Akihiro Otsuka Yokohama City University   22-2 Seto, Kanazawa Yokohama, Kanagawa 236-0027 Japan   otsuka@yokohama-cu.ac.jp   https://researchmap.jp/7000015294/?lang=english           JEL Areas: R : Urban, Rural, and Regional Economics R1 : General Regional Economics (includes Regional Data)