Submitted on: 23 August 2006.
Revised on: 17 November 2006.
Accepted on: 12 January 2007.
___________________JOURNAL OF LABOR ECONOMICS---UNIV CHICAGO PRESS
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Submitted on: 25 July 2003.
Revised on: 03 September 2003.
Accepted on: 05 October 2003.
___________________JOURNAL OF LABOR ECONOMICS---UNIV CHICAGO PRESS
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Submitted on: 04 September 2000.
Revised on: 04 October 2000.
Accepted on: 23 November 2000.
___________________JOURNAL OF LABOR ECONOMICS---UNIV CHICAGO PRESS
Submitted on: 10 December 2011.
Revised on: 21 February 2012.
Accepted on: 17 April 2012.
___________________JOURNAL OF LABOR ECONOMICS---UNIV CHICAGO PRESS
Submitted on: 01 November 2022.
Revised on: 22 January 2023.
Accepted on: 08 March 2023.
___________________JOURNAL OF LABOR ECONOMICS---UNIV CHICAGO PRESS