This paper attempts to examine community bus services in the Tama region of Tokyo in terms of the operational characteristics and the role of bus services that municipalities aimed for. In the process of adoption by municipalities, there was a certain degree of regional cohesiveness that surrounding municipalities of the precedents were likely to initiate their operations. In addition to analysis of fare systems, the percentages of bus routes independently operated by community bus operators were calculated based on GIS analysis to understand the role of community buses in the region. As a result, in the early 1990s, community bus services were provided in a manner similar to that of other bus services. On the other hand, municipalities began operating community buses in the late 1990s tended to fill the gap left by the declining services of private bus operators. In the 2000s, such examples led to their spread to neighboring municipalities and accelerated the adoption in the study region.

Recent advancements in information and communication technology have led to remarkable progress in the availability of urban spatial data. Among them, GIS data on population based on the national census is particularly well-developed. Urban planning practitioners, in particular, need to select the appropriate spatial unit（e.g., 250 meters, 500 meters, or 1 km）and criteria when examining changes in population density in a municipality. To this end, we develop a method for determining the appropriate grid square size for making histograms of population density based on computing the Akaike Information Criterion（AIC). Results of an empirical case study in Chiba prefecture show that histograms based on 1 km grid square is the best model of population density distribution in a municipality.