The late Kohei Ohtsu was a Professor Emeritus of Tokyo University of Marine Science and Technology. He has served as Vice President of Tokyo University of Mercantile Marine, Captain of the Training Ship Shioji Maru of the University, and President of Ohtsu Maritime Institute, Co. Ltd. His main research interests include statistical analysis of ship motion and optimal steering, ship maneuverability and practical application of ship-to-shore communication and ship operation data monitoring. He received awards from The Society of Naval Architects of Japan, Japan Institute of Navigation, The Society of Instrument and Control Engineers and the Japan Society of Naval Architects and Ocean Engineers, etc. He passed away in 2016 at the age of 72. Genshiro Kitagawa is a professor emeritus of The Institute of Statistical Mathematics, and of Graduate University for Advanced Study, former President of the Research Organization of Information and Systems, and the former Director-General of the Institute of Statistical Mathematics. His primary research interests are time series modeling, nonlinear filtering and statistical modeling. He is the author of several English books on time series analysis and information criteria. He was awarded the Japan Statistical Society Prize and Ishikawa Prize, etc. and is a Fellow of the American Statistical Association.