Evaluation of the sustainable development level of countries along the Belt and Road and its impact factors: Empirical analysis based on the Super-efficiency slacks-based measure and Tobit measure models

Sustainable development is an important component of the Belt and Road Initiative (BRI) and is of great significance for evaluating the levels of sustainable development of countries along this route (henceforth, BRI countries). Therefore, this study aims to identify the factors that influence the levels of sustainable development of BRI countries in a reasonable and objective manner. Eventually, this study employs the super-efficiency slacks-based measure (Super-SBM) model, which considers unexpected outputs to measure the level of sustainable development of BRI countries. The dynamic change and composition of the sustainable development level of these countries are calculated using the global Malmquist–Luenberger index. Furthermore, the Tobit model is used to identify the factors influencing the level of sustainable development of BRI countries in general and in various categories. The empirical results suggest the following points. (a) The overall level of sustainable development of BRI countries is low, whereas those of high-income and middle- and high-income countries are relatively high. (b) The overall sustainable development levels of BRI countries declined to a certain extent in 2008 owing to the effect of the financial crisis,. However, the sustainable development level of other countries, barring low-income countries, has gradually increased since 2011. (c) Since 2008, technological progress has replaced technical efficiency as the main driving force behind the improvement of the sustainable development level of BRI countries. (d) A U-shaped relationship is observed between the economic and sustainable development levels of these countries. (e) The level of science and technology and the proportion of renewable energy consumption can promote the sustainable development of these countries. Moreover, a negative correlation exists between the level of opening to the outside world and that of sustainable development of countries that mainly export resource-based products and are dominated by labor-intensive export industries. Barring low-income countries, the energy structure plays an effective role in improving the level of sustainable development. Finally, the study presents suggestions for China in the process of coping with the sustainable development of relevant countries during its promotion of the BRI