Speed of Convergence in a Malthusian World: Weak or Strong Homeostasis?

Standard Malthusian models predict that a productivity or population shock modify income per capita in the short run. In the long run, however, population pressures make income per capita gradually come back to its steady state. I investigate the duration of this short-run fluctuation, estimating the speed of convergence of Malthusian economies to their GDP per capita and population steady-states. To do so, I first build and calibrate a Malthusian model capturing explicitly the idea that marriages are postponed (advanced) and fertility potential of couples reduced (augmented) during depressions (expansions). I then also run β-convergence regressions on historical panel data. I find consistent evidence of weak homeostasis, with a half-life of about one century. It implies that early modern data may display high persistence without necessarily rejecting the Malthusian hypothesis.