First Author:   Jong Chil Son Division of Economics, Hankuk University of Foreign Studies jcson@hufs.ac.kr   Seoul, 02450, Korea   82-2-2173-3043(Phone) 82-2-2173-3043(Fax) Second Author: Youngjoo Choi Monetary Policy Department, the Bank of Korea yjchoi@bok.or.kr   39 Namdaemun-ro, Jung-gu Seoul, 14531, Korea   82-2-759-4488(Phone)