1. Tohoku University, Graduate School of Economics and Management, 27-1 Kawauchi Aoba-ku, Sendai 980-8576, Japan
2. The Dai-ichi Life Insurance Company, Limited, 1-13-1 Yurakucho Chiyoda-ku, Tokyo 100-8411, Japan
3. Mitsubishi UFJ Trust Investment, Technology Institute Co., Ltd. (MTEC), Sumitomo Fudosan Shin-Akasaka Bldg. 10F, 4-2-6 Akasaka Minato-ku, Tokyo 107-0052, Japan