Heroes, just for one day: The impact of Donald Trump's tweets on stock prices

We analyze the effect of Donald Trump’s tweets on individual stock returns. We use intraday (minute-by-minute) data in order to uncover causal effects of the tweets on prices and trading activity. We find that the tweets cause increased trading activity but do not have lasting effects on stock prices. We also find evidence of abnormal returns, increased trading volume and increased investor attention before the tweets. This finding is consistent with Donald Trump’s tweets not providing new information but rather being comments on events that happened, and already attracted investor attention, before the tweet