Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We study whether social media can amplify antiminority sentiment with a focus on Donald Trump's political rise. Using an instrumental variable strategy based on Twitter's early adopters at the South by Southwest festival in 2007, we find that higher Twitter use in a county is associated with a sizeable increase in anti-Muslim hate crimes after the 2016 presidential primaries. Trump's tweets about Muslims predict increases in xenophobic tweets by his followers, cable news mentions of Muslims, and hate crimes on the following days. These results suggest that social media content can affect real-life outcomes.