Hosted by

Dr Shu Zhang Gillmore Centre Research Fellow

Speaker

Professor Lin Peng is the Krell Chair Professor in Finance at Zicklin School of Business, Baruch College, the City University of New York

The Power of Social Networks in Capital Markets: Insights from Large-Scale Data Analysis

As Aristotle famously noted, ''Humans are, by nature, social animals.'' Social networks' impacts on capital markets are likely to be even more important today because large-scale online social networks allow for easy communication among individuals that transcends the frictions associated with factors such as geographic distances.

On the one hand, social networks facilitate the flow of ideas and transmit valuable information. On the other hand, they can also spread rumours, amplify biases, influence individual beliefs, and trigger disagreements. These networks can thus exert substantial influence on investor and firm decisions in financial markets.

In this seminar, Prof Peng will present the latest research that uses large-scale, representative, real-world social network data to examine the effects of social networks on news diffusion, belief formation, trading, liquidity, and valuations of stocks.

 

Dr Shu Zhang Blog: The Influence of Social Networks on Financial Markets and Investor Behaviour

Introduction:

The impact of social networks on financial markets has become increasingly significant as investing is, at its core, a social activity. As online social networks transmit information to a broader audience at virtually zero marginal cost, they have the potential to shape economic and political outcomes. This report delves into the role of social networks in disseminating earnings news and the subsequent stock market reactions, revealing both the benefits and unintended consequences for investors.

The Role of Social Networks in Financial Markets:

Traditional finance models often ignore the social network dimension, assuming individuals form beliefs and make decisions in a social vacuum. However, social learning can positively impact investor decisions by disseminating valuable information, improving decision-making, and increasing market efficiency. Conversely, social networks can propagate incorrect beliefs, naive trading strategies, information cascades, and biases through social network transmission. The role of social networks in finance is context-specific and warrants further research.

Utilizing Social Media Data for Research:

To understand the impact of social networks on financial markets, researchers have used Facebook data as a proxy for the social network of investors in the US. Facebook is the largest social media platform with a representative user base, is convenient and publicly available, and allows for comparison and compatibility with existing literature. Social ties influence various economic outcomes, such as asset allocation choices, dissemination of innovation, and financial decision-making processes.

Impact on Market Reactions to Earnings News:

This paper on news diffusion in social networks and stock market reactions focuses on disseminating earnings news and the post-earnings announcement drift anomaly. The study shows significant price reactions, volatility, and volume responses for earnings announced by firms in high centrality locations, with weaker price drift and faster volatility decline in the post-announcement window. The results reveal that social networks, as measured by centrality, play a significant role in facilitating information dissemination and improving price efficiency in response to earnings news.

Investor Behaviour and Trading Activities:

Using stock tweets messages and household trading data, researchers analyse the role of social networks in information dissemination, investor attention, and the influence of social ties on trading activities and outcomes. Stronger social ties lead to faster price adjustments, more efficient price discovery, increased trading volume, and more persistent investor attention. However, they also result in more significant trading losses, primarily due to transaction costs, highlighting the potential for both beneficial and unintended consequences for investors.

Regulation and Future Research:

Given the influence of social networks on stock market reactions, the question of government regulation of social media platforms arises. Regulation is essential but should be done carefully and tailored to specific situations, as there is no one-size-fits-all solution. Future research could explore other social media platforms, news sources, economic outcomes, and policy implications or platform design choices to harness the power of social networks while mitigating potential drawbacks.

Conclusion:

Social networks play a crucial role in financial markets, shaping investor behaviour and market reactions to earnings news. Understanding their impact is essential in today's widespread online social media usage. Researchers should continue exploring social networks' role in finance, aiming to harness their power for beneficial purposes while being cautious of potential unintended consequences.

SUMMARY

This seminar discusses the impact of social networks on financial markets, focusing on the role of social networks in disseminating earnings news and the subsequent stock market reactions. Utilizing Facebook data and stock tweets messages, the researchers examine the influence of social networks on price efficiency, trading volume, and investor behaviour. The study reveals that social networks can have both beneficial and unintended consequences for investors, improving price efficiency and amplifying behavioural biases. The presenter also addresses questions about the potential need to regulate social media platforms due to their influence on stock market reactions, suggesting that regulation should be done carefully and tailored to specific situations.

 

Key Takeaways:

1. Social networks play a significant role in financial markets and can influence economic and political outcomes.

2. Researchers utilize Facebook data and stock tweets messages to study social networks' role in information dissemination and investor attention.

3. Social networks can improve price efficiency and facilitate information dissemination but may also amplify behavioural biases and propagate incorrect beliefs.

4. The influence of social networks on decision-making is context-specific and warrants further research.

5. Regulation of social media platforms is essential but should be carefully considered and tailored to individual situations.