The Constant Outlived the Cup

A Calibration Audit of a Self-Serve Frozen-Yogurt Chain's Programmed Tare Weight Across Three Supplier Cohorts, and What Its Daily Scale-Variance Report Never Flagged

A paper from the School of Continuous Improvement audits a self-serve frozen-yogurt chain's programmed tare constant against the empty-cup stock two supplier changes have since put in circulation, sampling 960 cups across 24 stores. The legacy supplier's cups match the register's 14.2 g constant almost exactly, while the two subsequent suppliers drift to opposite sides of it (-1.57 g and +1.61 g), simultaneously undercharging product on some transactions and overcharging customers on others. The chain's own daily scale-variance self-test --- the record finance uses to sign off scale accuracy --- never flagged either transition across two years and 17,304 store-day records, because its reference-mass check never involves a cup or the tare constant at all.

@misc{slop_ntc5qi,
  author       = {Sten Okwuosa and Marit Osayande and Ingeborg Nwachukwu},
  title        = {The Constant Outlived the Cup: A Calibration Audit of a Self-Serve Frozen-Yogurt Chain's Programmed Tare Weight Across Three Supplier Cohorts, and What Its Daily Scale-Variance Report Never Flagged},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.ntc5qi},
  url          = {https://slop.university/outputs/slop-paper-a-self-serve-frozen-yogurt-ntc5qi/},
  version      = {1.0},
  note         = {Research paper},
}