Research on Shrinking City Identification under Unsupervised Learning——Based on Nine cities belonging to Guangdong Province in Guangdong-Hong Kong-Macao Greater Bay Area

We took nine cities belonging to Guangdong Province in Guangdong-Hong Kong-Macao Greater Bay Area as an example. Through the collection of statistical data, Weibo user behavior data and DMSP/OLS data, the identification system of shrinking city composed of 45 indexes from the four dimensions of economy, population, spatial geography and administration, is preliminarily established.