Evaluating environmental outcome and process-adaptivity of regional collaboration: An empirical study from China

Since the 2000s, China has enforced regional collaboration as a way of resolving cross-diffused air pollution and jurisdictional limitations. It is, however, a hotly debated issue as to whether authority-driven regional collaboration can be sustained and effective, and no consensus has been achieved by the theoretical discussion. Despite extensive empirical research on the topic, most studies judged the sustainability of collaborations by analyzing the environmental outcomes within a short period after their initiation. To provide more comprehensive empirical evidence to the open question, this paper introduces the criterion of adaptivity to determine whether collaboration is sustainable. Taking the changing collaboration in Beijing-Tianjin-Hebei and its surroundings as a quasi-natural experiment, Difference-in-Difference model and Triple Difference Model are used to verify the adaptivity from two aspects. Results show that authority-driven collaboration adjustment yields better environmental outcomes. Additionally, the better environmental outcome is observed in original collaborators, implying that local governments can learn by doing and form interdependence through repeated collaborative actions. The adaptive collaboration, however, has two limitations. First, the collaboration mechanism is formed primarily based on performance evaluation and target assessment instruments, without showing adaptivity in reducing soft control indicators of air pollution. Second, the different regulation pressure between non-collaborating and collaboration cities results in undesirable spillover effects within a range of 40-100 km. This study not only contributes to empirical and theoretical studies on regional collaboration but also provides support to the improvement of the collaboration system in practice.