In this paper, we examine the issue of b - convergence of per-capita GDP in the ECOWAS countries under the assumption of parameter heterogeneity. We apply panel data techniques to an error-correction model that allow us to take into account latent heterogeneities across the countries. In...

This paper provides empirical evidence that there is no absolute convergence between the GDP per capita of the developing countries since 1950. Relying upon recent econometric methodologies (nonstationary long-memory models, wavelet models and time-varying factor representation models), we show...