“…So far, various SDR methodologies have been developed to estimate S Y|X in multivariate regression. Various SDR methodologies for multivariate regression have been proposed (Lee et al, 2019;Setodji and Cook, 2004;Yin and Bura, 2006;Yoo, 2008Yoo, , 2009Yoo and Cook, 2007;Yoo et al, 2010). In Setodji and Cook (2004) and Yoo et al (2010), an inverse regression approach, called K-means inverse regression (KIR) and K-means average variance estimation, is adopted, while the other methods combine the information from the coordinate regression of…”