Influence of country‘s area on growth - implications

Possible improvement: inclusion of the share of agricultural production in GDP
Possible improvement: inclusion of population (or population density) growth -> empirical investigation of which countries are stuck in Malthusian trap (population growth exceeds output growth until starvation „checks“ population growth; see Begg, Fischer, Dornbusch (1997), ch. 30)

Possible improvement: inclusion of the share of agricultural production in GDP