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.