the 1950s, output/worker in rich and poor countries generally has not converged, but those poor countries that have greatly raised their savings rates have experienced the income convergence predicted by the Solow–Swan model. As an example, output/worker in Japan, a country which was once relatively poor, has converged to the level of the rich countries. Japan experienced high growth rates after it raised its savings rates in the 1950s and 1960s, and it has experienced slowing growth of output/worker since its savings rates stabilized around 1970, as predicted by the model. The per-capita income levels of the southern states of the United States have tended to converge to the levels in the Northern states. The observed convergence in these states is also consistent with the conditional convergence concept. Whether absolute convergence between countries or regions occurs depends on whether they have similar characteristics, such as: Education policy Institutional arrangements Free markets internally, and trade policy with other countries. Additional evidence for conditional convergence comes from multivariate, cross-country regressions. Econometric analysis on Singapore and the other "East Asian Tigers" has produced the surprising result that although output per worker has been rising, almost none of their rapid growth had been due to rising per-capita productivity (they have a low "Solow residual"). See also Economic growth Endogenous growth theory Notes References Further reading van Rijckeghem Willy (1963) : The Structure of Some Macro-Economic Growth Models : a Comparison. Weltwirtschaftliches Archiv volume 91 pp. 84–100 External links Solow Model Videos - 20+ videos walking through derivation of the Solow Growth Model's Conclusions Video explanation by Marginal Revolution University Java applet where you can experiment with parameters and learn about Solow model Solow Growth Model by Fiona Maclachlan, The Wolfram Demonstrations Project. A step-by-step explanation of how to understand the Solow Model Professor José-Víctor Ríos-Rull's course at University of Minnesota Economic growth Economics models