How Much Does Immigration Boost Innovation? ∗
Jennifer Hunt †
McGill University and NBER
February 18, 2008
∗I am grateful to David Munroe for excellent research assistance, and for helpful comments to Francisco
Alvarez–Cuadrado, Leah Brooks, David Card, Lee Fleming, Rachel Friedberg, David Green, Francisco
Gonzales, Chad Jones, Daniel Parent, Giovanni Peri, Regina Riphahn, Eric Stuen and Dee Suttiphisal.
I thank Jim Hirabayashi of the USPTO and Nicole Fortin for data and Deven Parmar for obtaining and
formatting the USPTO data. I am also affiliated with the CReAM, CEPR, IZA and DIW-Berlin, and I
acknowledge the Social Science and Humanities Research Council of Canada for financial support.
†Department of Economics, McGill University, 855 Sherbrooke Street West, Montreal, QC, H3A 2T7,
Canada; tel. (514) 398-6866; fax (514) 398-4938.
I combine patent, decennial census and other data to measure the extent to
which skilled immigration increased innovation in the United States from 1950–
2000. I instrument the change in the share of skilled immigrants in a state with the
initial share of immigrant high school dropouts from Europe, China and India, and
consider changes of between ten and 50 years. I find that a one percentage point rise
in the share of immigrant college graduates in the population increases patenting by
8–15%; the equivalent range for immigrants with post–college education is 15–33%.
A one percentage point rise in the share of immigrant scientists and engineers in
the workforce increases patenting by at least 41%. The effects are similar in the
short and long run, and appear to be much larger than the effect of skilled natives,
especially in the short run. This may be related to my finding that natives are
crowded out by immigrants in the short run, but not in the long run. My analysis
shows the importance of convergence among states for the evolution of patents.
Although there is a large literature studying the impact of immigration on the host
country, this literature