We analyze the problem of a buyer who purchases a long-term project from one of several suppliers. A changing state of the world influences the costs of the suppliers. Complete contracts conditioning on all future realizations of the state are infeasible. We show that contractual incompleteness...

We analyze the problem of a buyer who chooses a supplier for a long-term relationship via an auction. The buyer lacks commitment to not renegotiate the terms of the contract in the long run. Thus, suppliers are cautious about the information revealed during the auction. We show theoretically and...

We analyze the problem of a buyer who purchases a long-term project from one of several suppliers. A changing state of the world influences the costs of the suppliers. Complete contracts conditioning on all future realizations of the state are infeasible. We show that contractual incompleteness...

Bidding in first-price auctions crucially depends on the beliefs of the bidders about their competitors' willingness to pay. We analyze bidding behavior in a first-price auction in which the knowledge of the bidders about the distribution of their competitors' valuations is restricted to the...

We test the importance of social norms for market interactions associated with negative real-world externalities in a large-scale experiment with a heterogeneous population sample from Germany. The majority of experimental participants refuses to trade, thus behaving in a moral way. Our data...

Herdenimmunität, oder zumindest eine hohe Durchimpfung, ist ein Ziel der Impfungen gegen COVID-19. Dieses soll möglichst schnell erreicht werden, um weitere Ansteckungswellen zu verhindern und auch die Ausbreitung stärker ansteckender Varianten zu bremsen. Bisher war die Impfstoffmenge ein...