engineering.uncertainty.type_b_nu

Three distinct suites: educational examples on the calculator page, this legacy regression count (8/8 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

This calculator CURRENT · Public schema 1.0.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Verification revision 2026-09-16.o2-o3. Calculation version 1.0.0. CVP 1.0.0-proposed. 5/5 golden · 4/4 CVP boundary · 7/7 invalid · 3/3 property · 2/2 metamorphic · 8/8 O3 · 4/4 cross-interface · 4/4 CVP contract. digest 083418691428. O2: GUM G.4.2 ν = ½(u/σ(u))² vs separate-module identities (≤2 ULP). Not Type B u_B, not Welch ν_eff, not U=k·u_c. ≤2 ULP vs O3 applies only to the published tabulated G.4.2 vectors (GUM 25%, infinite, 10%, aliases, scale, σ(u)/u=0.5). It is not a whole-domain guarantee and does not cover Welch ν_eff or U=k·u_c.

• Golden (oracle-backed) 5 / 5
• CVP boundary 4 / 4
• Invalid input 7 / 7
• Property 3 / 3
• Metamorphic 2 / 2
• O3 high-precision 8 / 8
• Cross-interface 4 / 4
• CVP contract 4 / 4
• Interfaces PASS · UI (SSR) / REST / MCP
• Interface claim ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 1/1 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only.
• Verified scope GUM G.4.2 Type B degrees of freedom ν = ½(u/σ(u))², including σ(u)=0 → infinite, + O3 mpmath tabulated ν.
• Assurance Engineering
• Deferred Not Type B u_B from a half-width, not Welch ν_eff, not U = k·u_c, and not trapezoidal Type B.

• release artifacts aligned PASS
• schema output required declared PASS
• schema valid input executes PASS
• engine success output validates schema PASS
• schema rejects incomplete input PASS
• rest success payload validates schema PASS

Fingerprint sha256:3d40cf844dc08be261137b422291e061af52857add592a87446767d0900d3997

Input schema sha256:7b22b0d63d6e02d6665b31db6243dc6f28ac663223a6656463f1b12b0dfd2817 · Output schema sha256:cf26d94dacd5758ad6abd0a6c918c65e209e07652decb2eba100305caf88d321 · 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.

Tool

type-b-nu

Engine

type-b-nu

Engine build

2026-09-16

Evidence core

2026-09-16T21:07:40.795Z

Rendered

2026-11-10T05:18:41.780Z

Last reviewed

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Assumptions

• JCGM 100:2008 G.4.2: ν = ½ (u/σ(u))²
• σ(u)=0 → ν is infinite (REST returns nu=null, infinite=true)
• Not Type B u_B from a half-width, not Welch ν_eff, and not U = k·u_c

Limitations

• GUM G.4.2 ν from stated u and σ(u) — not Type B u_B = a/√3
• Not Welch–Satterthwaite ν_eff from several u_i, ν_i
• Not expanded U = k·u_c
• Does not take half-width a