A Scaling Model for Estimating Time-Series Party Positions from Texts

  title={A Scaling Model for Estimating Time-Series Party Positions from Texts},
  author={Jonathan B. Slapin and Sven-Oliver Proksch},
  journal={American Journal of Political Science},
However, existing text-based methods face challenges in producing valid and reliable time-series data. This article proposes a scaling algorithm called WORDFISH to estimate policy positions based on word frequencies in texts. The technique allows researchers to locate parties in one or multiple elections. We demonstrate the algorithm by estimating the positions of German political parties from 1990 to 2005 using word frequencies in party manifestos. The extracted positions reflect changes in… 

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