This paper shows that governments have no incentive to introduce non-tariff barriers when they are free to set tariffs but they do when tariffs are determined cooperatively. We then show three results. First, with trade liberalization, there is a progression from u sing tariffs only to quotas,...

Standard media economics models imply that increased platform competition decreases ad levels and that mergers reduce per-viewer ad prices. The empirical evidence, however, is mixed. We attribute the theoretical predictions to the combined assumptions that there is no advertising congestion and...