Trade unions are often argued to cause allocative inefficiencies and to lower welfare. We analyze whether this evaluation is also justified in a Cournot-oligopoly with free but costly entry. If input markets are competitive and output per firm declines with the number of firms (business...

If input markets are competitive and output per firm declines with the number of firms (business stealing effect), there will be excessive entry into a Cournot oligopoly for a homogeneous commodity. However, input markets are often imperfectly competitive and the price of labor is determined by...

How does an increase in unionization costs, i.e. costs which arise when workers are organized by a union, affect the productivity distribution of active firms, wage inequality and welfare? In this paper, we build a model with costly, endogenous unionization, heterogeneous firms as well as free...

What are the effects of firm- and sector-level trade unions on unemployment and aggregate output if individuals have rent-sharing motives? To answer this question, we extend a Melitz-type model to unionized labor markets. Because individual rent-sharing motives are only taken into account and...