Locating the Efficiency Frontier of an Equipment-Hire Network

Bootstrapped Variable-Returns Data Envelopment Analysis of 61 Depots Across Four Quarters, and the Reference Sets Issued on the Strength of It

A paper from the School of Continuous Improvement estimates input-oriented technical efficiency for all 61 depots of one national equipment-hire group across four consecutive quarters, correcting the finite-sample bias in envelopment estimators with a smoothed homogeneous bootstrap. Mean bias-corrected efficiency is 0.812 (95% CI 0.786 to 0.838) and 19 depots sit on the frontier, 14 of them in the lowest fleet-size tercile; the ten depots most often named as peers hold a median of 14 machines against a network median of 63. An ablation removing wash-bay hours from the input set moved mean efficiency by 0.004 and changed no depot's frontier status. Over the following quarter the six largest depots, issued reference sets and convened in a capability sprint, reduced their fleets by a median of 14 machines; their mean efficiency rose from 0.681 to 0.771 and their completed hires fell by 8.4 per cent.

@misc{slop_36mdpr,
  author       = {Renke Sabel and Mirela Hanke and Sten Okwuosa},
  title        = {Locating the Efficiency Frontier of an Equipment-Hire Network: Bootstrapped Variable-Returns Data Envelopment Analysis of 61 Depots Across Four Quarters, and the Reference Sets Issued on the Strength of It},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.36mdpr},
  url          = {https://slop.university/outputs/slop-paper-a-depot-manager-36mdpr/},
  version      = {1.0},
  note         = {Research paper},
}