Extracting valid and reliable measures of party positions is a core research activity in the field of party politics. In this paper we asses different approaches to positioning parties in the political space with a special focus on the 2014 elections to the European Parliament (EP). At a broad level, we distinguish between top-down approaches that are based on expert judgements and bottom-up approaches that draw on respondent data. Within each approach we contrast different methods for estimating party posistions. For example, within the top-down approach we compare conventional expert surveys to iterative expert coding and among bottom-up approaches we contrast subjective placements of parties by respondents with estimates derived from the ideological profile of party supporters. Finally, we empirically evaluate the validity of all the measures by looking at the degree to which they explain membership to party groupings in the EP.
