Interactive Correlation between Economy and Integrated Transportation Development of Metropolitan Areas in China: Quantitative Study

This study aims to propose a comprehensive evaluation index for the economy and integrated transportation system of metropolitan areas to analyze the interactive correlations between them and, thus, determine their developmental trends and characteristics, as well as the developed and developing metropolitan areas in China from 1998 to 2017. Moreover, a combination of a time-domain analysis and frequency-domain analysis was adopted to explore the interactive evolution correlation and spatial differences between both methods for 1998–2017. The sustainable developments of both metropolitan areas and China’s integrated transportation exhibited a steady upward trend, and the gap between the developed and the developing metropolitan areas showed an expanding trend. While long-term equilibrium interactions were noted between both, some variances were present in different regions at different times. While China and its developed metropolitan areas were of a pulling type, the developing metropolitan areas were of a promoting type. Besides, the impact of integrated transportation development on the economy of the metropolitan areas was more significant, and the degree of impact exhibited a high trend in the developed metropolitan areas but a common trend in the developing metropolitan areas.