Revisiting the left cabinet share: How to measure the partisan profile of governments in welfare state research

Measuring the power of the political left with the ‘share of social democratic cabinet seats’ is the gold standard in the literature on partisan effects. We argue that this measure of left power suffers from conceptual ambiguity and propose an alternative approach to measure the ideological orientation of governments based on their power in cabinets and data on party positions. We see several shortcomings of the traditional measure: the social democratic cabinet share neglects the fact that parties’ ideological profiles differ across countries and have significantly changed over recent decades. Also, specific policy measures of party preferences are often more appropriate to gauge the government’s position than relying on highly aggregated left/right measures.In addition, the social democratic cabinet share does not take into account the impact of coalition partners, cabinet decision making and the possibility of minority governments relying on parliamentary support outside the cabinet on the ability of parties to implement the social policies.

After discussing the reasons for the conceptual ambiguity of existing indicators for the power of the left, we present alternative measures for the ideological orientation of the government based on the composition of cabinets and different information about party positions. We demonstrate how these measures can be combined to a single indicator that takes into account both the ideological position of governing parties in a particular policy domain and their power to affect cabinet decisions. We critically discuss the availability and merits of data on party positions and cabinet compositions and provide recommendations for constructing measures in welfare state research.