“…Two remarkable aspects can be highlighted: theory and application. Theoretically, several improved versions have been proposed, including the hybrid one (Xia, Chen, Zhang, & Wang, 2008), discrete one (Xie & Liu, 2009), intelligent algorithm-based ones (Bahrami, Hooshmand, & Parastegari, 2014;Hsu, 2010), least-squares-based one (Xu, Tan, Tu, & Qi, 2011), smart adaptive one (Truong & Ahn, 2012) as well as the fractional order-based one (Xiao, Guo, & Mao, 2014). On the other hand, the applications of GM(1, 1) are also enormous, such as accurate reliability prediction (Li, Masuda, Yamaguchi, & Nagai, 2010), fashion color forecasting (Yu, Hui, & Choi, 2012), hyperspectral feature extraction (Yin, Gao, & Jia, 2013), and end effects mitigation in our previous works .…”