The forecast scorecard
The part nobody else does: the locked forecast, scored in public and kept permanently — Brier, calibration, the named misses, and the seat-forecast error. More transparent than the raters, more accountable than the quants.
What will be scored
Two editions are locked and timestamped. When the certified 2026 outcomes arrive on the shared race spine, every call in each edition is scored automatically — and the original calls are preserved exactly as published.
Four things get scored: the Brier score on the win probabilities (overall and by office), the calibration curve (did our 70%-favorites win about 70% of the time?), the directional record with every miss named, and the seat-forecast error — was the actual composition inside our interval? The edition-1 → edition-2 comparison will show whether the revisions improved the call.
Proof the method works — the historical backtest
We can’t score 2026 yet, so here is the exact same scorecard run against cycles we already know the answer to. Each seat’s prior-cycle margin stands in for the call (the documented proxy), then it is scored against what actually happened. A stable cycle (2022) and a wave (2018) bracket what the real forecast will face.
Calibration
Did the favorites we put near a given probability win at that rate? On the line is perfectly calibrated.
The misses, named
Every call for the wrong party, most-confident first.
- MA Governorcalled R 96% · won D✗ miss
- AZ Senatecalled R 83% · won D✗ miss
- GA Senatecalled R 83% · won D✗ miss
- AZ Governorcalled R 83% · won D✗ miss
- MD Governorcalled R 83% · won D✗ miss
- NV Governorcalled D 71% · won R✗ miss
- PA Senatecalled R 58% · won D✗ miss
Seat-forecast error
Predicted versus actual chamber composition — and whether the result landed inside our interval.
Calibration
Did the favorites we put near a given probability win at that rate? On the line is perfectly calibrated.
The misses, named
Every call for the wrong party, most-confident first.
- NV Governorcalled R 96% · won D✗ miss
- FL Senatecalled D 83% · won R✗ miss
- MO Senatecalled D 83% · won R✗ miss
- NM Governorcalled R 83% · won D✗ miss
- IN Senatecalled D 71% · won R✗ miss
- ME Governorcalled R 71% · won D✗ miss
- MI Governorcalled R 71% · won D✗ miss
- NH Governorcalled D 71% · won R✗ miss
+7 more.
Seat-forecast error
Predicted versus actual chamber composition — and whether the result landed inside our interval.
How the calls are made — and how this is scored — is on the methodology page. The scoring data is openly licensed, like the rest of Akashic. · Back to the forecast →