CORE Discussion Paper #2009/38 Urban Concentration and Economic Growth: checking for specific regional effects ∗ Alain PHOLO BALA † May 2009 Abstract By using a semiparametric specification, we examine the impact of urban concen- tration in economic growth on different groups of countries that we classify according to a geographical criterion or according to their level of development. Facing a signif- icant proportion of missing data, we handle that problem with a multiple imputation algorithm as advised in the statistical litterature. Therefore using a Bayesian esti- mation we obtain parametric coefficients and non parametric curves. Then we may perform Yatchew’s tests of equality of non parametric effects to check out if the model specification is the same in the different groups of countries. Keywords: urban primacy; economic growth; missing data; imputation; semipara- metric estimation JEL Classification: C14; C30; C49; R15 * We thank Luc Bauwens, Dominique Peeters and Jacques Thisse for very detailed comments on a previous version of this paper. We also thank Fausto Galli, Wilfried Koch for helpful comments and discussions. The usual disclaimer applies. † CORE, 34 Voie du Roman Pays 1348 Louvain-La-Neuve, Belgium. Office: (+32)10474353. Fax: (+32)10474301. E-mail: Alain.PholoBala@uclouvain.be. 1