Abstract: There exists a mutually promoting collaborative relationship between digital service trade and digital infrastructure, however, the traditional measurement methods are difficult to accurately analyze this issue. Under the framework of social network analysis, this paper uses the random actor dominated model to explore this issue in detail. The findings show that there exists a synergistic development relationship between the digital infrastructure of an economy and the trade in digital services, which mutually affects each other. The well-developed digital infrastructure of both parties can reduce their costs of digital service trade, and thus have a significant positive impact on the import and export of digital service trade. The digital service trade will also affect the construction of digital infrastructure in economies: under the impact of the two mechanisms of internal incentives and external spillovers, to carry out digital service trade with economies with good digital construction will enhance their own digital infrastructure level. Through a heterogeneity analysis of different industries, it is found that digital infrastructure has the greatest impact on the intellectual property usage fees and the export ofother commercial services, and a greatest impact on the import of personal entertainment services, while the import and export trade of personal entertainment services has the greatest impact on digital infrastructure. Therefore, the government should play a leading role in promoting the coordinated and stable development of digital trade and digital construction by formulating reasonable plans, actively seeking international cooperation, and emphasizing the development of cultural industries.

Key words: digital infrastructure, digital service trade, stochastic actor oriented model, social network