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U.S.A."],"published-print":{"date-parts":[[2018,9,11]]},"abstract":"<jats:title>Significance<\/jats:title>\n                  <jats:p>Social media sites are often blamed for exacerbating political polarization by creating \u201cecho chambers\u201d that prevent people from being exposed to information that contradicts their preexisting beliefs. We conducted a field experiment that offered a large group of Democrats and Republicans financial compensation to follow bots that retweeted messages by elected officials and opinion leaders with opposing political views. Republican participants expressed substantially more conservative views after following a liberal Twitter bot, whereas Democrats\u2019 attitudes became slightly more liberal after following a conservative Twitter bot\u2014although this effect was not statistically significant. 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