Comparing the Performance of National Educational Systems: Inequality Versus Achievement?

We measure performance change for the educational systems of 28 countries which participated in the Trends in International Mathematics and Science Study in years 2007 and 2011 for eighth grade basic education students. We consider simultaneously variables related to academic achievement and inequality in the discipline of mathematics. From a methodological point of view, we use the global Malmquist-Luenberger productivity index due to the presence of bad outputs. To the best of our knowledge, this methodology had not been applied previously in the field of education despite these desirable which are particularly useful in this field. Results indicate that the countries participating in the study not only chose different paths to improve their educational performance but, in addition, results varied remarkably among them. They also suggest that, on average, educational performance deteriorated between 2007 and 2011, although we also found (successful) efforts in several countries to improve equality.