This paper compares the welfare effects of ad valorem and per unit commodity taxation, in a model of oligopolistic interaction. Our main result is that, when the number of consumers is sufficiently high, per unit taxes welfare dominate ad valorem taxes.

This contribution investigates the effectiveness and welfare implications of fiscal policies in a context of multilateral trade, when traders behave strategically. The present approach deals simultaneously with two aspects of fiscal policies: collecting resources for redistributive purposes and...