All economists are well aware of the Keynesian macro-multiplier, but many are (much) less aware of its essential generalization to a multi-industry setting due to Japanese economist Ken'ichi Miyazawa (1925-2010). In this essay, jointly written with Geoffrey Hewings, we apply Miyazawa’s concepts of "interrelational income multiplier" and "matrix multiplier of income formation" within a global multi-regional input-output (IO) framework. In general, one of the notable features of Miyazawa's multiplier analysis is its usefulness in examining and understanding the (heterogenous) impacts of households' diverse socio-demographic characteristics, such as income, place of residence, age, education or activity status.
Why are some countries much poorer than others? Why does the gap between rich and poor countries remain wide over a long period of time, irrespective of e.g. technological advances and economies' openness? Various explanations are given in the literature, wherein some philosophers, economists and other scientists emphasize the role of Nature (i.e. physical and geographical environment), while others consider man-made factors shaping human incentives as more fundamental causes of countries' (under)development. Below the main explanations (or hypotheses) of comparative economic growth are discussed, particularly focusing on the role of institutions in the process of economic development.