Submitted on: 31 May 2016.
Revised on: 08 July 2016.
Accepted on: 21 July 2016.
Stata Journal
Submitted on: 13 January 2006.
Revised on: 08 February 2006.
Accepted on: 13 February 2006.
Stata Journal
Submitted on: 02 December 2011.
Revised on: 13 January 2012.
Accepted on: 06 February 2012.
Stata Journal---SAGE PUBLICATIONS INC
Submitted on: 24 July 2000.
Revised on: 22 August 2000.
Accepted on: 16 September 2000.
Stata Journal
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Submitted on: 12 November 2002.
Revised on: 28 November 2002.
Accepted on: 19 December 2002.
Stata Journal
Submitted on: 15 April 2021.
Revised on: 21 May 2021.
Accepted on: 16 June 2021.
Stata Journal---SAGE PUBLICATIONS INC
Submitted on: 18 September 2000.
Revised on: 14 October 2000.
Accepted on: 07 November 2000.
Stata Journal
Submitted on: 06 October 2015.
Revised on: 18 November 2015.
Accepted on: 07 December 2015.
Stata Journal