Text and Data Mining valid from 2019-04-11
Received: 6 December 2018
Revised: 11 February 2019
Accepted: 18 March 2019
First Online: 11 April 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: For the convenience of other researchers, the involved codes of the proposed two-stage polynomial response surface are included in the supplementary online material.