 SCORECARD ARENAS DISCOVERY FOUNDATIONS FOR AGENTS 

← HOUSING / US VINTAGE 7399c8f1 PENDING

Middle Atlantic · 6M

On 4 August 2026 we predicted Middle Atlantic house prices would be 2.00% higher by November 2026.

Our stated range was 410.897 to 435.192 — if the method works as intended, the true figure lands inside it about 95% of the time. Verdict due the first FHFA release covering November 2026, when the official figure is published. It has not been graded yet, and nothing on this page can change what was written above.

01 / WHAT WAS LOCKED

FORECAST · INDEX LEVEL 422.870

CHANGE FROM BASE +2.00%

95% INTERVAL 410.897 … 435.192

 BASE — LAST FIGURE PUBLISHED BEFORE THE LOCK 414.590 · 2026-05-01 

 TARGET PERIOD 2026-11-01 

 LOCKED AT — TIMESTAMP ASSIGNED BY THE DATABASE 2026-08-04T22:05:04.028874+00:00 

02 / WHEN THIS GETS ITS VERDICT

This forecast is graded against the FIRST figure the publisher releases for November 2026 — the number the market actually saw — and never against a later revision. That rule was fixed on 2026-08-03, before this forecast existed.

Headline grade (first_print): the earliest publisher vintage at or after the target period. Available roughly two months after the period ends, on the publisher's schedule, not ours.

Companion grade (settled_t_plus_12): the value as published twelve months after the target period, which measures how much the first figure was revised. Available roughly fourteen months after. Both definitions were committed before any grade existed under either.

INSUFFICIENT DATA

This forecast has not been graded. It cannot be: the period it names has not been published yet. When it is, the verdict appears here — pass or miss — and nothing on this page changes.

03 / PROVENANCE

 VINTAGE ID 7399c8f1-05c3-4cc6-bba8-193a98e76279 

 ARENA housing_us 

 SERIES MIDDLE_ATLANTIC 

 TARGET PERIOD 2026-11-01 

 LOCKED AT 2026-08-04T22:05:04.028874+00:00 

 MODEL ar12_logdiff 

 MODEL SPEC 1.1 

 MODEL SELECTION 425 observations >= 60 

 POINT STATISTIC median 

 FIT WINDOW 425 observations, 1991-01-01 → 2026-05-01 

 ARCHIVE AS OF 2026-08-04 

 COMMIT SHA 63e0fa12edfd75bea8ff26683a080669bd5c9473 

 RUN MANIFEST 9d992102-c049-4495-9a2f-1cfe4ca48d68 

PUBLISHER VINTAGES THIS FORECAST WAS BUILT FROM

Every input the reconstruction used, with the time the publisher released it. The forward-lock check reads these back from the record and fails the run if any of them postdates the lock above — that is what makes "locked before the outcome existed" a checked statement rather than a claim.

INPUT	PUBLISHER RELEASE TIME
observations:MIDDLE_ATLANTIC@2026-08-04	2026-08-04T00:00:00Z

CONTENT DIGEST

e94f894d2f0b2201a4879547d3e99e3c42dc460637222f7cd4e96bb3450d8c9c

SHA-256 over the payload serialized with object keys sorted lexicographically at every depth and no whitespace, computed when this page was built. It is not stored on the row, and it is not the commitment: the commitment is the append-only row and the lock timestamp the database assigned to it. Fetch the same payload from /v1/vintages and repeat this to check it.

04 / THE LOCKED PAYLOAD, VERBATIM

{
  "as_of": "2026-08-04",
  "model": "ar12_logdiff",
  "interval": {
    "label": "95%",
    "lower": 410.89735865042616,
    "upper": 435.1923003313906,
    "method": "ma_representation",
    "log_variance": 0.00021475415376124606
  },
  "base_value": 414.59,
  "commit_sha": "63e0fa12edfd75bea8ff26683a080669bd5c9473",
  "fit_window": {
    "last_period": "2026-05-01",
    "first_period": "1991-01-01",
    "observations": 425
  },
  "base_period": "2026-05-01",
  "forecast_value": 422.8703899673887,
  "horizon_months": 6,
  "forecast_inputs": [
    {
      "ref": "observations:MIDDLE_ATLANTIC@2026-08-04",
      "as_of": "2026-08-04T00:00:00Z"
    }
  ],
  "point_statistic": "median",
  "run_manifest_id": "9d992102-c049-4495-9a2f-1cfe4ca48d68",
  "model_spec_version": "1.1",
  "model_selection_reason": "425 observations >= 60"
}

GET /v1/vintages/7399c8f1-05c3-4cc6-bba8-193a98e76279

The One Lab · Toronto · Every number on this site resolves to a primary source or a graded model output. Where it can't, we say so. VINTAGE 7399c8f1 · WRITE-ONCE · NOT YET GRADED