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labplatform

Project F · The trust layer above every laboratory
06 / 07

Compares laboratories against each other, quantifies the uncertainty of every result, and detects measurement-system drift.

4sites · 3 countries200measurement jobs3,610results ingested48calibration verifications16tests11 pptechnical report
Problem

The problem

Two laboratories measure the same cable. Roth says 7.907 dB; Changzhou says 7.923 dB. Is that a problem? With only the two numbers, the question is unanswerable — and organisations answer it anyway, with meetings.

The correct answer requires each number to carry its uncertainty budget, so the comparison becomes a statistic instead of an argument: the sites differ by 0.016 dB against an expanded uncertainty of the difference several times larger — not distinguishable. And beyond any single comparison: is a site drifting month over month, which calibration event caused it, and which already-issued results does a failed verification put in doubt?

System

What was built

A metrology platform over any number of labauto laboratories — one canonical data model, and the full apparatus of interlaboratory comparison on top.

Sealed archives from every siteraw files, sidecars, manifests — refused jobs included, because a network that cannot see its refusal rate cannot manage it
Canonical modelsites · instruments · calibrations · samples · procedures · runs · results · traces · verifications · events
Uncertainty budgetsrepeatability, reproducibility, calibration, fixture, instrument, environment, noise, resolution — GUM-combined, stored with every result
Round robinE_n · ζ · z, Cox consensus
R&RISO 5725-2 nested ANOVA
Control chartsShewhart + EWMA, WE rules
Drift detectiontrend, change point, EWMA — with root cause attributed against calibration, environment and operator records
Trust cards + evidence packsvalue, budget, provenance, standing in its round, status — and the suspect list when a verification fails
Takes
  • labauto archives from any number of sites
  • The circulating artefact's round-robin schedule
  • Check-standard certificates for calibration verification
Produces
  • An uncertainty budget on every scalar result
  • Compatibility statements per site, per quantity, per round
  • Repeatability, intermediate precision and reproducibility for the network
  • Drift alerts with attributed root cause
  • Retrospective suspect lists after a failed verification
  • A self-contained dashboard
Engineering

The hard part

The uncertainty budget is the engineering heart, and its hardest entries are the ones naive budgets get wrong. Reflection quantities cannot inherit the transmission calibration's bound: a −27 dB return loss measured against a −52 dB residual directivity floor carries close to a decibel of uncertainty, and the budget says so instead of flattering itself. Reproducibility must not double-count what calibration already covers, so only the between-round variance the calibration bound cannot explain enters. Every result is referred to 23 °C with the temperature coefficient's own uncertainty propagated.

The payoff is the demonstration's planted fault: one site's setup degrades quietly from round 7. The platform sees it on the site's verification chart three rounds before the laboratory's own gate refuses to measure — and when the verification finally fails, it walks the chain backwards and names the five results taken under that calibration as suspect. Detection, then retrospective traceability.

Per-site longitudinal series with fitted trend, change point and EWMA signals.
FIG. 01  The planted fault, caught early: drift analysis on each site's artefact series — trend, change point and EWMA — with the root cause attributed to the records, not guessed.
Evidence

Checked against ground truth

Statistics checked against the standards' own worked values; the network checked by simulating one with a known fault.

What was checkedResult
E_n against Cox consensus, IL @ 600 MHz, all sites|E_n| ≤ 0.22 — all compatible
Nested ANOVA (ISO 5725-2), Cochran + Grubbs screeningmatches worked reference values
Control chartsphase-I/II split, Western Electric rules on rational subgroups
Planted degradation at round 7flagged 3 rounds before the gate refused
Failed verification → suspect resultsthe 5 affected runs identified
Network scale exercised4 sites · 10 rounds · 200 jobs · 3,610 results
Uncertainty budget split per site and site values against the consensus with expanded uncertainty.
FIG. 02  Why Roth is trusted more than Kitzingen: the budgets differ, and the comparison uses them.
E_n scores against frequency for each site.
FIG. 03  Compatibility across the band: E_n per frequency — agreement is not a single-number claim.
Declared limits

What it does not claim

From the report's own limitations section:

  • The four laboratories are simulated (labauto's instrument models); the statistics are exercised on data whose truth is known.
  • Mismatch between test-port and cable impedance is declared unevaluated in the budget, not silently absorbed.
  • Root-cause attribution is correlational against the records — it names the coinciding change, not a proven mechanism.
Context

Where it sits in the toolchain

This is what labauto's sealed archives exist for: the platform ingests any number of them into one comparable whole. Its budgets set the default cable uncertainties in linktwin's Monte Carlo, and its trust cards are the provenance a link verdict can cite when someone asks "measured where, under what?"

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