Endogenous fertility, multiple growth paths, and economic convergence

"This paper extends the Cass-Koopmans optimal growth model to allow for endogenous fertility choice. It is shown that if agents choose their fertility rate, then the net rate of return on capital (marginal product of capital minus the population growth rate) may not be monotonically decreasing in capital. In this case, multiple steady states and growth paths may emerge, which can explain the persistent differentials in income between poor and rich countries, as well as the existence of development miracles and disasters. The paper provides also empirical evidence which supports the existence of multiple convergence groups and is consistent with the theoretical model."