Jörn Grahl (University of Cologne): 

"How do recommender systems influence consumer behavior? Evidence from a randomized controlled field experiment"

Thursday, November 26, 02:00pm - 04:00pm (WiSo Building, Room 410) 

Abstract:

Recommender systems have become essential ingredients of digital platforms. They mine data in order to suggest products, services, or even friends. Recommenders are popular. You would be hard-pressed to find a succesful digital platform without one, but researchers are still struggling to identify causal relationships between recommendations and consumer behavior. Several fundamental questions are not yet fully explored: How do recommender systems influence economic decisions like conversion, sales, or product choice? Do recommenders have a systematic influence on product choice, i.e., do they lead consumers away from established top-sellers toward their own preferences and niches? 

To answer these questions, I have designed and implemented the recommender system for the bookseller ebook.nl. The system is based on collaborative filtering (similar to Amazon.com: "Customers who bought this item, also bought:"). We are currently running a large randomized controlled experiment on all visitors of the shop. We randomly assign visitors to a "treatment group" and a "control group". The treatment group is exposed to recommendations whereas the control group is not.

In this presentation I will (a) present the current status of the project, (b) discuss first results, and (c) explain how the project fits into my overall research agenda.