonstrate empirically that corporate bond dealers mitigate adverse selection risk by passing potentially informed transactions to institutional investors. I contrast price reversals following days with abnormal trading volume across bonds with different information asymmetry. In informed trading, the part of reversal specific to high-volume days should increase with information asymmetry. In uninformed trading, there is no such effect. Following high-volume days when investors provide liquidity, the reversals are consistent with the former case. When dealers provide liquidity, I observe the latter. The results suggest that the informational content of bond prices is higher when dealers do not take inventory.

Disagreement about public information quality and informational price efficiency

Investors often hold differing opinions on public information quality. This paper shows that such investor disagreement provides a novel explanation for financial market dynamics around earnings announcements. We propose a rational expectations equilibrium model where investors disagree about the precision of a public signal, which separates a pre-news trading period from a post-news trading period. In equilibrium, investor disagreement about public signal precision diminishes informational price efficiency before the news, but enhances it afterward. Consequently, investor disagreement leads to a notable jump in informed trading around the news, a decline in abnormal trading volume before the news and a surge immediately after the news, and underreaction of stock price to announced earnings.

Investors' opinion disagreement and abnormal trading around pre-earnings announcements

We use textual analysis techniques to construct a direct measure of investor disagreement to explain the abnormal stock volume and return around earnings expectation announcement in China. We crawl scrape the most a popular Chinese stock forum for individuals' posts about their opinion on a stocks, and classify the posts with machine learning methods. We find that our measure is most correlated with return volatility and historical turnover. We then conduct an event study for abnormal stock volume around pre-earnings announcements, examining the cumulative abnormal turnover for sample groups with prior agreement or disagreement, and with a convergence or divergence of opinion. We find that given prior disagreement of opinion, both convergence and divergence of opinion causing more trading volume in the Chinese market. We also observe the sample group with a divergence of opinion has more cumulative abnormal return than the convergence group. However, this effect is found to be more profound in stocks with higher institutional ownership, which is believed to be correlated with a low short-sale constraint.

Informativeness of Key Audit Matters: Evidence from China

SUMMARY This study examines whether the key audit matters (KAMs) disclosed in expanded audit reports as a part of recent regulatory reforms are informative for investors in an emerging economy setting. Using the recent adoption of expanded audit reports for firms listed exclusively in Mainland China, we find robust evidence that the abnormal trading volume and earnings response coefficients are higher and that stock price synchronicity is lower during the postadoption than preadoption period. In additional tests, we find evidence that KAMs are more informative for non-state-owned enterprises, smaller firms, and firms with a smaller analyst following. Finally, we find that investors respond to the characteristics of KAM disclosures, providing corroborative evidence of the informativeness of these disclosures. Overall, our study provides systematic evidence that KAMs are incrementally informative for investors in an emerging economy. Data Availability: The data are available from the public sources cited in the text. JEL Classifications: M41; M42; M48.

Impact of Increased Uncertainty due to COVID-19 on Analyst Research Reports

This study investigated the implications of Covid-19 induced non-face-to-face remote work environment on analysts’ reports. Employing an empirical analysis of the Korean market from 2016 to 2021, we reveal that research reports during the Covid-19 period exhibit larger prediction errors compared to the pre-Covid era. Despite the reduced accuracy, abnormal trading volumes were observed on the publication dates of reports during this period. Furthermore, these effects are particularly pronounced in reports issued by large brokerage firms with “Buy” recommendations and among foreign investors. Our findings highlight that the pandemic’s non-face-to-face environment has heightened uncertainty in research analysts’ predictions, leading to a decline in reporting accuracy. However, despite these challenges, there is an increase in demand for information from investors, and the impact of the analyst report on the financial market may be greater due to the higher demand for information from investors.

Investor attention during soccer World Cups

PurposeThis study aims to examine investor attention by exploring the trading behavior of investors in US-based exchange traded funds (ETFs) of countries active in the Federation Internationale de Football Association (FIFA) World Cups.Design/methodology/approachThe present study employs event study methodology to measure abnormal returns and excess trading volume of country-specific ETFs during six FIFA World Cups. The sample of ETFs includes 19 participating countries.FindingsConsistent with investor behavior that might be explained by attention effect, the study finds that country-specific ETFs from participating countries do indeed behave differently during FIFA World Cups events. The authors find significant evidence of abnormal trading volume and, albeit weaker, abnormal returns during cups.Originality/valueThis study contributes to the literature on investor behavior, linking investor attention with salient sports events.

Do rights matter? An intraday analysis of rights issues in Australia

AbstractWe examine intraday abnormal returns associated with rights issue announcements in the Australian equity market over the period January 2000 to December 2022. Consistent with prior studies, we find significant abnormal returns ranging from −2.9% to −2.7% on the event day. We provide the first evidence on intraday price reactions pertaining to rights issues in Australia. Within 15 min of an announcement, we find significant abnormal trade returns of −1.2%. However, market participants are unable to profit by trading on these announcements due to transaction costs. Our results imply that the information content is fully impounded within 90 min.

The Booms and Busts of Beta Arbitrage

Low-beta stocks deliver high average returns and low risk relative to high-beta stocks, an opportunity for professional investors to “arbitrage” away. We argue that beta-arbitrage activity generates booms and busts in the strategy’s abnormal trading profits. In times of low arbitrage activity, the beta-arbitrage strategy exhibits delayed correction, taking up to three years for abnormal returns to be realized. In contrast, when arbitrage activity is high, prices overshoot and then revert in the long run. We document a novel positive-feedback channel operating through firm leverage that facilitates these boom-and-bust cycles. This paper was accepted by Lukas Schmid, finance. Funding: This work is financially supported by National Natural Science Foundation of China [NSFC Grant Number 72303226] and the Key Program of National Natural Science Foundation of China [NSFC Grant Number 72233003]. Supplemental Material: The internet appendix and data are available at https://doi.org/10.1287/mnsc.2023.4929 .