The effect of social media and internet forums contents on the stock market

This study examines the effects of social media and internet forum posts on the market for the stocks traded on Borsa Istanbul between 2018 and 2022 and identified as manipulated by the CMB (Capital Markets Board of Türkiye). In the study, Twitter and Investing.com posts about these stocks are analyzed and a Turkish finance sentiment dictionary is created to analyze the sentiment of these posts and convert them into numerical data. In the sentiment dictionary, in addition to the traditional classification of positive, neutral, and negative categories, the category of "suspicious" was also defined to show the impact of speculative and manipulative posts. The Panel Quantile Regression Method then shows that social media internet forum activity has different effects in different market conditions (bear, normal and bull markets) and at different trading volume levels, but the positive effect of positive and suspicious content increases in the bull market and at high trading volume. The results suggest that during bull market conditions, social media activity increases investors' optimism and confidence levels, encouraging herd behavior and speculative behavior. In periods of low returns and trading volume, however, the effects of social media posts are more limited and investors tend to avoid losses during these periods. The results suggest that social media content has a significant impact on market dynamics and can significantly influence investor decisions.