Understanding Voters' Preferences: How the Electorate's Complexity Affects Prediction Accuracy and Wishful Thinking among Politicians with Respect to Election Outcomes
基于498名比利时地方政治家的调查，研究选民规模与异质性如何影响政治家预测本党选举结果的准确性及一厢情愿偏差，发现小选区政治家更准确、偏差更小，为分权治理提供依据。
Summary Models of political decision making often assume that politicians are fully informed on voters' preferences. Still, while they may be privileged witnesses of the democratic process, real‐world politicians typically act upon imperfect information. Using a large scale survey among (498) Belgian local politicians we analyse whether and to what extent politicians are informed on public opinion. More precisely, we analyse their predictions of the electoral result of their own party in an upcoming election. The focus is on the impact of the electorate's complexity on this prediction accuracy. Complexity is defined in terms of the size and heterogeneity of the electorate. Complexity is found to affect both cognitive (prediction accuracy becomes smaller) and affective (predictions are biased through wishful thinking) processes underlying the politician's prediction. The empirical results show that smaller electorates have better informed politicians (with smaller prediction errors and less subject to wishful thinking), offering a case for decentralized government. Heterogeneity has a bearing on prediction accuracy and wishful thinking. Interestingly, the effects differ between politicians in power and those in opposition.