Dora Costa & Matthew Kahn's "Heroes and Cowards"

Dora L. Costa is the author of The Evolution of Retirement: An American Economic History, 1880-1990. She teaches at the University of California, Los Angeles. Matthew E. Kahn is the author of Green Cities: Urban Growth and the Environment. He also teaches at UCLA. Costa and Kahn are research associates at the National Bureau of Economic Research.They applied the “Page 99 Test” to their new book,