Seemingly unreleated regression equations and an application to export function of Turkey

In this study; Seemingly Unrelated Regression Equations(SURE) which forms the error terms related equation system is examined in order to show its efficient over the Ordinary Least Square Method (OLS). Towards this aim first of all a brief introduction about OLS is given and the Generalized Least Square method that constitutes the main part of SURE is also examined. After that SURE method's definition, spesifications and substraction of its estimator are shown and gain in the efficiency related to OLS method is proved. In empirical analysis; Turkey's exports to 18 OECD countries between 1982-1995 was estimated by using OLS and SURE methods and found out that the estimators of SURE method were more efficient. Conclusively, by applying SURE method to the models; which seems to be independent but in which there exists a relation between its error terms of equation, it has been proved that empirical and teoric results of SURE estimator is more efficient than OLS estimator.