Replication Data for: Challenging the Manifesto Project Data Monopoly

We propose a novel approach for generating time-series for party positions as an alternative to the estimates provided by the Manifesto Project. Our approach combines multiple expert surveys from different years, filling up the missing data using a multiple imputation algorithm that uses additional information from mass surveys. We illustrate this approach by estimating time-series for eight European countries for periods up to 50 years and show that our estimates are comparable, if not superior, in richness and face validity to those of the Manifesto Project. The data can be used to explore the robustness of empirical analyses using party position data and serve as valid benchmarks for computational text scaling and crowd-sourced manual coding of party manifestos.本研究提出一种全新方法，用于生成政党立场时序数据，作为政党宣言项目（Manifesto Project）所提供估算结果的替代方案。本方法整合了不同年份的多份专家调研数据，并借助利用民众调研额外信息的多重插补算法填补缺失数据。我们通过为8个欧洲国家估算最长达50年的政党立场时序数据来演示该方法，并证实我们的估算结果在丰富性与表面效度（face validity）上，即便未超越也可与政党宣言项目的结果相媲美。本数据集可用于探究使用政党立场数据开展的实证分析的稳健性，同时可作为计算文本标度以及政党宣言众包人工编码工作的有效基准。