productivity: a new technology is "more risky" and more productive on average. In this context, the adoption of the new technology from a low level of income (close to subsistence) generates a gradual increase in the investment to output ratio.

Consider the following facts. In 1950, the richest countries attained an average of 8 years of schooling whereas the poorest countries 1.3 years, a large 6-fold difference. By 2005, the difference in schooling declined to 2-fold because schooling increased faster in poor than in rich countries....

Low sex ratios are often equated with unfavorable marriage prospects for women, but in France after World War 1, the marriage probability of single females rose 50%, despite a massive drop in the male/female ratio. We conjecture that the war-time birth-rate bust induced an abnormal postwar...

The decision to look for a job, as well as some measures of income inequality, are closely connected with the living arrangements people choose and, therefore, are important to policymakers.

What drove western population growth in the U.S. during the 19th century? The facts are: (i) The birth ratio was higher in the West than in the East. Both exhibited a secular decline. (ii) Between 1800 and 1810 net migration accounted for 88% of the rate of population growth in the northwest...

The U.S. economic development in the nineteenth century was characterized by the westward movement of population and the accumulation of productive land in the West. This paper presents a model of migration and land improvement to identify the quantitatively important forces driving this...

During the first half of the 20th century the workweek in the United States declined, and the distribution of hours across wage deciles narrowed. At the same time, the distribution of wages narrowed too. The hypothesis proposed is (i) Households have access to an increasing number of leisure...

Between 1940 and 2000 there has been a substantial increase of educational attainment in the United States. What caused this trend? We develop a model of human capital accumulation that features a non-degenerate distribution of educational attainment in the population. We use this framework to...

During World War I (1914–1918) the birth rates of countries such as France, Germany, the U.K., Belgium and Italy declined by almost 50 percent. The age structure of these countries’ populations were significantly affected for the duration of the 20th century. In France, where the population...

The size of the Social Security program as a percentage of output has increased continuously since its inception. The main expansion has been on the extensive margin (number of individuals under the program), rather than on the intensive margin (benefits per old). Most of the increase was not...