Abstract
This study examines the spatial patterns of population change in the 23 Special Wards of Tokyo after the period of the bubble economy in the late 1980s. To this end, we analyze grid square data suitable for time-series analysis between 1985, when the bubble economy started, and 2005, the latest year for which data are available, using a geographic information system (GIS). After selecting major indicators representing three dimensions of the social area analysis--family status, socioeconomic status, and ethnic status--we map each indicator and make quantitative comparisons between six zones, classified by distance from the city center, and between four sectors classified by direction from the city center. The indicators used in this study are three variables representing family status (rate of young population, rate of elderly population, and rate of single-person families), three variables representing socioeconomic status (rate of blue collar workers, rate of managers and officials, and rate of professional and technical workers), and one variable representing ethnic status (rate of non-Japanese people). Before analyzing these data, we examine the spatial pattern of population change in the 23 Special Wards between 1985 and 2005. This analysis reveals that a population recovery has occurred since the latter half of the 1990s in central Tokyo, where a previous population decline had continued until 1995. On the basis of this trend of population change, we examine the spatial pattern of each indicator in the social atlas. Concerning age and household composition (representing family status), its spatial distribution has gradually shifted from a zonal pattern to a sectoral one owing to the migration of nuclear families to the area surrounding the city center. The spatial distribution of socioeconomic status represented by the occupational structure maintained a sectoral pattern characterized by the contrast between the eastern and western parts of Tokyo although this distinction has blurred. In particular, the number of managers and officials in the 23 Special Wards has decreased and its distribution shifted to a zonal pattern, which indicates the polarization of white-collar workers. The distribution of non-Japanese shows a zonal pattern in which the highest value appeared in the area surrounding the city center. However, spatial autocorrelation analysis of the distribution of four major ethnic groups by nationality reveals a clustered pattern, supporting the findings of previous studies in Western countries.
