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Department of Economics

Seminar on "Should platforms be allowed to sell on their own marketplaces?"

Speaker Dr. TAT-HOW TEH
Postdoctoral Research Fellow
Department of Economics
National University of Singapore (NUS) 
Date 12 October, 2020 (Monday)
Time 2:00pm-3:30pm
Venue ZOOM Meeting
(Meeting ID: 99058093002)

A growing number of platforms such as those run by Amazon, Apple and Google operate in a dual mode: running marketplaces, at the same time as selling products on them. We build a model to explore the implications of this controversial practice. We show that while banning the dual mode benefits third-party sellers, it often results in lower consumer surplus or total welfare, even after allowing for innovation by third-party sellers, and imitation and self-preferencing by the platform. Instead, policies that prevent platform imitation and self-preferencing always lead to better outcomes than an outright ban on the dual mode.


Dr.TEH joined the National University of Singapore (NUS) in 2019 as a Postdoctoral Research Fellow in the Department of Economics. He studied at NUS for PhD in economics (2015-2019). His research interests are Multi-sided Platforms, Industrial Organization, Economics of Networks, and more generally Applied Microeconomic Theory.