Peer effects in science : evidence from the dismissal of scientists in Nazi Germany

This paper analyzes peer e¤ects among university scientists. Specifically, it investigates whether peer quality and the number of peers a¤ect the productivity of researchers in physics, chemistry, and mathematics. The usual endogeneity problems related to estimating peer e¤ects are addressed by using the dismissal of scientists by the Nazi government as a source of exogenous variation in the peer group of scientists staying in Germany. Using a newly constructed panel dataset covering the universe of physicists, chemists, and mathematicians at all German universities from 1925 until 1938 I investigate localized peer e¤ects. There is no evidence for peer e¤ects at the local level. This surprising finding is robust for a large number of specification and robustness checks. In a second part of the analysis, I investigate peer e¤ect among co-authors and find that co-author quality is very important for scientific productivity