This paper seeks to identify the determinants of the successes (government entry) of small political parties in 21 European states. Although the term small party is used quite regularly the borders between small, medium or large parties are not precisely delineated. To overcome this problem, I propose an original mathematical formula to select the group of 26 small parties based on the same criteria in 21 European states. Having this sample, I analyse all coalition cabinets to which these parties were invited as the junior partners. The main goal in this paper is to explain the causes of these parties' presence in the governments and explore the determinants of the portfolio allocations by combining quantitative (i.e. Banzhaf Power Index) and qualitative (ideological distance) measures. Some of the conclusions confirm previous findings (disproportional portfolio allocation which favours small parties) and some only partially overlap with the conclusions drawn in the previous studies (the relation between the number of potential/ alternative collaborators and the likelihood that the small party becomes the coalition member). This study deals with the cases from Central and East European States, and Western Europe.
Piotr Sula (Wed,) studied this question.