Selected Working Papers

• Payment Firms, Cryptocurrencies, and CBDCs, with Tobias Berg (Goethe University Frankfurt), Felix Martini (Frankfurt School of Finance), Manju Puri (Duke and NBER)

Revise & Resubmit at the Journal of Finance (2025)

Stock prices of U.S. payment firms fall as a reaction to news about the Digital Euro, while those of Europeans rise. Bank stocks do not react. This emphasizes the medium-of-exchange function of CBDCs and points to a novel geopolitical dimension: enhanced autonomy in payments.

• "Buy Now, Pay Later" and Impulse Shopping, with  Valentin Burg (Humboldt University)

We find evidence consistent with behavioral explanations of "buy now, pay later" (BNPL) popularity. BNPL induces customers to purchases something when shopping visits are driven by cues like paid ads, occur at times of mental depletion, after casual and brief searches, or when shopping for hedonistic goods. However, we do not find that BNPL is pushed on vulnerable customers. There is some evidence for rational usage, though this is less robust. Ad-driven BNPL financing comes at the cost of substantially higher default rates.