An analysis on urban shrinkage trends of all Japanese cities by detecting relative densely inhabited districts – Changes in urban form of Japanese cities in an era of shrinking population, part 2

Abstract

Abstract To analyze the method of urban shrinkage in Japan, a densely inhabited district (DID) has been applied in some previous studies as an index of urban areas or city centers. The problem with this method is that shrinkage in cities where no DID exists cannot be analyzed. Therefore, a relative threshold for urban areas or city centers is required. In this study, we propose a method for detecting a relative densely inhabited district (RDID) improved by information loss minimization. Furthermore, we identified the urban shrinkage or structural changes in Japanese cities using RDIDs and analyzed the changing trends from the years 1995–2015.

Keywords

• entropy
• information loss minimization
• relative densely inhabited district
• stages of urban development
• standard grid cell
• urban structure