Cross-national study on intelligence and socioeconomic development.

This thesis consists of three separate studies, all of which are empirical treatments to examine the relationship between intelligence (IQ) and socioeconomic development at the cross-country level. The first study employed the IQ data from Rindermann, Sailer, and Thompson (2009) who have IQ of a country classified into three strata, namely intellectual class, average IQ class, and non-intellectual class, which respectively represented by the 95th, 50th, and 5th percentiles of cognitive ability at the normal distribution, to examine their effects on economic growth rate, technological achievement, and crime rates. By using hierarchical multiple regression method, this study found that all IQ classes were significant on economic growth and a decrease in the crime (homicide) rate, while only the intellectual class was significant on technological achievement. The findings concluded that the national investment in human capital should benefit all classes of society, and emphasize the intellectual class for generating the technological progress.

The second study examined the impacts of psychological well-being of society (i.e., health, life satisfaction, and national peace) and globalization (i.e., economic, social, and political globalization) in influencing the effect of IQ on economic growth. By using hierarchical multiple regression method and the national average-IQ data from Meisenberg and Lynn (2011), this study found that increased globalization and life satisfaction have reduced the positive effect of IQ on economic growth, while health and national peace were non-significant on this relationship. These findings concluded that increased life satisfaction has reduced the desire for higher performance, while, in the context of globalization, there was a friction that has reduced the probability of the occurrence of positive assortative matching of cognitive skills, thereby decreasing the positive effect of IQ on economic growth.

The third study explored the relationships between socioeconomic factors and their influences on the children’s IQ. By using path analysis method and the average PISA test score (OECD, 2010, 2013) as a proxy for IQ, this study found that the decline in adult fertility rate and the increase in the children’s levels of health and schooling were significant in improving the IQ. Furthermore, the rise in educational attainment of adults and per capita income had indirect effects on IQ, through their effects on adult fertility rate decline and increased levels of children’s health and schooling. These findings concluded that a rise in IQ of a country can be achieved in the long term across generations.