Trump’s fake news and stock market returns
研究发现特朗普总统任期内的假新闻数量与美国股市当日回报正相关，但随后几天会反转，表明假新闻对市场有短期影响。
We use a novel database that identifies allegedly Donald Trump’s fake news during his presidency. We find that the number of daily fake news is positively related to contemporaneous US stock market returns. Fake news is typically positively biased in our context, increasing stock returns in the short term. We invalidate alternate explanations of the main relation, such as the notion that newly arrived information drives the relation. The mechanism of the relationship is the source used and the reliability of the fake news. Fake news matters to the extent that participants believe it is true. This positive relation reverses over the following days, indicating some evidence of correction. Overall, we find that a politician’s fake news influences financial markets temporarily.