Submitted on: 23 April 2000.
Revised on: 28 May 2000.
Accepted on: 18 June 2000.
Korean Journal of Applied Statistics
Submitted on: 13 June 2004.
Revised on: 27 July 2004.
Accepted on: 06 August 2004.
Korean Journal of Applied Statistics
Submitted on: 31 July 2010.
Revised on: 11 September 2010.
Accepted on: 24 September 2010.
Korean Journal of Applied Statistics
Submitted on: 02 November 2010.
Revised on: 20 November 2010.
Accepted on: 02 December 2010.
Korean Journal of Applied Statistics
Submitted on: 23 August 1998.
Revised on: 01 September 1998.
Accepted on: 08 September 1998.
Korean Journal of Applied Statistics
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