Measuring the strength of trade unions and identifying the privileged groups: A two-dimensional approach and its implementation

ABSTRACT Trade unions were important actors in the advanced capitalist countries until the late 1970s, but since the 1980s, union membership is declining. Whether this decline has been homogenous is crucial. Because unions may still have power and non-homogenous decline implies that some groups benefit from this power disproportionately. However, we don’t have instruments to scrutinize this dynamic properly. To fill the gap, this study develops a model that identifies privileged groups within trade unions by informing us about the relative strength of a group within trade unions, the ability of this group to use the union power, and the extent to which union members belonging to the group would advance the interests of the entire group by using this power.