The paper, by Raj Chetty and John N. Friedman of Harvard and Jonah E. Rockoff of Columbia, all economists, examines a larger number of students over a longer period of time with more in-depth data than many earlier studies, allowing for a deeper look at how much the quality of individual teachers matters over the long term.
“That test scores help you get more education, and that more education has an earnings effect — that makes sense to a lot of people,” said Robert H. Meyer, director of the Value-Added Research Center at the University of Wisconsin-Madison, which studies teacher measurement but was not involved in this study. “This study skips the stages, and shows differences in teachers mean differences in earnings.”