This paper shows that the welfare dominance of ad valorem over unit taxes under imperfect competition, extends to the Dixit-Stiglitz framework with differentiated products, entry and love of variety. This contrasts against findings by Anderson et al. (J Public Econ, 2001) made in a similar...

This paper investigates the effect of economic integration on the ability of firms to maintain a collusive understanding about staying out of each other's markets. The paper distinguishes among different types of trade costs: ad valorem, unit, fixed. It is shown that for a sufficient reduction...

The ad valorem versus unit taxes debate has traditionally emphasized tax yield. For this criterion, ad valorem taxes outperform unit taxes in terms of welfare for a wide range of imperfect competition settings, including Dixit-Stiglitz monopolistic competition. Yet, in a number of policy fields,...

Environmental policies frequently target the ratio of dirty to green output within the same industry. To achieve such targets the green sector may be subsidised or the dirty sector be taxed. This paper shows that in a monopolistic competition setting the two policy instruments have different...