http://reply.papertrans.cn/3/287/28607/28607-11.png
http://reply.papertrans.cn/3/287/28607/28607-12.png
http://reply.papertrans.cn/3/287/28607/28607-13.png
Submitted on: 21 May 2019.
Revised on: 06 June 2019.
Accepted on: 18 June 2019.
Stata Journal
Submitted on: 02 September 2016.
Revised on: 27 September 2016.
Accepted on: 16 October 2016.
Stata Journal---SAGE PUBLICATIONS INC
Submitted on: 27 May 2019.
Revised on: 07 July 2019.
Accepted on: 04 August 2019.
Stata Journal
Submitted on: 04 May 2022.
Revised on: 29 May 2022.
Accepted on: 07 June 2022.
Stata Journal---SAGE PUBLICATIONS INC
http://reply.papertrans.cn/3/287/28607/28607-18.png
http://reply.papertrans.cn/3/287/28607/28607-19.png
Submitted on: 03 June 2023.
Revised on: 15 June 2023.
Accepted on: 02 July 2023.
Stata Journal---SAGE PUBLICATIONS INC