ABSTRACT
Earlier quantitative assessments of the GSP can be classified into two groups. The first of these uses what may be called the ex ante approach. Estimates of the effects of tariff preferences on the beneficiaries are made on the basis of assumed values for the elasticities of the demand and supply curves and the pre-preference tariff rates and values of imports. The effects of the preferences on the donor and the non-beneficiary exporting countries are typically ignored, while quantitative restrictions on imports are often omitted from the analysis or some simplistic assumption about their effects is made.
