Yuan Ren

We utilize the introduction of mobile payment technology by the largest bank in Singapore in 2017 to study how mobile payment technology reshapes economic activities and stimulates business creation. After the introduction, business-to-consumer industries witnessed 18.3% more business creation relative to business-to-business industries, with the effect driven by small firms and more pronounced among industries with higher cash handling costs. Underlying this pattern is consumers’ strong adoption of mobile payment and a reduction in ATM cash withdrawals during the post-shock period. The reduced transaction cost also increases consumers’ spending capacity, which justifies the business growth. Interestingly, part of the increased consumer demand is credit card spending. The pattern of changes is consistent with the bank’s adjustment to the technological change: it reduces ATMs and allows more credit card openings and higher credit limits. This paper was accepted by Camelia Kuhnen, finance. Funding: Y. Ren received financial support from the National Natural Science Foundation of China [Grant 72303210], the Zhejiang Provincial Natural Science Foundation of China [Grant LQ24G010001], and the major project of the National Social Science Fund of China [Grant 24&ZD088]. S. Agarwal acknowledges the financial support from the National Natural Science Foundation of China [Grant 72495154]. Supplemental Material: The internet appendix and data files are available at https://doi.org/10.1287/mnsc.2023.03947 .

Introduction: Globally, hypertension stands as the foremost preventable risk factor for cardiovascular disease and premature death. However, scalable approach to lowering blood pressure (BP) at the population level remains lacking. We investigated whether shared bikes, a sustainable method of transportation gaining increasing popularity across the world, can serve as a supplemental instrument to combat the increasing prevalence of hypertension. Methods: Based on 8 107 363 physical examination visits to one of the largest medical examination centres in China during the period of June 2016 to August 2017, we perfermed a staggered difference-in-differences (DiD) analysis that exploited the roll-out of bike-sharing systems across different cities. The main outcome was the blood pressure among adult participants who were likely to adopt shared bikes (age <45), measured by (1) systolic blood pressure (SBP), (2) diastolic blood pressure (DBP) and (3) a binary indicator of hypertension status (SBP≥130 or DBP≥80 mm Hg). Results: Blood pressure showed a decreasing trend after a bike-sharing platform entered the local city. After 6 months post an entry event, SBP reduced by 0.67 mm Hg (β (SE), −0.672 (0.245); 95% CI, −1.154 to −0.191); the prevalence of hypertension reduced by 1.4 percentage points (β (SE), −0.014 (0.007); 95% CI, −0.027 to −0.000); the reduction in DBP was statistically insignificant (β (SE), −0.193 (0.193); 95% CI, −0.572 to 0.187). Participants less likely to adopt shared bikes (age ≥45) showed no significant response. The number of visits and the age of participants were also unaffected by the entry events. Reduction in blood pressure was more pronounced in male, younger and non-obese participants. Conclusion: The findings of this study suggest that bike-sharing systems in China may be associated with lowered blood pressure, and thus may serve as a supplemental instrument to combat the increasing prevalence of hypertension, especially among young adults.

Using a representative sample of credit card holders from a leading Chinese commercial bank, we investigate how consumers respond to an unexpected interest rate decrease that automatically reduces interest expenses for all mortgage borrowers in the country and thereby generates significant positive disposable-income shocks. Our difference-in-differences analysis shows that compared with homeowners without mortgage obligations, mortgage borrowers increased their monthly credit card spending by 8.7% after the 230-bps mortgage rate reduction announced in September 2008. We find a significant spending response both immediately after the announcement and during the post-reset period. The credit card delinquency rate also decreased after the mortgage rate reset. Subsequent to an interest-rate increase episode, mortgage borrowers symmetrically reduced their credit card spending. Hand-to-mouth mortgage borrowers experienced a more pronounced spending increase. The debt-service channel plays an important role in transmitting monetary policy—our estimate implies a marginal propensity to consume 0.40–0.54 through credit card spending.