At a glance
An unusual result should prompt an investigation, not automatic deletion. It may reveal a preparation error, a measurement problem or genuine material variation relevant to production.
Key points
- Removing a low result because it looks inconvenient biases the reported performance.
- Retain raw results and record the reason for any exclusion.
- A credible technical file shows how uncertainty was handled.
Technical context #
Removing a low result because it looks inconvenient biases the reported performance. Conversely, a documented equipment malfunction may justify excluding a measurement under the agreed method. The decision needs evidence and a consistent rule.
What to measure and document #
Retain raw results and record the reason for any exclusion. Review specimen identity, conditioning, test setup and failure observations. Where a retest is justified, state whether the original result remains part of the report and why.
Implications for development and specification #
A credible technical file shows how uncertainty was handled. For buyers, unexplained perfect consistency can be less informative than a transparent account of variation. The objective is an honest estimate of performance, not the most flattering average.
Related reading and evidence limits #
General engineering-statistics guidance; not a WPC product standard. Use the linked work as related reading. The practical checks above are editorial recommendations, not reported test results or a substitute for product qualification.
Evidence checklist for outliers in wpc testing: investigate before excluding
| Review step | Evidence to retain |
|---|---|
| Material and geometry | Exact specimen or product identity |
| Verification | Method, conditions and individual observations |
| Decision | Approved scope and documented limitations |
Common questions
What evidence is needed for outliers in WPC testing: investigate before excluding?
Retain raw results and record the reason for any exclusion. Review specimen identity, conditioning, test setup and failure observations. Where a retest is justified, state whether the original result remains part of the report and why.
Question permalink ↗Sources & further reading
- NIST engineering statistics handbook ↗NIST · web · 2026-10-14
Cite this page
NFC & WPC Knowledge Reference. “Outliers in WPC testing: investigate before excluding” Version 1. Updated 2026-10-15. https://woodplasticcomposite.net/guides/outliers-in-wpc-testing-investigate-before-excluding/
Review & revision
AI-assisted English editorial draft. Human technical review has not been recorded.. Prepared with AI assistance. Editorial policy.
New focused technical draft; not a product certification or production recipe. General material information is not product certification.
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