4.1 Model for hypothesis of “convergence” One model must be built to analyze the influence of population mobility on regional convergence. The study used a basic production function: JED Q AK HL . In the function, Q is general output, K is asset, L is labor, H is human capital, and A is a technical progress variable. According to the production function above and based on the data of three regions (the East, the Midst, and the West) mentioned in Li (2003) by means of regression analysis, the study built an additive separable model as follows: GDPi C PE ii ln( 78 ) , (1) where 'GDPi is the real increase rate of each province during 1978 to 2003 and ln( 78 ) GDP i is real per capita GDP of each province in 1978. X i is a serial of selectable explanatory variables, such as 'Labori , i 'Invest , ln( 78 ) Migrapop i , 'Migrapopi , Eastareaor WestareaFurthermore, in the period of 1978-2003, 'Migrapopi is average increase rate of net in-migration of each province per year, i 'Invest is average increase rate of total assets of each province, and 'Labori is average increase rate of labor (replaced by employed person here) of each province. ln( 78 ) Migrapop i is the logarithm of net in-migration and represents original value of population mobility of each province in 1978.