{
  "id": "social-lsoa-exposure-2026-10-10-v1",
  "auditedAt": "2026-10-10T17:47:34.280897+00:00",
  "exposureGatePassed": false,
  "predictionLayerAvailable": false,
  "phase6Status": "Pipeline implemented and fixture-tested; real LSOA frequency modelling blocked by exposure",
  "profileRows": 33755,
  "eligibleFrequencyRows": 0,
  "inventory": [
    {
      "input": "Social profiles",
      "status": "available",
      "detail": "33,755 exact-code LSOA21 profiles; 2021 education and 2025 deprivation. Descriptive only.",
      "artifact": "public/research/social-factors/deciles-v1/feature-audit.json",
      "sha256": "7f64c844117fe0e1c58e0c43a4627f2d7afe013f52cd73527f92d05fa65700ee"
    },
    {
      "input": "Collision records",
      "status": "partial",
      "detail": "Archived STATS19 records contain positions and published LSOA codes; unique event-to-LSOA21 allocation and positional audit remain to be run with compatible boundaries.",
      "artifact": "public/research/parking/v1/lsoa-coding-coverage.csv",
      "sha256": "5875148ce6d31593ac6635aaa76cd423b2d425883c7c1f4b62409bab45d18a0d"
    },
    {
      "input": "LSOA21 allocation boundaries",
      "status": "missing",
      "detail": "Full compatible polygons not loaded into this exposure pipeline; population centroids are display-only.",
      "artifact": null,
      "sha256": null
    },
    {
      "input": "Historical all-road segments",
      "status": "missing",
      "detail": "The 2026 road-network snapshot used elsewhere is not a year-matched 2018\u20132025 network.",
      "artifact": null,
      "sha256": null
    },
    {
      "input": "Major-road flow/link matching",
      "status": "partial",
      "detail": "DfT publishes major-road link estimates; no audited link-to-LSOA mileage allocation is present.",
      "artifact": null,
      "sha256": null
    },
    {
      "input": "Minor-road AADT",
      "status": "missing",
      "detail": "DfT count points cover a sample. Unsampled-road estimates and independent holdout validation are absent.",
      "artifact": null,
      "sha256": null
    },
    {
      "input": "Road-class \u00d7 rurality totals",
      "status": "missing",
      "detail": "No matched authority/year/stratum reconciliation set is present.",
      "artifact": null,
      "sha256": null
    },
    {
      "input": "Exposure uncertainty",
      "status": "missing",
      "detail": "No segment-level uncertainty bounds or independent traffic validation set is present.",
      "artifact": null,
      "sha256": null
    }
  ],
  "gates": [
    {
      "name": "Complete intended-road network",
      "passed": false,
      "reason": "No matched complete historical segment inventory"
    },
    {
      "name": "Independent traffic validation",
      "passed": false,
      "reason": "No validated unsampled minor-road allocation"
    },
    {
      "name": "Authority/stratum reconciliation",
      "passed": false,
      "reason": "No compatible year \u00d7 road class \u00d7 rurality totals"
    },
    {
      "name": "Collision allocation",
      "passed": false,
      "reason": "Compatible polygon and positional audit pending"
    },
    {
      "name": "Exposure uncertainty",
      "passed": false,
      "reason": "No validated segment uncertainty scenarios"
    }
  ],
  "assumptionsRejected": [
    "Population as vehicle-miles",
    "Zero exposure for missing flow",
    "Count-point totals as a complete minor-road network",
    "Redistributing authority miles by social bands",
    "Backdating the 2026 road network"
  ],
  "sources": [
    {
      "publisher": "DfT",
      "url": "https://roadtraffic.dft.gov.uk/count-points",
      "checkedAt": "2026-10-10T17:47:34.280915+00:00",
      "finding": "Major-road links and a sample of minor-road locations."
    },
    {
      "publisher": "DfT",
      "url": "https://roadtraffic.dft.gov.uk/downloads",
      "checkedAt": "2026-10-10T17:47:34.280918+00:00",
      "finding": "Individual link/small-area estimates have greater uncertainty and may use older counts."
    }
  ],
  "nextAction": "Acquire a year-matched network and transport-only minor-road traffic model with independent holdouts, then run this exposure gate before opening a separate LSOA outcome study.",
  "majorRoadOption": "Possible only as a separate version after matching collision events and vehicle-miles to exactly the covered major-road links; not implemented as an all-road proxy.",
  "software": {
    "shapely": "2.2.0"
  },
  "codeSha256": "0b25d7bc8a0002f47bf8d63e448079a87872675d7993448873be1703805bc7cf"
}