Submitted on: 21 May 1999.
Revised on: 26 July 1999.
Accepted on: 29 August 1999.
___________________Journal of Human Capital---UNIV CHICAGO PRESS
Submitted on: 10 June 2015.
Revised on: 10 July 2015.
Accepted on: 01 August 2015.
___________________Journal of Human Capital---UNIV CHICAGO PRESS
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Submitted on: 08 December 2024.
Revised on: 20 February 2025.
Accepted on: 04 March 2025.
___________________Journal of Human Capital---UNIV CHICAGO PRESS
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Submitted on: 08 April 2009.
Revised on: 23 June 2009.
Accepted on: 10 July 2009.
___________________Journal of Human Capital---UNIV CHICAGO PRESS
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Submitted on: 11 September 2001.
Revised on: 18 December 2001.
Accepted on: 14 January 2002.
___________________Journal of Human Capital---UNIV CHICAGO PRESS
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