Combining strengths of methods of party positioning to counter their weaknesses: the development of a new methodology to calibrate parties on issues and ideological dimensions

In this paper we review various methods of party positioning on issues and abstract political dimensions and describe the method that has been developed specifically for the Dutch voting advice application Kieskompas (Election Compass). Basically there are five methods for positioning political parties on political issues and on deeper-lying conflict dimensions: (a) expert surveys (b) voter surveys, (c) party elite surveys, (d) on the basis of roll-call behaviour (e) placements based on manifesto coding (either hand coded or by computer-based calibration). After reviewing the strengths and weaknesses of the various methods, we argue that combining expert placements with text-based calibration (using party manifestos) results in an improved methodology to position political parties on issues and bipolar political dimensions. This new methodology, that was developed for the Voting Advice Application Kieskompas, combines a text-based expert judgement, party-manifesto coding (including computer-based search techniques) and a self-placement by political parties. This process increases the validity and reliability of estimating party positions on political issues.