ارائه پیشنهادات در مورد اثرات موافقت نامه های نظری تجاری منطقه ای چند وقت است؟

This paper uses computational techniques to assess whether or not various propositions that have been advanced as plausible in the literature on regional trade agreements may actually hold. The idea is to make probabilistic statements as to whether propositions of interest might hold, rather than to restrict assumptions so they unambiguously hold. Our aim is to blend theory and numerical simulation and go beyond the ambiguous analytically derived propositions that dominate the theoretical literature so as to assess the likelihood of propositions holding for particular model specifications.

In this paper, we generate repeated model solutions for alternative numerical specifications of a simple (few countries and commodities) general equilibrium trade model so as to map out the extent of the parameter space for which each of a series of propositions regarding customs unions is true.1 The idea is to blend theory and numerical simulation, in contrast to theoretical work in this area which sets out assumptions under which propositions unambiguously hold, and demonstrates their validity using analytical techniques. Here we take a different approach of trying to determine the frequency with which various results hold so as to obtain an indication of which statements are more likely to hold and which not.

Results in Table 3 indicate that some propositions hold in a clear majority of computed cases (Proposition 6, whether a CU improves the members' terms of trade relative to Nash) while others hold less frequently. For instance, both members benefit by forming a customs union relative to the three-country Nash outcome in only 48% of the cases. A customs union improves world welfare relative to a Nash equilibrium in 76% of computed cases. Customs unions result in higher external tariffs for member countries compared to Nash in 72% of cases. Customs unions lead to more international trade for member countries (relative to Nash) 87% of the time. At the other end of the spectrum only in 4% of the cases are customs unions a “stepping stone” to free trade. We next discuss each of the results in more detail.