Submitted on: 15 April 1999.
Revised on: 07 August 1999.
Accepted on: 27 September 1999.
___________________JOURNAL OF HUMAN RESOURCES---UNIV WISCONSIN PRESS
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Submitted on: 27 October 2005.
Revised on: 05 January 2006.
Accepted on: 22 February 2006.
___________________JOURNAL OF HUMAN RESOURCES---UNIV WISCONSIN PRESS
Submitted on: 05 February 2013.
Revised on: 21 May 2013.
Accepted on: 02 June 2013.
___________________JOURNAL OF HUMAN RESOURCES---UNIV WISCONSIN PRESS
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Submitted on: 18 March 2001.
Revised on: 08 June 2001.
Accepted on: 19 July 2001.
___________________JOURNAL OF HUMAN RESOURCES---UNIV WISCONSIN PRESS
Submitted on: 14 July 2021.
Revised on: 10 August 2021.
Accepted on: 10 September 2021.
___________________JOURNAL OF HUMAN RESOURCES---UNIV WISCONSIN PRESS
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