  In this paper, we analyze the worst case efficiency loss of online platform
designs under a networked Cournot competition model. Inspired by some of the
largest platforms in operation today, the platform designs that we consider
examine the trade-off between transparency and control. Our results show that
open access designs incentivize increased production towards perfectly
competitive levels and limit efficiency loss, while controlled allocation
designs lead to producer-platform incentive misalignment, resulting in low
participation and unbounded efficiency loss. We also show that discriminatory
access designs balance transparency and control, achieving the best of both
worlds by maintaining high participation rates while limiting efficiency loss.
