Sold Elsewhere

Stale Cross-Listings as a Cross-Platform Externality of Seller Multi-Homing

A paper from the School of Continuous Improvement matches 2,217 bicycle parts cross-listed on two rival classified marketplaces in one regional city and follows each pair to its sale, finding that the copy left behind on the smaller, free platform outlives a sale on the larger one by a median of twelve days, while the reverse residue clears in two. An accounting identity ties the asymmetry to the 18.4% of the smaller platform's enquiries that reached items already sold elsewhere, and a staggered liveness prompt cut that share by 11.8 percentage points without measurably reducing cross-listing.

@misc{slop_qy2jd1,
  author       = {Bram Ntuli and Joost Nwosu},
  title        = {Sold Elsewhere: Stale Cross-Listings as a Cross-Platform Externality of Seller Multi-Homing},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.qy2jd1},
  url          = {https://slop.university/outputs/slop-paper-stale-cross-listings-as-qy2jd1/},
  version      = {1.0},
  note         = {Research paper},
}