1. Department of Information Science and Engineering, Ritsumeikan University, Kusatsu, Japan
2. The Institute of Statistical Mathematics, Tachikawa, Japan
3. SOKENDAI (The Graduate University for Advanced Studies), Tokyo, Japan
4. Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, Japan
5. Faculty of Languages and Cultures, Kyushu University, Fukuoka, Japan
6. Graduate School of Information Sciences, Tohoku University, Sendai, Japan
7. RIKEN Center for Advanced Intelligence Project, Chuo-ku, Japan
8. Advanced Sciences, Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo, Japan
9. Department of Mechanical Engineering and Intelligent Systems, The University of Electro-Communications, Chofu, Japan
10. Department of Information and Communication Engineering, Okayama Prefectural University, Okayama, Japan
11. National Institute of Informatics, Tokyo, Japan