Whether or not the marginal product of capital (MPK) differs across countries is a question that keeps coming up in … discussions of comparative economic development and patterns of capital flows. Attempts to provide an empirical answer to this … countries. However, the financial rate of return from investing in physical capital is not much higher in poor countries, so …

cross-country income variance can be attributed to differences in (physical and human) capital, and how much to differences … in the efficiency with which capital is used?" Hence, it does for the cross-section what growth accounting does in the … time series. The current consensus is that efficiency is at least as important as capital in explaining income differences …