In recent years, bike-sharing has experienced rapid development; however, controversies about the externalities of bike-sharing programs have arisen as well. While bike-sharing programs have impacts on traffic, the environment, and public health, the social impacts, the management, and sustainable development of bike-sharing has also been of interest. The debate regards whether there are externalities, as well as whether and how such externalities can be determined. Based on the rapidly diffused bike-sharing in China, this paper quantitatively explores bike-sharing externalities. Specifically, this paper estimates the impacts of bike-sharing on the economy, energy use, the environment, and public health. The empirical results show that bike-sharing programs have significant positive externalities. The bike-sharing systems can provide urban residents with a convenient and time-saving travel mode. We find that the bike-sharing dramatically decreases traffic, reduces energy consumption, decreasing harmful gas emissions, improves public health generally, and promotes economic growth. This study contributes to a better comprehension of the externalities of bike-sharing and provides empirical evidence of the impacts of bike-sharing. Findings suggest that bike-sharing can play a critical role in the process of urban transportation development and provide information useful for urban transportation policies.

The air pollution has become a serious challenge in China. Emissions from motor vehicles have been found as one main source of air pollution. Although the Chinese government has taken numerous policies to mitigate the harmful emissions from road transport sector, it is still uncertain for both policy makers and researchers to know to what extent the policies are effective in the short and long terms. Inspired by the concept and empirical results from current literature on energy rebound effect (ERE), we first propose a new concept of pollution rebound effect (PRE). Then, we estimate direct air PRE as a measure for the effectiveness of the policies of reducing air pollution from transport sector based on time-series data from the period 1986-2014. We find that the short-term direct air PRE is -1.4105, and the corresponding long-run PRE is -1.246. The negative results indicate that the direct air PRE does not exist in road passenger transport sector in China, either in the short term or in the long term during the period 1986-2014. This implies that the Chinese transport policies are effective in terms of harmful emissions reduction in the transport sector. This research, to the best of our knowledge, is the first attempt to quantify the effectiveness of the transport policies in the transitional China.