Does Twitter happiness predict bullish markets? A study of the US stock markets

The evolving literature on using Twitter to capture investor sentiment suggests that stock market performance is linearly associated with Twitter's public mood. We investigate whether investor sentiment determined by the Twitter sentiment index (TSI) has a nonlinear predictive power for stock market behaviour. Using a dataset of seven US stock markets, we apply the cointegration techniques to show the relationship between Twitter sentiment and stock market behaviour. The results suggest a dynamic nonlinear cointegrating relationship. During the short run, Twitter happiness has a substantial effect on stock market indices, while in the long run, it has a moderating effect. Twitter happiness has a dominant effect on the US stock market indices than unhappy Twitter. These results highlight Twitter's growing role in predicting the stock market behaviour and show that the TSI acts as a better predictor of investor sentiment.