8. Evaluating China’s Investment Network and Mega-regions

City clusters, mega-regions and metropolitan regions are all words been used to describe designated areas for regional and national policies and engine for economic development. In recent years, Chinese central government has proposed a structure of “5 + 9 + 6” mega-regions, including several new mega-regions. Those regions has been seen as an important element in directing the next stage of regional developments. Beyond those well-known regions like Pearl River Delta (PRD) and Yangtze River Delta (YRD), many have been seen as unsettled. In order to support the establishment of inter-regional institution and the coordination of regional infrastructure development, a better evaluation about national cities’ connection and the development of mega-region is needed. In this article, we use the records of company investment data aggregated by prefectural level cities to reconstruct an interactive network. By using a historical series of network data we are able to study the evolution of national investment network. Indicators like network density and the pattern of degree distribution are used to describe the development of investment network. Through machine learning methods, the nation’s cities’ hierarchical structure is unveiled. In order to take a deeper look into mega-regions’ development mechanism and measure their inner-region economic connection, algorithm for detecting cohesive subgroup is used. Based on the result and cities’ hierarchical structure, further development strategies for typical mega-regions are provided.