Analýza vlivu sentimentu investorů na dynamiku ceny akcií firmy Gamestop

This bachelor’s thesis examines the impact of investor sentiment on the social media platform Reddit on the stock price dynamics of GameStop (GME) during the 2021 short squeeze event. Grounded in behavioral finance theories, particularly herd behavior and the influence of emotions and cognitive biases on investment decisions, the study analy zes over 680,000 posts and comments from seven relevant subreddits (e.g., r/wallstreet bets) collected between December 2020 and July 2021. Sentiment was assessed using the VADER tool and a custom keyword-based method. Statistical analyses, including corre lation, multiple regression, and the Chow test, revealed a weak correlation between weighted sentiment and GME stock prices but a strong correlation between the number of posts and stock price before the February 1, 2021 structural break. The findings suggest that social activity on Reddit, rather than sentiment alone, significantly contributed to mobilizing retail investors and driving price volatility. Thesis highlights the growing role of social media in shaping financial markets in the digital era and limitations of sentiment analysis in predicting stock prices, contributing to the discourse on modern market ano malies.