Every CERES prediction is timestamped, publicly recorded, and graded against published IPC outcomes at T+90 days. This page is the permanent public record of what CERES predicted, when, and whether it was right.
Note: 0 predictions issued; the first T+90 grading windows opened June 2026. Observed IPC/FEWS NET classifications publish on a 2–4 month lag, so the earliest grades land Aug–Oct 2026. Grading is automated and pre-registered: the Brier decomposition computes the moment ≥10 outcomes are published, with no manual intervention.
The first T+90 grading windows opened June 2026. Grades are written automatically once IPC/FEWS NET publish the observed Current-Situation classification for each region, which lags the target window by 2–4 months. This ledger updates every Monday and nothing is graded against projected data.
Model initialised against 87 IPC transition records (2011–2023, 31 countries). 4 data-complete back-validation cases.
Grey = ideal calibration · Amber = CERES observed rate · (n) = predictions in bin
| IPC transition records | 87 country-seasons |
| Countries represented | 31 |
| Time period | 2011–2023 |
| Phase 4–5 events | 18 |
| Back-validation cases | 4 (data-complete only) |
| Perturbation draws | n=2,000 per prediction |
| Interval type | Input-perturbation 90% |
Table 1 from the CERES preprint. These metrics were pre-registered before any prospective outcome data was collected. No metrics will be selectively reported: all graded predictions remain permanently visible. Minimum sample sizes are fixed; targets cannot be revised retroactively.
| Metric | Definition | Min. N | Target date | Status |
|---|---|---|---|---|
| Brier Score | Mean (P̂₃ − O₃)² | 100 predictions | Jun 2026 | ⏳ Pending |
| Brier Skill Score | 1 − BS / BS_climatology | 100 predictions | Jun 2026 | ⏳ Pending |
| TIER-1 Precision | True TIER-1 / all TIER-1 issued | 30 TIER-1 alerts | Sep 2026 | ⏳ Pending |
| TIER-1 Recall | True TIER-1 / all Phase 4+ events | 10 Phase 4+ events | Sep 2026 | ⏳ Pending |
| Sensitivity interval coverage | Fraction outcomes in 90% interval | 200 predictions | Sep 2026 | ⏳ Pending |
| CRPS (ordered categorical) | Full distribution vs IPC phase | 500 predictions | Mar 2027 | ⏳ Pending |
| Reliability diagram | Forecast prob. vs empirical frequency | 500 predictions | Mar 2027 | ⏳ Pending |
Pre-registered in Pedersen (2026), Table 1. Protocol locked prior to accumulation of prospective outcome data.
Every prediction CERES issues is permanently recorded in this ledger with a timestamp, probability estimate, 90% sensitivity interval, and T+90 day grading date. We do not remove predictions that prove incorrect. We analyse and publish the reasons for forecast errors. The accuracy record here is the complete record: there is no curated subset. This is the foundation of institutional trust.