Causes and consequences of expectation trajectories: "high" on optimism in a public ballot initiative

Although expectations are key theoretical antecedents of emotion and behavior, expectations are typically examined as static properties without deep consideration of their temporal dynamics. We surveyed residents of California over five time points, during the month preceding a public ballot initiative on cannabis legalization (California Proposition 19) and after the election, to examine both the causes and the consequences of residents' expectation trajectories regarding the vote's outcome. Our results point to the importance of changes in individuals' expectations over time. Specifically, well-informed voters were likely to lower their expectations regarding the measure's passage as the vote neared, in line with polling results, but being informed about the initiative had less impact on expectation trajectories among voters who favored the measure than among those who opposed it. Furthermore, supporters who maintained their optimism about the initiative's outcome over time were more likely to vote and were more disappointed following the measure's failure, compared with supporters who became more pessimistic. The findings suggest that temporal changes in people's optimism and expectations play a unique role in social behavior.