Many individuals have strong preferences towards COVID-19 vaccines and would like to choose the vaccine they get. This practice, known as “vaccine shopping,” presents unique challenges to timely vaccine rollout: on the one hand, people may not get vaccinated if they are unable to receive...

Online shopping surged in the initial months of the COVID-19 pandemic, accelerating the pre-pandemic shift toward increased online consumer activity. This trend fed into concerns over the success of top retailers at the expense of smaller ones. Further, it raised questions of whether consumers...