Ruifeng Liu, ruifeng076@163.com, No.15 Longzi Lake College Park, Zhengzhou Eastern New District, Zhengzhou 450046. Dr. Ruifeng Liu is an associate professor of College of Economics and Management at Henan Agricultural University, China. He received his PhD degree from Xinjiang Agricultural University in 2010. His research focused on market research, consumer behavior, choice modeling, and applied econometrics.