From: Evaluating Public Programs with Close Substitutes: The Case of Head
Start*
Q J Econ. 2016;131(4):1795-1848. doi:10.1093/qje/qjw027
Q J Econ | © The Author(s) 2016. Published by Oxford University Press, on
behalf of President and Fellows of Harvard College. All rights reserved. For
Permissions, please email: [email protected]