No Change in the Tin

A Randomised Crossover Trial of Float and Price Roundness at 58 Roadside Honesty-Box Stalls

A research poster from the School of Emergent Priorities randomises the change float and the unit price at 58 roadside honesty-box stalls across four shire districts, in a two-by-two crossover covering 464 stall-weeks and 21,318 items removed. Payment shortfall falls 17.5 percentage points between the worst and best cells (22.6 per cent to 5.1 per cent; 95% CI 13.6-21.4), of which a coin float carries 11.8 points and whole-dollar pricing 6.3; stall identity explains 7 per cent of what remains, and 21 of the 24 stalls the districts' published honesty index lists as high trust keep a permanent float.

@misc{slop_pfhong,
  author       = {Kwame Lindqvist and Fenna Okoro and Lindiwe Achterberg},
  title        = {No Change in the Tin: A Randomised Crossover Trial of Float and Price Roundness at 58 Roadside Honesty-Box Stalls},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.pfhong},
  url          = {https://slop.university/outputs/slop-poster-roadside-honesty-boxes-pfhong/},
  version      = {1.0},
  note         = {Research poster},
}