The market for payment cards is inherently two sided. Consumers benefit from increased merchant acceptance of payment cards and vice versa. To quantify the interdependence of consumer and merchants or network externalities, we construct and estimate a structural two-sided model of a payment...

Why do BigTech platforms introduce payment services? Digital platforms often run business models where activities on the platform generate data that can be monetized off the platform. There is a trade-off between the value of such data and the privacy concerns of users, since platforms need to...

An anonymous credential mechanism is a set of protocols that allows users to obtain credentials from an organization and demonstrate ownership of these credentials without compromising users' privacy. In this work, we construct the first secret-free and quantum-safe credential mechanism. The...

Digital payments and decentralized systems enable the creation of new financial products and services for users. One core challenge in digital payments is the need to protect users from fraud and abuse while retaining privacy in individual transactions. We propose a pseudonymous credential...