Research on Classification Methods and Spatial Patterns of the Regional Types of China's Floating Population

With the rapid increase of the number and influence of floating population in China,it is urgent to understand the regional types of China's floating population and their spatial characteristics.After reviewing the current methods for identifying regional types of floating population,this paper puts forward a new composite-index method and its further modification method consisting of two indexes simultaneously: the net migration rate and gross migration rate.Further,those methods are empirically tested by using China's 2000 Census data at county level.The results show:(1) The composite-indexes method is much better than the traditional single-index method because it can measure the migration direction and scale of floating simultaneously and in particular it can identify the unique regional types of floating population with large-scale immigration and emigration.(2) The modified composite-indexes method,by using the share of a region's certain type of floating population to the total in China as weight,can effectively correct the over-or under-estimated error due to the rather large or small total population of a region.(3) The spatial patterns of different regional types of China's floating population are closely related to regional differentiation of their natural environment,population density and socio-economic development level.The three active regional types of floating population are mainly located in the eastern China with lower elevation,more than 800 mm precipitation,rather than in the region with higher population density and economic development level.