Integrating set pair analysis and social network analysis to explore the distribution pattern and return flow mechanism of floating population: A case study of Heilongjiang Province, China

Under the background of accelerating the development of new quality productivity in China, population mobility, as a key factor, has become increasingly prominent in its spatial reorganization mechanism and regional differential effect. Based on Baidu migration big data and statistical yearbook data, this paper constructs a set pair-social network analysis method, optimizes social network data, enhances network characteristics, and comprehensively describes the network pattern of inter-provincial population mobility. Taking Heilongjiang Province of China as an example, this paper deeply analyzes the spatio-temporal evolution characteristics of population mobility and the driving mechanism of return flow of new quality productivity. The results show that the national population mobility network shows significant small-world characteristics and "core-edge" structure, and the regions with higher levels of new quality productivity occupy the hub position in the network. Heilongjiang Province is on the edge of the population flow network, with continuous outflow of population and highly uneven spatial distribution. The regression analysis shows that the new quality productivity has a significant negative impact on the overall population net flow in Heilongjiang Province, reflecting the mismatch between the development model of new quality productivity with technology intensive and low employment elasticity and the structure of local labor force. However, in cities with low population density, the new quality productivity has a significant role in promoting population return. The results show that the new quality productivity does not naturally have a population attraction effect, and its population effect highly depends on the matching degree between regional industry carrying capacity and population structure. This paper provides a new theoretical perspective and empirical basis for understanding the population mobility mechanism in developing regions and formulating differentiated population return policies.