Berlin IO Day

Speakers & papers

Jacopo Bizzotto (Oslo Metropolitan University):

Collusion without Patience
(joint with Toomas Hinnosaar)
PDF (PDF, 0.54 MB)
Abstract: Tacit collusion is usually linked to repeated interactions between patient firms. We show that it can also arise in a one-shot duopoly. When firms choose capacities and face outsourcing contracts with minimum order quantities, gaps in feasible outputs allow commitment not to sell intermediate quantities. For a range of parameters, there exists a collusive equilibrium in which both firms produce less and earn more than under competition. Three other equilibria can also arise: competitive, leadership, and miscoordination. We then extend the model to general two-sided limited commitment and show that it yields the same set of equilibria.

Ioana Chioveanu (University of Nottingham):

Price Discrimination Under Asymmetric Access to Consumer Data
PDF (PDF, 0.79 MB)
Abstract: A platform-affiliated retailer competes in prices with third-party sellers over two periods. After the first period, the affiliate has access to market-wide purchase data and an informational advantage. Third-party sellers either do not obtain data (exclusive data use) or obtain only data on their own past customers (shared data use). Data access enables price discrimination by consideration in the second period. With exclusive data use, price discrimination benefits all retailers compared to uniform pricing. The affiliate benefits more than third-party sellers. However, third-party sellers’ lack of data limits the extent to which the affiliate can use its superior information. With shared data use, all retailers benefit equally from price discrimination compared to uniform pricing. Mandatory sharing of past customer data does not harm the affiliate, although it reduces its informational advantage, and benefits third-party sellers. However, while leveling the playing field on the supply side, it harms consumers.

Ying Fan (University of Michigan):

Subsidy Design, Price Setting, and Quality Provision: A Study of Medicare Advantage
(joint with Colleen Carey and Yiyi Zhou)
Abstract: Public–private partnerships often feature imperfect competition, leading to distortions in prices and quality. This paper studies subsidy design in the Medicare Advantage market, focusing on the 2012 Quality Bonus Program, which linked key subsidy parameters to plan quality. We develop a stylized model showing that quality-linked subsidy pass-through can mitigate distortions in both pricing and quality incentives. We then estimate a structural model of demand and supply using plan-level and individual-level data from 2010--2017. We find that quality-dependent subsidies raise quality and welfare, and that linking the rebate rate to quality delivers the largest efficiency gains without increasing government spending.

Max J. Pachali (Tilburg University):

TBA

Amparo Urbano (University of Valencia):

Strategic Multiproduct Trading of Indivisible Goods
(joint with Iván Arribas)
PDF (PDF, 0.55 MB)
Abstract: This paper analyzes markets in which indivisible goods are sold by multi-product firms to a finite set of heterogeneous buyers, who may have non-monotonic preferences over bundles of products. We prove the existence of efficient subgame perfect equilibrium by formulating the problem as the linear programming relaxation of the standard Package Assignment Problem. Specifically, we show that the projection of the dual’s Pareto efficient frontier on the sellers’ coordinates characterizes a class of efficient equilibrium prices, the Strong equilibrium prices.

Registration

If you would like to attend the workshop, please send an e-mail with full name and affiliation before March 9, 2026 to Sibylle Kremser at skremser@diw.de.

Host of the 20th Berlin IO Day

Many thanks to Andreas Asseyer from Freie Universität Berlin and Daniel Guhl from ESMT Berlin!

About Berlin IO Day

The Berlin IO Day is a one-day workshop supported by the Berlin's leading academic institutions, including DIW Berlin, ESMT Berlin, Freie Universität Berlin, Humboldt-Universität zu Berlin, and Technische Universität Berlin which takes place twice a year, in the Spring and in the Fall.

For each Berlin IO Day, we will invite four or five speakers to present their recent work on a variety of IO topics, followed by a general discussion. The aim is to create an international forum for high quality research in Industrial Organization in the heart of Berlin, one of Europe's most vibrant and intellectually lively cities.

Organizers:

• Tomaso Duso, Jo Seldeslachts, Hannes Ullrich (DIW Berlin)
• Michał Grajek, David Ronayne (ESMT Berlin)
• Andreas Asseyer (Freie Universität Berlin)
• Daniel Guhl, Daniel Klapper, Roland Strausz (Humboldt-Universität zu Berlin)
• Radosveta Ivanova-Stenzel (Technische Universität Berlin)