Science, technology, engineering, and mathematics ðSTEMÞ workers are fundamental inputs for innovation, the main driver of produc- tivity growth. We identify the long-run effect of STEM employ- ment growth on outcomes for native workers across 219 US cities from 1990 to 2010. We use the 1980 distribution of foreign-born STEM workers and variation in the H-1B visa program to identify supply-driven STEM increases across cities. Increases in STEM work- ers are associated with significant wage gains for college-educated natives. Gains for non-college-educated natives are smaller but still significant. Our results imply that foreign STEM increased total factor productivity growth in US cities.

It doesn't address his concerns but here's a relevant study. http://giovanniperi.ucdavis.edu/uploads/5/6/8/2/56826033/stem-workers.pdf