Does fake news affect voting behaviour?
利用意大利特伦蒂诺-上阿迪杰地区德语和意大利语选民的历史差异，研究假新闻对2018年意大利选举中民粹主义政党得票率的影响，发现假新闻助长民粹主义但非主因。
We study the impact of fake news on votes for populist parties in the Italian elections of 2018. Our empirical strategy exploits the historical variation in Italian-speaking and German-speaking voters in the Italian region of Trentino Alto-Adige/Südtirol as an exogenous source of assignment to fake news exposure. Using municipal data, we compare the effect of exposure to fake news on the vote for populist parties in the 2013 and 2018 elections. To do so, we introduce a novel indicator of populism using text mining on the Facebook posts of Italian parties before the elections. Our findings support the view that exposure to fake news favours populist parties regardless of prior support for populist parties, but also that fake news alone cannot explain most of the growth in populism.