I show that in a conventional Ramsey model, between one-fourth and one-half of the global income distribution can be explained by a single factor: The effect of large, persistent differences in national average IQ on the private marginal product of labor. Thus, differences in national average IQ...

Human capital plays an important role in the theory of economic growth, but it has been difficult to measure this abstract concept. We survey the psychological literature on cross-cultural IQ tests, and conclude that modern intelligence tests are well-suited for measuring an important form of a...

I show that in a conventional Ramsey model, between one-fourth and one- half of income differences across countries can be explained by a single factor: The steady-state effect of large, persistent differences in national average IQ on worker productivity. These differences in cognitive...

This paper constructs the probability space underlying the random variable of any time dependent econometric specification. The construction links concrete economic activity, both perceived and recorded, and econometric formulations. Furthermore, it is argued that the probability events...

This paper constructs the probability space underlying the random variable of any time dependent econometric specification. The construction links concrete economic activity, both perceived and recorded, and econometric formulations. Furthermore, it is argued that the probability events...