engineering.uncertainty.type_a

Three distinct suites: educational examples on the calculator page, this legacy regression count (7/7 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. 6/6 golden · 3/3 CVP boundary · 7/7 invalid · 2/2 property · 2/2 metamorphic · 8/8 O3 · 4/4 cross-interface · 4/4 CVP contract. digest 091eb0d8d4cd. O2: mean / sample s / u_A = s/√n vs separate-module identities (≤2 ULP). Not GUM combination, not SEM product page, not Monte Carlo. ≤2 ULP vs O3 applies only to the published tabulated Type A vectors (Bessel, population, scale, constant, two-point, n=5, centered, default ddof). It is not a whole-domain sample-statistics guarantee.

• Golden (oracle-backed) 6 / 6
• CVP boundary 3 / 3
• Invalid input 7 / 7
• Property 2 / 2
• 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 Type A u_A = s/√n from a sample (Bessel ddof=1 default, population ddof=0) + O3 mpmath tabulated mean/s/u_A. CSV/JSON/array and sample alias.
• Assurance Engineering
• Deferred Not GUM RSS of several uᵢ, not expanded U=k·u_c, not Monte Carlo, and not a standalone SEM product page.

• release artifacts aligned PASS
• schema valid input executes PASS
• engine success output validates schema PASS
• schema rejects incomplete input PASS

Fingerprint sha256:abbbbc01e87248308a204e5238109d9a34f5b23acb2bb4d4f12993d725f5fe38

Input schema sha256:8cd2753b3d27d89ca2d63c7fc2d854103e5aa4db1d51e454eb70909d76d2ec82 · Output schema sha256:81b14f1a196e3f3448dddad91670038b910b106a21811ced1c5b0f62eb86b714 · 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-a

Engine

type-a

Engine build

2026-09-16

Evidence core

2026-09-16T21:07:40.795Z

Rendered

2026-09-16T22:38:08.851Z

Last reviewed

—

Assumptions

• Type A: u_A = s/√n from summarizeSample (ddof=1 default)
• Not GUM combination of several uᵢ
• Not Monte Carlo
• Independent repeated observations of one quantity

Limitations

• Type A from a sample — not GUM RSS of several uᵢ
• Not Monte Carlo
• ddof=1 requires n≥2