Verification
8/8 calculation tests · Production surface contract 4/4
- Golden tests 0 / 0
- Boundary tests 5 / 5
- Property tests 3 / 3
- Production surface contract 4 / 4
}
- Engine tested Yes
- Source checked Yes
- Artifact integrity PASS
- Production attestation Embedded snapshot: unpublished · Build schema 1.0.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status STALE (1 capability; 156 remain CURRENT) @ 2026-09-14T03:54:53.650Z
- Semantic contract PASS
- Evidence attested at 2026-09-14T00:43:05.498Z
- Last production check 2026-09-14T00:43:05.498Z
- Public / cache —
- Origin —
- Supplemental domain review Not performed
- Named expert review Not performed
- release artifacts aligned PASS
- schema valid input executes PASS
- engine success output validates schema PASS
- schema rejects incomplete input PASS
Fingerprint sha256:8d243ca0f5a4bf0c739a025de5a11affab29de7f59d268d598be726eee27e6b1
Input schema sha256:b74f8e2c292e62d54897cacc1e631a0438de139567fa28f0fb73547c7486a02d · Output schema sha256:06e1c702a162f03549bb81425703a25b0533e655639ef73fbbecca08960e583c · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write
(published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.
Engine identity and declared limitations.
- Tool
- precision-uncertainty
- Engine
- precision-uncertainty
- Engine build
- 2026-09-15
- Evidence core
- 2026-09-15T23:14:39.081Z
- Rendered
- 2026-09-15T23:38:12.910Z
- Last reviewed
- —
Assumptions
- ISO 21748: u = √(s_L² + s_r²/n) of a mean of n replicates from stated precision components. n≥2.
- s_r and s_L are ≥ 0. Both zero is valid (u = 0).
- Not R = 2.8·s_R, not Type A from a sample, and not U = k·u.
Limitations
- Takes stated s_r, s_L, and n≥2 — not a sample of observations
- n=1 is rejected so this cannot wrap s_R
- Not ISO 5725 R = 2.8·s_R and not Type A u_A = s/√n from values
- Does not compute expanded U = k·u
Sources
Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.
- ISO 21748 — Guidance for the use of repeatability, reproducibility and trueness estimates in measurement uncertainty evaluation — Uncertainty of a mean from precision components
Supports: u = √(s_L² + s_r²/n) is the standard uncertainty of a mean of n replicates when s_r and s_L are already stated.
- ISO 5725-1 — Accuracy (trueness and precision) of measurement methods and results — Repeatability s_r and reproducibility s_R
Supports: s_r and s_L are the same precision components used for R = 2.8·s_R. This page reports u of a mean, not R.
Published checks
Golden, boundary, and property cases included in this evidence build.
| ID | Kind | Status | Detail |
|---|
boundary-pu | boundary | pass | Expected n=4 · u=5 · Actual n=4 · u=5 · s_r=8 · s_L=3 |
boundary-pu-zero-l | boundary | pass | Expected u=4 · Actual n=4 · u=4 · s_r=8 · s_L=0 |
boundary-pu-zero | boundary | pass | Expected u=0 · Actual n=4 · u=0 · s_r=0 · s_L=0 |
boundary-pu-n1 | boundary | pass | Expected VALUE_OUT_OF_RANGE · Actual VALUE_OUT_OF_RANGE |
boundary-pu-missing | boundary | pass | Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT |
property-pu | property | pass | 5 |
property-pu-zero-l | property | pass | 4 |
property-pu-alias | property | pass | 5 |
