Mistakes, Overconfidence, and the Effect of Sharing on Detecting Lies

Mistakes and overconfidence in detecting lies could help spread. Participants our experiments observe videos which senders either tell the truth or lie, are incentivized to distinguish between them. We find that participants fail detect lies, but overconfident about their ability do so. use these findings study determinants of sharing its effect on lie detection, finding even when share truthful videos, more likely lies. Moreover, receivers believe shared videos. Combined, tendency increases with sharing. (JEL C91, D83, D91, L82)