Received: 31 January 2017
Accepted: 23 January 2018
First Online: 20 February 2018
: AT is an assistant professor of statistics department at Bahir Dar University. He is a doctoral student at University of South Africa (UNISA) with close supervision of the two co-authors; recently he had four publications. PN is senior associate professor of University of South Africa with more than 10 publications. TZ is a full professor of University of Kwazulu Natal in South Africa with more than 70 publications in reputable journals. All the three authors together had two publications using the same data with the current one and on the same study area. This will be the third article for our PhD paper. The previous two articles are;OrderedList removed
: The investigators had got the ethical approval certificate from two universities namely, Bahir Dar University, Ethiopia, with Ref ≠ RCS/1412/2006 and University of South Africa (UNISA), South Africa, with Ref ≠: 2015-SSR-ERC_006. The ethical approval certificate can be attached up on request.
: Not applicable
: As no individual or institution funded this research, there was no conflict of financial and non-financial interest between authors or between authors and institutions.
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