1. Kogod School of Business, American University, 4400 Massachusetts Avenue NW, Washington, DC 20016 (email: )
2. School of Economics, Seoul National University, San 56-1, Silimdong, Kwanak-ku, Seoul 151-742, Korea (email: )
3. Bank for International Settlements, Centralbahnplatz 2, CH-4002 Basel, Switzerland (email: )