The article examines how well European regions are doing economically by calculating total factor productivity. They use a panel cointegration approach to compare different economies and see if there are scale economies or market issues. This method also deals with non-stationarity problems in the data. By testing for unit roots and cointegration, the researchers can avoid misleading results and find long-term relationships in the data. The evidence suggests that unit roots are common, so cointegration is necessary for accurate modeling.