College Football Accountability
Every game's prediction is locked 90 minutes before kickoff — spread, total, win probability and vig-free moneylines, plus the market's opening and closing references — and never rewritten. After the final it is graded against the score. n is shown beside every figure and each model version is pooled separately, so eras never blend.
185 snapshots captured · 185 graded · 0 awaiting a final · model c3-v1.2, c3-v1.5, c3-v1.6.
n=185
bias -1.41
vs 0.2500 baseline
Spread bias -4.56 (+ = the projected home margin ran too high) · winner accuracy 86.0%.
By matchup type
Half an early-season college board is an FBS-vs-FCS game and its error
distribution is a different animal, so the two are never pooled into a single
headline. The FCS row is also where the fitted tier calibration
(fcs.spread_offset) has to keep proving itself in live grading.
| Subset | n | Spread MAE | Spread bias | Total MAE | Total bias | Brier |
|---|---|---|---|---|---|---|
| FBS vs FBS | 100 | 14.80 | -4.72 | 11.34 | -0.02 | 0.1571 |
| FBS vs FCS | 85 | 15.26 | -4.38 | 12.22 | -3.04 | 0.0517 |
| Neutral site | 4 | 7.28 | +6.88 | 22.14 | +4.54 | 0.2199 |
By week
| Week | n | Spread MAE | Spread bias | Total MAE | Total bias | Brier | Model |
|---|---|---|---|---|---|---|---|
| 0 | 8 | 16.71 | -2.35 | 12.01 | +6.11 | 0.2429 | c3-v1.2 |
| 1 | 91 | 15.66 | -5.85 | 12.48 | -0.93 | 0.0866 | c3-v1.5 |
| 2 | 86 | 14.17 | -3.41 | 10.94 | -2.62 | 0.1196 | c3-v1.6 |
By model version
More than one era is in this sample, so the pooled total above spans versions — these rows keep them apart.
| Version | n | Spread MAE | Total MAE | Brier |
|---|---|---|---|---|
| c3-v1.2 | 8 | 16.71 | 12.01 | 0.2429 |
| c3-v1.5 | 91 | 15.66 | 12.48 | 0.0866 |
| c3-v1.6 | 86 | 14.17 | 10.94 | 0.1196 |
Model vs closing line — paired sample, n=184
| Spread MAE | Total MAE | Brier | |
|---|---|---|---|
| Model | 14.93 | 11.66 | 0.1093 |
| Closing line | 12.39 | 11.30 | 0.1071 |
Head-to-head — spread: model 77, market 107, ties 0 · total: model 81, market 102, ties 1. Spread edge vs close: -2.55 points of MAE.
Closing-line value
spread: n=170 · moved toward the model 41% of the time · mean |open−close| 1.70 · mean |model−close| 7.70.
total: n=134 · moved toward the model 43% of the time · mean |open−close| 1.53 · mean |model−close| 4.35.
winprob: n=105 · moved toward the model 56% of the time · mean |open−close| 0.03 · mean |model−close| 0.13.
Cold-start games whose open and close resolve to the same odds row are excluded (0), never counted as zero movement.
Market references are recorded for comparison and CLV only — they are never blended into the model (SPEC-CFB §5). Moneylines are vig-free fair prices derived from the model's own win probability.