01 · Purpose
Why and when to use it
Use it before collection or classification, especially when staff interpret a requirement differently.
Who takes part?
The measurement owner works with people who understand the process and the recorded data. Statistical or measurement-system decisions should involve someone able to check the assumptions and study design.
02 · Application
How to apply it
Start with an agreed measurement purpose, explicit units and trustworthy observations. Identify missing cases and assumptions before calculating.
- Name the concept and why it needs measuring.
- Define the unit of observation and the event or characteristic.
- Specify the method, data fields and calculation.
- Set boundary rules, time basis and exceptions.
- Have different people apply the definition to the same cases and resolve disagreements.
03 · Example
A worked measurement example
Original fictional teaching example. Small datasets illustrate the method; they are not proposed as sufficient study sizes. Supplied parameters are assumptions, not estimates from a real process.
| Definition element | Dispatch example |
|---|---|
| Unit | One eligible order with an agreed promised dispatch date |
| Late rule | Carrier handover date is later than promised dispatch date, using the warehouse’s local calendar |
| Missing timestamp | Unknown, flagged separately |
| Split shipment | Use final handover date if the requirement is complete-order dispatch; confirm this rule with the customer |
04 · Interpretation
What the result tells you
The split-shipment rule can materially change the result. Agreement on that rule is necessary before comparing shifts or periods.
Completion check: A tested instruction that enables consistent observation or calculation.
05 · Judgement
Mistakes and limitations
A definition can be consistent yet measure the wrong outcome. Check customer relevance as well as repeatability; distinguish dispatch from customer delivery.
07 · Reading
Sources and further reading
The tool list follows the accepted LeanTrainingLab overview and its reference to Six Sigma+Lean Toolset, second edition (Lunau, editor; Springer, 2013). The book chapters were not available for direct review during this build. Explanations, examples and worksheets are original teaching material. Further reading supplies professional background; local conventions are stated explicitly.