Measuring Interest Group Influence Using Quantitative Text Analysis

The analysis of interest group influence is crucial in order to explain policy outcomes and to assess the democratic legitimacy of the European Union. However, owing to methodological difficulties in operationalizing influence, only few have studied it. This article therefore proposes a new approach to the measurement of influence, drawing on quantitative text analysis. By comparing interest groups’ policy positions with the final policy output, one can draw conclusions about the winners and losers of the decision-making process. In order to examine the applicability of text analysis, a case study is presented comparing hand-coding, WORDSCORES and Wordfish. The results correlate highly and text analysis proves to be a powerful tool to measure interest groups’ policy positions, paving the way for the large-scale analysis of interest group influence.