Submitted on: 09 January 2014.
Revised on: 12 March 2014.
Accepted on: 08 May 2014.
___________________JOURNAL OF APPLIED ECONOMETRICS
Submitted on: 22 September 2007.
Revised on: 14 December 2007.
Accepted on: 25 January 2008.
___________________JOURNAL OF APPLIED ECONOMETRICS
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