Convergence or confusion? A study of world economic growth

This paper takes a closer look at the typical growth convergence regression of Barro (1991), Mankiw, Romer and Weil (1992), Sala-i-Martin (1996), and others. By interpreting the two components of the regression coefi¬ cient separately, i.e. the correlation coefficient and the ratio of standard deviations, we distinguish between "time-series" convergence and "cross-section" convergence, and consequently the relationship between I²âˆ’ and Iƒâˆ’convergence. And, using data from the latest Penn World Table database (version 9.1), we investigate the convergence or the lack-of-convergence in samples of countries representing the “World†, OECD and Sub-Saharan Africa. The implications of this study for the neoclassical growth model are also discussed.