 Hunt, due to there being far more data available, Rindermann's analysis was more reliable than those by Lynn and Vanhanen.By measuring the relationship between educational data and social well-being over time, Rindermann also performed a causal analysis, finding that nations investing in education leads to increased well-being later on.Some of Rindermann's work has concentrated on the "smart fraction" theory, which states that the prosperity and performance of a society depends on the proportion of the population that is above a particular threshold of intelligence, with the threshold point being well above the general median intelligence level in most societies.