The Institute of Statistical Mathematics, 4-6-7, Minami Azabu, Minato-ku, Tokyo, 106-8569 Japan
Earthquake Hazards Division, Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji, Kyoto, 611-0011 Japan
Center for Computational Science and Engineering, c/o Department of Physics, University of California at Davis, One Shields Avenue, Davis, CA 95616 United States
Department of Geology, University of California at Davis, One Shields Avenue, Davis, CA 95616 United States