Agglomeration, Inequality and Economic Growth: Cross-section and panel data analysis

The effects of inequality on economic growth depend on several factors. On one hand, they depend on the time horizon considered, on the initial level of income and on its initial distribution. But, on the other hand, as growth and inequality are also uneven across space, it also seems relevant to wonder about the effects of the geographic agglomeration of economic activity. Moreover, it seems relevant to consider not only the levels of inequality and agglomeration, but also their change -their evolution within countriesand the interaction between both processes. By considering different econometric specifications and introducing different measures for agglomeration at country level, especially urbanization and urban concentration rates, this work analyzes how increasing inequality and increasing agglomeration influence economic growth depending on the level of development and on the initial distribution of income. Our results suggest that while high inequality levels are a limiting factor for long-run growth -consistent with previous literature-, increasing inequality and increasing agglomeration have the potential to enhance growth in low-income countries where income distribution remains relatively equal, but can degenerate in congestion diseconomies in high-income ones, especially if income distribution becomes too unequal.