The Department of Homeland Security estimates that 11.4 million undocumented persons reside in the United States. Congress and President Obama are considering a number of proposals to regularize the status of the undocumented population and provide a “path to citizenship.” Any future change...

The continuing inflow of hundreds of thousands of refugees into many European countries has ignited much political controversy and raised questions that require a fuller understanding of the determinants and consequences of refugee supply shocks. This paper revisits four historical refugee...

The continuing inflow of hundreds of thousands of refugees into many European countries has ignited much political controversy and raised questions that require a fuller understanding of the determinants and consequences of refugee supply shocks. This paper revisits four historical refugee...

Beginning in 1951, the Conference Board constructed a monthly job vacancy index by counting the number of help-wanted ads published in local newspapers in 51 metropolitan areas. We use the Help-Wanted Index (HWI) to document how immigration changes the number of job vacancies in the affected...

Knowledge producers conducting research on a particular set of questions may respond to supply and demand shocks by shifting resources to a different set of questions. Cognitive mobility measures the transition from one location to another in idea space. We examine the cognitive mobility flows...

It has been difficult to open up the black box of knowledge production. We use unique international data on the publications, citations, and affiliations of mathematicians to examine the impact of a large post-1992 influx of Soviet mathematicians on the productivity of their American...

The wage impact of immigration depends crucially on the elasticity of substitution between similarly skilled immigrants and natives and the elasticity of substitution between high school dropouts and graduates. This paper revisits the estimation of these elasticities. The U.S. data indicate that...