Prior to his current position, he was a Project Researcher at the Graduate School of Economics, The University of Tokyo (2009-2013); and Research Associate (2004-2007) and Assistant Professor (2007-2009) at the Graduate School for Law and Politics, The University of Tokyo. He also served concurrently as Research Fellow (2009-2011) and Senior Research Fellow (2012-present) at The Canon Institute for Global Studies; and Senior Researcher at the Institute of Statistical Research (2013).