Ⅰ. What is "Tokyo flu"
or
This data set is applicable to Costomized City Network.
The historical raw data of Tokyo region was downloaded through Tokyo Metropolitan Infectious Disease Surveillance Center (Link: http://survey.tokyo-eiken.go.jp/epidinfo/weeklyhc.do).
For each ward or district, the raw data were averaged in terms of the total number of clinics within the ward/district. This normalization process is directly related to the population of each ward/district, since the population is roughly proportional to the number of clinics.