Submitted on: 15 November 2009.
Revised on: 27 December 2009.
Accepted on: 10 January 2010.
MIT SLOAN MANAGEMENT REVIEW
http://reply.papertrans.cn/3/221/22098/22098-32.png
http://reply.papertrans.cn/3/221/22098/22098-33.png
Submitted on: 09 October 2021.
Revised on: 19 October 2021.
Accepted on: 11 November 2021.
MIT SLOAN MANAGEMENT REVIEW
http://reply.papertrans.cn/3/221/22098/22098-35.png
http://reply.papertrans.cn/3/221/22098/22098-36.png