Modeling with Piecewise Regression of Ratios of Export to Import

Exportand import constitute a country’s foreign trade. assessment can be made about the country’s economic situation by examining foreign trade statistics. one of thes estatistics is the ratio of export to import. in this study, annual changes in ratios of export to import of turkey between the years 1923-2010 were examined with piece wise regression. examining the distribution chart of data, ratios of export to import show a wavy distribution between the years 1923-2010. in models where the distribution is wavy, it is more advantegous to use piece wise regression rather than a single model. in this study, the distribution was divided into three parts and all the parts were analyzed with three different models, namely piece wise linear, quadratic and cubic models. it was aimed to determine the best fitting model.