Replication Data for: Strategic ambiguity of party positions in multiparty competition

Party competition is largely about making policy promises to voters. We argue that the clarity of the expressed policy position may be equally important. If blurred messages towards different audiences and therefore ambiguous positions can attract votes from different groups, parties have incentives to present ambiguous rather than clear-cut policy platforms. We present a formal model of multiparty competition with stochastic voting where party leaders make strategic choices on both the position and the level of ambiguity of their platforms. Leaders respond to the demands of two principals, the general public and party core constituencies. We derive two hypothesis on the location and ambiguity of party platforms and provide initial tests of these hypotheses in a comparative setting in 14 Western European democracies gathering data on voter and party left-right positions from Eurobarometer surveys and electoral manifestos. Ambiguity of party profiles is estimated using a variant of Wordscores on a newly established dataset of electoral manifestos. We find that platforms become more ambiguous as the preferences of the two principals diverge. Our findings imply that ambiguity can be a winning strategy for parties, especially in settings with strong partisan lines.政党竞争在很大程度上围绕向选民作出政策承诺展开。本文认为，所表达的政策立场的清晰度或许同等重要。若政党向不同受众传递模糊信息，进而形成模糊的政策立场，便能吸引不同群体的选票，那么政党便有动机采取模糊而非明确的政策纲领。本文构建了一个包含随机投票行为的多党竞争正式模型，其中政党领袖会在纲领的立场与模糊程度两个维度做出策略性选择。领袖需要回应两类委托人的诉求：普通公众与政党核心选民。本文推导出两条关于政党纲领的立场与模糊程度的假说，并在14个西欧民主国家的比较框架下对这些假说进行了初步检验：研究数据取自欧洲晴雨表（Eurobarometer）调查与选举纲领，涵盖选民与政党的左右翼立场信息。政党形象的模糊程度通过改编自词得分（Wordscores）的方法，在全新构建的选举纲领数据集上完成估算。研究发现，随着两类委托人的偏好分歧加剧，政党纲领会变得愈发模糊。本研究结果表明，模糊策略对政党而言或是制胜之道，尤其在存在强烈党派分野的场景中。