Bhanupong Nidhiprabha accused the authors of being lost in the Mincer wage equation, which was originally used to identify the returns to education, which in this paper only explains 34 percent of wage variation. Because of the low explanatory power, Nidhiprabha suggested that the authors should tackle other issues they are silent on, such as the influence of migration and urbanization on developments in China's wage inequality. More generally, Nidhiprabha asked the authors to provide more information on wage determinants, whether they work from a supply and demand framework, or work to tie wages to worker value marginal product. In the latter case, tied to the evolution of worker value marginal product, Nidhiprabha indicated that the differential could be decomposed to reveal elements such as worker learning-by-doing tied to experience.
Toshihiro Okubo pressed the authors to focus on sample selection issues that may influence the data from the surveys over...