Education, segregation and marital sorting: theory and an application to the UK

This paper presents a model of the intergenerational transmission of education and marital sorting. Parents matter both because of their household income and because their human capital determines the distribution of a child's disutility from making an effort to become skilled. We show that an increase in segregation has potentially ambiguous effects on the proportion of individuals that become skilled in the steady state, and hence on marital sorting, the personal and household income distribution, and welfare. We calibrate the steady state of our model to UK statistics. We find that an increase in the correlation of spouses in their years of education will bring about a small increase in the proportion of skilled individuals when the relative supply of skilled individuals is variable at the family level and a decrease when this supply is fixed. Ex-ante utility (of an unborn individual) increases in the first case and decreases in the second. The welfare effect of increased sorting is negative for unskilled individuals and positive for skilled individuals. Increased segregation always leads to an increase in welfare inequality between skilled and unskilled individuals.     

AIDS mortality and its effect on the labor market: Evidence from South Africa

This paper investigates how HIV/AIDS has impacted the labor market in South Africa, focusing on its effect on wages and employment. This is done by matching individual level data with group specific cumulative AIDS mortality rates. Exploiting the panel nature of the data, I remove individuals whose productivity is most likely impacted by HIV/AIDS, and find evidence that cumulative AIDS mortality has led to reductions in wages of between 3 and 6% for the African population group (Black South Africans). Furthermore, I also find evidence that the epidemic has lowered employment in South Africa. This result is concentrated among those with the lowest levels of education and employment. Although not large in magnitude, these effects are widespread across a significant portion of the population, contributing to a substantial loss of income throughout the South African economy.     

Why is child labor illegal?

We present a theory of the emergence of laws restricting child labor or imposing mandatory education that is consistent with the fact that poor parents tend to oppose such laws. We find that if altruistic parents are unable to commit to educating their children, child-labor laws can increase the welfare of higher-income parents in an ex ante sense. On the basis of an empirical analysis of Latin-American household surveys, we demonstrate that per capita income in the country of residence has the predicted effect on child labor supply, even after controlling for other household characteristics.     

Does the Welfare State Destroy the Family? Evidence from OECD Member Countries

We study the effect of the size of the welfare state on demographic trends in OECD member countries. Exploiting exogenous variation in public social spending, due to varying degrees of political fractionalization (i.e., the number of relevant parties involved in the legislative process), we show that an expansion in the welfare state increases fertility, marriage, and divorce rates with a quantitatively stronger effect on the marriage rate. We conclude that the welfare state supports family formation in the aggregate. Further, we find that the welfare state decouples marriage and fertility, and therefore alters the organization of the average family.     

On Clustering in the Location of R&D: Statics and Dynamics

Empirical analyses of research and development find strong evidence that these activities tend to cluster geographically. Clusters are thought to emerge from the presence of localized positive externalities. This paper presents a model of this clustering behaviour. We find that phase changes in clustering exist both as the strength of local externalities changes and as the degree of heterogeneity among firms changes. The dynamics of the system are examined as it responds to shocks to the size of the market for R&D output, and the length scale of the spatially dependent externalities. Dynamic responses take place in two distinct stages: a rapid response to the change in market systems which takes place throughout the space, with litlle regard to externality effects; followed by a slow re-agglomeration process as producers change their spatial decisions to lower the costs of the new production level.