Figure 1.

An entire study population for simulation studies. The 113 regions comprising wards, cities and villages in the area of Tokyo Metropolis and Kanagawa prefecture in Japan. The region number used in the text is shown. Especially, The region numbers of four hot-spot clusters A-D are A = {14, 15, 20}, B = {14, 15, 20, 26}, C = {14, 15, 26, 27}, and D = {73, 74, 75, 76, 78}, respectively.