Assumptions and method
Defects and defective units are different. Removal efficiency only covers defects found so far.
Test a scenario
Use the result in a decision
Agree acceptance criteria and distinguish variation from a meaningful signal.
Defects and defective units are different. Removal efficiency only covers defects found so far.
Set a baseline and change one assumption to compare outcomes.
A worked example
Follow the fixed teaching example
- Defects per unit = 24/600 = 0.04.
- Observed removal efficiency = 18/(18 + 6) × 100 = 75%.
These illustrative inputs describe a project scenario, not a published benchmark. All monetary inputs use the same currency and price basis.
- Observed defects
- 24
- Units inspected
- 600
- Defects removed before delivery
- 18
- Defects found after delivery
- 6
- Defects per unit
- 0.04
- Observed removal efficiency
- 75 %
Interpret the output only within the assumptions above. Changing the inputs changes the result; it does not validate the inputs.
Source & credit
Standard estimating practice; the cited guide documents use rather than claiming invention.
GAO: Cost Estimating and Assessment Guide
This is independently written code and explanation of the underlying method. The linked publication, its diagrams and its trademarks remain its owner’s material; no permission to reuse them is implied.