Age data frequently display excess frequencies at round or attractive ages, such as even numbers and multiples of five. This phenomenon of age heaping has been viewed as a problem in previous research, especially in demography and epidemiology. We see it as an opportunity and propose its use as...

Age data frequently display excess frequencies at attractive numbers, such as multiples of five. We use this "age heaping" to measure cognitive ability in quantitative reasoning, or "numeracy". We construct a database of age heaping estimates with exceptional geographic and temporal coverage,...

The literature has not sufficiently engaged the emergence and expansion of the phenomenon of Slave export. This article contributes to the existing stream by examining the role of human capital or intelligence on slave exports. We postulate and justify a reasonable hypothesis that countries...

This article examines the role of cognitive ability or intelligence on slave expor ts from Africa. We test a hypothesis that countries which were endowed with higher levels of cognitive ability were more likely to experience lower levels of slave exports from Africa probably due to comparatively...

One of the most disturbing contemporary episodes in human history that has been decried globally is the recent Libyan experience of slave trade, where migrants captured end-up being sold as slaves. We contribute to the understanding of this phenomenon by investigating the role of cognitive human...

The literature has not sufficiently engaged the emergence and expansion of the phenomenon of Slave export. This article contributes to the existing stream by examining the role of human capital or intelligence on slave exports. We postulate and justify a reasonable hypothesis that countries...

This article examines the role of cognitive ability or intelligence on slave expor ts from Africa. We test a hypothesis that countries which were endowed with higher levels of cognitive ability were more likely to experience lower levels of slave exports from Africa probably due to comparatively...

One of the most disturbing contemporary episodes in human history that has been decried globally is the recent Libyan experience of slave trade, where migrants captured end-up being sold as slaves. We contribute to the understanding of this phenomenon by investigating the role of cognitive human...

We propose four arguments favoring the idea that medical effectiveness, adult longevity and height started to increase in Europe before the industrial revolution. This may have prompted households to increase their investment in human skills as a response to longer lives and initiated the...

We propose a new theory of the demographic transition based on the evidence that body development during childhood is an important predictor of adult life expectancy. Fertility, childhood development, longevity, education and income growth all result from individual decisions. Parents face a...