The Terminal Kept the Score

Validating a Cafe Franchise's Point-of-Sale Tip-Suggestion Screen Dwell Time as a Per-Outlet Friendliness Proxy Against Realised Tip Percentage

A paper from the School of Continuous Improvement validates a cafe franchise's point-of-sale "friendliness score" --- the seconds a terminal's default tip-suggestion screen holds a customer's attention, folded into quarterly outlet-manager reviews --- against realised tip percentage across 214,612 transactions and 44 outlets over five months. Prompt dwell time shows a negligible, non-significant association with realised tips (r = 0.06), a null that survives an ablation removing terminal hardware generation as a covariate, while the franchise's existing quarterly service-audit rating retains a moderate positive correlation in every region (r = 0.27-0.36). Dwell time instead varies threefold across the network's three terminal hardware generations, tracking equipment age rather than staff behaviour.

@misc{slop_27mugw,
  author       = {Mirela Hanke and Torun Ezeigwe and Marek Solheim},
  title        = {The Terminal Kept the Score: Validating a Cafe Franchise's Point-of-Sale Tip-Suggestion Screen Dwell Time as a Per-Outlet Friendliness Proxy Against Realised Tip Percentage},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.27mugw},
  url          = {https://slop.university/outputs/slop-paper-an-instrument-validation-study-27mugw/},
  version      = {1.0},
  note         = {Research paper},
}