One of the most striking developments brought about by digitalization is the rapid growth of online platforms. These range from e-commerce platforms, like eBay, Amazon, and Alibaba, which are now among the most prominent retail channels globally, and sharing platforms, such as Airbnb and Uber, to price comparison and hotel-booking platforms, like,, and

In this task, we analyze several open research questions related to the platform economy. Providing technology-enabled trust or quality- certification mechanisms is probably one of the main challenges and, at the same time, one of the major values added of platforms. Empirical studies identify the limitations of existing reputation and review systems, pointing out the importance of their design. To answer open questions on the design of such systems, we plan to expand recent work on price recommendation systems and study a model of a vertical relationship between many sellers and a single platform. In co-operation with a marketing provider that implements recommender systems for personalized marketing, we empirically study the impact of recommender systems on consumer behavior by utilizing large-scale field experiments. Further, we expand the limited literature on the effects of online rating systems regarding experience goods to online reviews on the consumption of credence goods and services, i.e. goods whose quality may not be observable even after consuming the good. Building on the limited research available on variety provision in markets with platforms, we extend existing models to encompass distinct participation and usage margins as well as search costs on the consumers’ side. We also study how platform design and listings of available options affect consumers’ search and preferences in e-commerce. The theoretical literature is now enriching basic models to account for multi-homing, i.e. the simultaneous use of competing platforms, but empirical work is lagging. Building on the empirical two-sided market literature, we empirically study how consumer multi-homing in platform markets matters when both sides are allowed to multi-home. Finally, we aim to contribute to the growing literature analyzing the impact of peer-to-peer marketplaces on the performance of traditional industries. To this aim, we study how the growth of Airbnb affected the hotel industry and rental prices.