The Unassuming Economist

From a paper by Thanh Nguyen, Son Nghiem, and Anh-Tuan Doan:

“The convergence tests showed no overall convergence but revealed convergence clubs for each factor. Granger causality tests indicated short-run bi-directional relationships between the variables. Long-run panel regression analysis confirmed that technological progress significantly improves per capita income and energy diversification. Additionally, it revealed bi-directional relationships between energy diversification and financial development, a uni-directional relationship from financial development to per capita income and a U-shaped effect of per capita income on energy diversification, with a turning point at $67,112.8 per year.”