Submitted on: 20 September 2013.
Revised on: 29 September 2013.
Accepted on: 21 October 2013.
SOUTH AFRICAN STATISTICAL JOURNAL
Submitted on: 06 July 2006.
Revised on: 15 August 2006.
Accepted on: 30 August 2006.
SOUTH AFRICAN STATISTICAL JOURNAL
Submitted on: 07 September 2013.
Revised on: 22 September 2013.
Accepted on: 30 September 2013.
SOUTH AFRICAN STATISTICAL JOURNAL
Submitted on: 07 April 2017.
Revised on: 18 April 2017.
Accepted on: 27 April 2017.
SOUTH AFRICAN STATISTICAL JOURNAL
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Submitted on: 04 August 2013.
Revised on: 01 September 2013.
Accepted on: 20 September 2013.
SOUTH AFRICAN STATISTICAL JOURNAL
Submitted on: 09 May 2002.
Revised on: 24 May 2002.
Accepted on: 30 May 2002.
SOUTH AFRICAN STATISTICAL JOURNAL
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