Introduction
According to the “wisdom of crowds” (WOC) principle, “under the right circumstances, groups are remarkably intelligent, and are often smarter than the smartest people in them. […] Even if most of the people within a group are not especially well-informed or rational, it can still reach a collectively wise decision” (Surowiecki, 2004, pp. xiii–xiv). The benefits of collective judgment have already been demonstrated multiple times in the fields of psychology, statistics, and management science (see, e.g., Clemen, 1989; Davis-Stober, Budescu, Dana, & Broomell, 2014; Dunning, 2007, pp. 84–86; Stewart, 2001, pp. 95–96; Yaniv, 2004). In political science more specifically, the WOC principle has been invoked as the main explanation underlying the accuracy of voters’ collective expectations about electoral outcomes. A number of studies in the United States, the United Kingdom, and Canada have shown that most citizens were able to correctly predict which party or candidate would win in local, regional, or national elections and that the aggregation of individual estimates increased the likelihood of a correct forecast (see, for example, Graefe, 2014; Lewis-Beck & Stegmaier, 2011; Miller, Wang, Kulkarni, Poor, & Osherson, 2012; Murr, 2011, 2015, 2016; Temporão, Dufresne, Savoie, & van der Linden, 2019). In other words, the proportion of correctly predicted outcomes was always higher than the proportion of correct individual forecasts.