Does HDIs level sustainable during 1999/2018 across cross-nations? An application of bootstrap quantile regression approach

Potential growth and overall economic development across nations since 1990s till 2018 is functioning as a 'wake-up' call for researchers and policy makers to process for investigation the phenomenon of HDI convergence globally via two framework: σ- and unconditional β- convergence. A proper investigation of such knowledge is of utmost important for regulators of economies, suggesting whether the difference in HDI level across natons has narrowed, including the period of global recession (2007/09). The empirical evidence is analyzed from different methods that act in a complementary way: i) bootstrap quantile regression approach in static panel framework, which allows the assumption of nonlinearities, especially for those groups that have shared a common path in terms of economic development while estimating the convergence results. ii) pooled OLS model, which seek to examine the soundness of the evaluated convergence results and confirmed the validity of our core applied model. All methods revealed strong evidences of unconditional β- convergence for all HDI groups, reflecting all classified HDI groups had potential to increase their tendency toward convergence. This is mainly driven by both the slower forward mobility with the less developed nations and faster backward mobility with the more developed nations. The σ- convergence estimates provides further insights and suggests that the formation and comprising of multiple convergence HDI clusters is a salient feature of reduction in inequality and dispersion across medium and lower nations.