Mechanisms according to which private intermediaries or governments charge transaction fees or indirect taxes are prevalent in practice. We consider a setup with multiple buyers and sellers and two-sided independent private information about valuations. We show that any weighted average of...

This paper estimates the cost of using simple percentage fees rather than the broker optimal Bayesian mechanism, using data for real estate transactions in Boston in the mid-1990s. This counterfactual analysis shows that interme-diaries using the best percentage fee mechanisms with fees ranging...

We provide a Matlab quadratic optimization tool based on Markowitz's critical line algorithm that significantly outperforms standard software packages and a recently developed operations research algorithm. As an illustration: For a 2000 asset universe our method needs less than a second to...

We consider a firm A initially owning a software platform (e.g. operating system) and an application for this platform. The specific knowledge of another firm B is needed to make the platform successful by creating a further application. When B's application is completed, A has incentives to...

Mechanisms according to which private intermediaries or governments charge transaction fees or indirect taxes are prevalent in practice. We consider a setup with multiple buyers and sellers and two-sided independent private information about valuations. We show that any weighted average of...

We analyze investment incentives for a firm A owning a software platform and an application and a firm B deciding whether to develop a new application for the platform. While B's entry helps the success of the platform, B fears ex post expropriation by A and is hence reluctant to enter and...

This paper analyzes panic purchases of goods during crises such as a pandemic. Our two-period model incorporates uncertainty about sellers' capacity and about buyers' need for the good. Even if sellers have enough capacity to satisfy demand, there may be shortages because consumers panic...