Submitted on: 07 December 2011.
Revised on: 02 January 2012.
Accepted on: 13 January 2012.
___________________Annals of Actuarial Science---CAMBRIDGE UNIV PRESS
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Submitted on: 20 March 2022.
Revised on: 15 April 2022.
Accepted on: 21 May 2022.
___________________Annals of Actuarial Science---CAMBRIDGE UNIV PRESS
Submitted on: 19 February 2002.
Revised on: 09 June 2002.
Accepted on: 26 June 2002.
___________________Annals of Actuarial Science---CAMBRIDGE UNIV PRESS
Submitted on: 17 August 2007.
Revised on: 21 October 2007.
Accepted on: 16 December 2007.
___________________Annals of Actuarial Science---CAMBRIDGE UNIV PRESS