Spatial concentration of economic activities is one of the most salient features of economic development. The almost parallel urge by policymakers to counteract such a trend through public polices is also striking. This is not only reserved to those countries, especially in Europe, which have a...

In the COVID-19 pandemic, governments have, among other measures, mandated the use of COVID certificates to prove vaccination, recovery or a recent negative test, and have required individuals to show certificates to access shops, restaurants, and education or workplaces. While arguments for and...