Robust response surface design for quantitative and qualitative factors

Abstract

Wu and Ding (1991) have given a systematic method for constructing the response surface designs for qualitative and quantitative factors when all the quantitative factors are controllable. In most of the experiments all the quantitative factors are not controllable some of them are uncontrollable or noise factors. In this paper we have given a method for constructing designs involving qualitative and quantitative factors using the technique given by Wu and Ding (1991) when the quantitative factors are divided into controllable and uncontrollable factors. We have also applied dual response surface optimization technique given by Lin and Tu (1995) to find the optimal setting for a set of design variables involving qualitative and quantitative factors.