First Author:   Pisey Khin The Economic Institute of Cambodia pisey.khin@gmail.com         Second Author: Ryuta Ray Kato International University of Japan kato@iuj.ac.jp   777 Kokusai-cho Minami-Uonuma, 949-7277, Japan   +81-(0)25-779-1510(Phone) +81-(0)25-779-1510(Fax)