Library · Guides
Verifying a figure
Three independent checks: that a document is the one published, that a figure came from the inputs its record names, and that the engine still produces it from them. Verifiers have read-only access to all three; the first is open to anyone.
Is this the briefing that was published?
Anyone can do this, without an account.
- 1
Compute the file's SHA-256
On macOS or Linux,shasum -a 256 briefing.pdf; on Windows,certutil -hashfile briefing.pdf SHA256. - 2
Compare it with the register
Scan the QR code on the cover, or find the report id in the transparency record. The two values must match exactly.
Where did a figure come from?
Signed in as a verifier, a reviewer or NCEL.
- 1
Open the figure's lineage
From the footnote, from “How this was made” under any figure, or by pasting a lineage id into search (Ctrl or ⌘ K). - 2
Read what it names
The monthly returns, the factor set, the parameters, the constants, the fluid properties, the engine version and the random seed, with a SHA-256 over all of them. - 3
Follow it back
Each return links to the submission it came from and the file as filed, with that file's own SHA-256.
Does the engine still produce it?
Reproducibility, on a schedule and on request.
- Scheduled
- A sample of stored figures is re-run from their lineage every day; the results are in the transparency record.
- On a briefing
- “Verify this briefing” checks both files against their hashes and reports every figure's latest re-run; “Re-run every figure now” re-runs them all.
- What counts as reproduced
- The recomputed value equals the stored one at storage precision. A figure is reproduced by the method that made it, so a later factor set never makes an older figure fail.
Independence. The platform provides evidence; it does not certify itself. Independent assurance rests with accredited verifiers, so no single institution is both author and verifier of a regulatory figure.