Acknowledgments
For helpful comments, Joan Hannon and Steve Ziliak thank Susan Carter, Price Fishback, Brian Gratton, Monty Hindman, Peter Lindert, Robert Margo, John Schwarz, Matthew Sobek, and Richard Sutch. For research assistance, the work of Erin Mooney (Government Publications, Emory University), Susan Pozzanghera (Bowling Green State University), and the staff of the University of Iowa Government Publications Division is gratefully acknowledged. This work was made possible in part by grants from the Faculty Development Fund (Saint Mary's College of California) and the Office of Sponsored Programs (Bowling Green State University).
Price Fishback and Melissa Thomasson thank the Economics Department and the College of Business and Public Administration at the University of Arizona for financial support. Kari Beardsley, Amanda Ebel, Emie Portwood, and Kwok-Chung Wong provided help in collecting and computerizing the information. We received invaluable help from representatives at various government agencies: Ann Bixby at the Social Security Administration, Mike Finucan at the Office of Personnel Management, Marla Huddleston at the Railroad Retirement Board, Dan Peed at the Department of Labor, and Dora Teimouri at the U.S. Rehabilitation Service. A number of colleagues, including Susan Carter, Lee A. Craig, Brian Gratton, Joan Underhill Hannon, Monty Hindman, Shawn Kantor, Carolyn Moehling, John Schwartz, Matt Sobek, Richard Sutch, John Wallis, and Stephen Thomas Ziliak provided valuable help and advice on our essay and the organization and choice of tables.
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