What does the vertical axis of the Kuznets curve depict (mathematically)? I do not understand what does the word "inequality" means on the vertical axis of the Kuznets curve. Can someone please explain?
Kuznet talked about income inequality. In this context it is often measured by the Gini coefficient or the Kuznet ratio, but basically any measure of income inequality would do, since Kuznet's hypothesis is merely a qualitative one.