I discuss private and central-bank-issued digital currencies, summarizing my prior research. I argue that prices of private digital currencies such as bitcoin follow random walks or, more generally, risk-adjusted martingales. For central bank digital currencies, I argue that they enhance the...

Tiny changes in the American monetary policy can have dramatic effects on the rest of the world because of dollar's double role of national and international currency. This is the Triffin dilemma. The paper shows how it works through three examples: price of commodities, dollarization, and the...

This paper seeks to inform about a feature of monetary policy that is largely overlooked, yet occupies a central role in modern monetary and financial systems, namely central bank collateral frameworks. Their importance can be understood by the observation that the money at the core of these...

Die Staatsanleihekäufe der EZB sind zu einem Fall für das Bundesverfassungsgericht geworden. Die Autoren des IW Köln argumentieren, dass das Outright-Monetary-Transactions-Programm noch innerhalb der Grenzen des EZB-Mandats liegt, aber wegen seiner Nachteile nur temporär eingesetzt werden...

Central banks have responded with exceptional vigour to the crisis by using their traditional interest-rate tools to their limits and deploying a wide range of unconventional measures. This paper documents these responses in a systematic way, reviews the evidence about their impact, and...

Terra, the third largest cryptocurrency ecosystem after Bitcoin and Ethereum, collapsed in three days in May 2022 and wiped out $50 billion in valuation. At the center of the collapse was a run on a blockchain-based borrowing and lending protocol (Anchor) that promised high yields to its...