“…Together with σ -convergence, 3 these concepts have been criticized for several econometric problems they bring about, like Galton's fallacy problem, and their inadequacy to explain economic polarization, persistent poverty and clustering (Quah, 1993). In contrast, the concepts of convergence clubs (Durlauf and Johnson, 1995;Chatterji, 1992;Quah, 1996) and coreperiphery (Krugman, 1991a(Krugman, , 1991bFujita et al, 1999) are compatible with the existence of multiple, locally stable steady state equilibria that are more relevant in the European regional case.…”