Présentation de Uyanga TURMUNKH, IESEG BS, Lille
**Abstract:** Why do people turn out to vote? Classical economic theory predicts that belief about own vote’s pivotality plays a key determining role in whether or not a person decides to turn out to vote. Empirical investigations, however, tend to find no evidence that believed pivotality matters for turnout. This paper examines voting decisions from a behavioral perspective, which, unlike the classical theory’s assumption of Bayesian beliefs, allows ambiguity to distort people’s beliefs about how pivotal their votes may be in deciding the outcome of an election. We empirically investigate the theoretic implications of ambiguity in the context of the U.S. Presidential Election in 2020. We detect significant and varying levels of ambiguity in people’s pivotality perceptions of their votes. By accounting for ambiguity in measurement of beliefs, we are then able to resolve the existing discord between theory and empirics with regard to the role of pivotality. Beliefs about pivotality motivate decisions to vote, but perceived ambiguity dampens the effect. Our results show the usefulness of controlling for ambiguity, especially in investigations of real-world decisions where probabilities of uncertain events are usually not known.