https://doi.org/10.1371/journal.pone.0248361

Many countries have been implementing various control measures with different strictness levels to prevent the coronavirus disease 2019 (COVID-19) from spreading. With the great reduction in human mobility and daily activities, considerable impacts have been imposed on the global air transportation industry. This study applies a hybrid SARIMA-based intervention model to measure the differences in the impacts of different control measures implemented in China, the U.S. and Singapore on air passenger and air freight traffic. To explore the effect of time span for the measures to be in force, two scenarios are invented, namely a long-term intervention and a short-term intervention, and predictions are made till the end of 2020 for all three countries under both scenarios. As a result, predictive patterns of the selected metrics for the three countries are rather different. China is predicted to have the mildest economic impact on the air transportation industry in this year in terms of air passenger revenue and air cargo traffic, provided that the control measures were prompt and effective. The U.S. would suffer from a far-reaching impact on the industry if the same control measures are maintained. More uncertainties are found for Singapore, as it is strongly associated with international travel demands. Suggestions are made for the three countries and the rest of the world on how to seek a balance between the strictness of control measures and the potential long-term industrial losses.

In February 2014, Singapore embarked on a 2-year trial of a Bus Service Reliability Framework (BSRF) to improve en-route bus regularity and reduce instances of bus bunching and prolonged waiting times. Based on London's Quality Incentive Contract, the Singapore model also imposes penalties or provides incentives to operators for increases/reductions of Excess Wait Time (EWT) beyond a certain route-specific baseline. Drawing on insights derived from research on performance-based contracts, this paper describes some key considerations surrounding this particular innovation in Singapore's overall bus regulatory framework. We also discuss an important advancement in our understanding of how bus users value reliability improvements through estimates obtained from stated preference data. At the same time, early indications from the trial have been encouraging.