Can we have growth when population is stagnant? Testing linear growth rate formulas of non-scale endogenous growth models
Thomas Ziesemer
#2018-044
Endogenous growth theory has produced formulas for steady-state growth
rates of income per capita, which are linear in the growth rate of the
population. Depending on the details of the models, slopes and
intercepts are positive, zero or negative. Empirical tests have taken
over the assumption of exogenous population growth from the theoretical
models and have mostly not distinguished steady-state results from
transitional growth. In contrast, (i) we assume that there is the
possibility of two-way causality as in unified growth theory, and (ii)
we capture the steady-state property by a long-term relation in a series
of vector-error-correction models, allowing (iii) successively for more
heterogeneity. The average slope and intercepts of the growth equations
are positive in this setting but less significant or even negative when
allowing for heterogeneity. Intercepts are then positive for a majority
of countries, zero for five or six countries, and perhaps negative for
at most two countries. Results therefore favour fully- over
semi-endogenous growth with and without slope homogeneity. The more
frequent case is that long-run growth can remain positive if population
stops growing.
JEL Classification: C33, O47
Keywords: Endogenous growth, population growth, panel times series estimation