Abstract
Using detailed scheduling data on a total of 13.8 million domestic flights in China from 2011 to 2016, this paper quantifies the substitution effects of HSR on air travel, as measured by the monthly flight frequency and the average number of seats per flight for each air route, employing difference-in-differences (DID) and propensity score matching (PSM) approaches. We find that HSR has a significant negative impact on monthly flight frequency: on average, the introduction of HSR has led to a 10.1% drop in the monthly number of flights per route. However, this average impact conceals significant heterogeneity by distance. The comprehensive coverage of flights from 2011 to 2016 allows us to divide the full sample into sufficiently large sub-samples by every 200 km distance band. Results indicate significantly larger substitution effect for routes of shorter distance and the cutoff distance is 900 km, beyond which no effect of HSR connection on air travel is observed. We further apply the PSM approach in an event study analysis to alleviate selection bias and obtain similar results. Moreover, the HSR-induced decrease in flight frequency was most substantial in routes between hub cities. Based on our estimates, the spared CO2 emissions due to HSR-induced air travel decrease amount to 2 million tonnes annually, and energy saving is about 19.33 PJ annually. Our research not only provides important implications for transport policy in terms of multi-mode intercity transport planning, but also provides more accurate estimates about the carbon emission reduction through the substitution between HSR and air travel, thereby better informing evidence-based decision-making in transportation and environmental policy.
The Role of High-speed Rail and Air Travel in the Spread of COVID-19 in China
