The System · Week 7
Ten rules, each with the number that earned it. Tested on 27 seasons, 1999–2025, 6,918 decided games: the 24 FiveThirtyEight published and every season Delta Sunday has replayed itself, refreshed as each week finishes. Per season over the 27: The System 1,011 points, the blend 1,003, the market alone 997, Elo 892. Against Elo that is 119 a season with a standard error of 19, ahead in 24 of 27 seasons: a real gap. Against the market it is 14 a season with a standard error of 10, ahead in 16 of 27: even, within the noise. And the rules were chosen on these same seasons, so treat the edge over the market as flattering; the seasons the site replayed itself went −16, +90 and +32.
- Start from the market. Over 27 seasons (1999–2025) the closing line scored 997 points a season; Elo scored 892.
- Add Elo at a quarter weight. A hair better than the market alone and it explains itself: quarterback changes, rest, the reasoning on every card. Half weight costs 17 a season.
- Nudge tight agreement by 2. Same favorite of 55% or more, within 4 points. Favorites there won 69.8% against a 67.6% forecast over 2,607 games. Small, but consistent across eras.
- Don't chase Elo's disagreements. Ten or more points apart, Elo's side won 50% while Elo claimed 65% and the market 48%, over 1,102 games. The quarter weight already handles it.
- Don't cap your confidence. Every cap tested cost points, in the long run and in the recent replays.
- Play coin flips at the number, not 50. Forcing 50 cost points.
- Playoffs: same blend. Elo and the market are level in January over 248 games. A heavier Elo weighting looked good on 39 recent games and did not hold.
- The lock gets the same 2-point nudge, no more. Locks won 85% (434-76) against a 79% forecast over 27 seasons. Pressing them by 5 cost points over 510 locks.
- Never skip a game. A skip is a 50/50 pick worth zero. Every System number expects positive points.
- Mind the weather, outdoors. Wind of 15 mph or more: favorites won 62% against a 65% forecast, so shrink toward 50 by a fifth. Fifty degrees or colder: favorites won 69% against 66%, so add 2. Over 75: shrink by a tenth. Together about 9 points a season over 24, positive in every era. Domes get nothing.
Every rule we tried beyond these cost points. The discipline is to play the numbers, and move one only when you know something the models don't: a late scratch, weather, a benching. The System is scored on every leaderboard next to the plain blend, so you can see whether the last two rules earn their keep this season.
| Game | The System | Why |
|---|---|---|
| NE at CHI Thu 8:15 PM ET · locked | CHI 58% featured this week | Chicago Bears over the Patriots: Elo 54%, market 59%, System 58%. Nothing to exploit; the blend is fine. |
| PIT at NO Sun 9:30 AM ET · locked | PIT 62% featured this week | Pittsburgh Steelers over the Saints: Elo 63%, market 60%, System 62%. Tight agreement: go above both. Shough is costing 16 Elo. |
| CIN at BAL Sun 1:00 PM ET · locked | CIN 57% featured this week | Cincinnati Bengals over the Ravens: Elo 48%, market 60%, System 57%. Big disagreement: trust the market number. Huntley is costing 16 Elo; Burrow is worth 17 Elo; CIN off a bye. |
| NYG at HOU Sun 1:00 PM ET · locked | HOU 81% featured this week | Houston Texans over the Giants: Elo 76%, market 80%, System 81%. Clear favorite, take the average. McCarthy is costing 88 Elo. |
| SF at ATL Sun 1:00 PM ET · locked | SF 60% featured this week | San Francisco 49ers over the Falcons: Elo 67%, market 58%, System 60%. Nothing to exploit; the blend is fine. Penix is worth 28 Elo. |
| TB at CAR Sun 1:00 PM ET · locked | CAR 61% featured this week | Carolina Panthers over the Buccaneers: Elo 65%, market 60%, System 61%. Nothing to exploit; the blend is fine. |
| CLE at TEN Sun 1:00 PM ET · locked | CLE 56% featured this week | Cleveland Browns over the Titans: Elo 62%, market 55%, System 56%. Nothing to exploit; the blend is fine. Ward is worth 19 Elo; Watson is worth 34 Elo. |
| IND at MIN Sun 1:00 PM ET · locked | MIN 77% featured this week | Minnesota Vikings over the Colts: Elo 87%, market 74%, System 77%. Big disagreement: trust the market number. Murray is worth 100 Elo; MIN off a bye. |
| MIA at NYJ Sun 1:00 PM ET · locked | NYJ 61% featured this week | New York Jets over the Dolphins: Elo 50%, market 65%, System 61%. Big disagreement: trust the market number. Smith is worth 22 Elo; Willis is worth 90 Elo; MIA off a bye. |
| DEN at ARI Sun 4:05 PM ET · locked | DEN 69% featured this week | Denver Broncos over the Cardinals: Elo 73%, market 67%, System 69%. Clear favorite, take the average. Brissett is costing 40 Elo; DEN off a bye. |
| LAR at LV Sun 4:25 PM ET · locked | LAR 58% featured this week | Los Angeles Rams over the Raiders: Elo 48%, market 61%, System 58%. Big disagreement: trust the market number. Cousins is worth 70 Elo. |
| GB at DET Sun 4:25 PM ET · locked | DET 66% featured this week | Detroit Lions over the Packers: Elo 61%, market 65%, System 66%. Tight agreement: go above both. DET off a bye. |
| KC at SEA Sun 8:20 PM ET · locked | SEA 61% featured this week | Seattle Seahawks over the Chiefs: Elo 60%, market 58%, System 61%. Tight agreement: go above both. Mahomes is worth 46 Elo; SEA off a bye. |
| DAL at PHI Mon 8:15 PM ET · locked | DAL 61% featured this week | Dallas Cowboys over the Eagles: Elo 45%, market 66%, System 61%. Big disagreement: trust the market number. Hurts is worth 17 Elo; Prescott is worth 17 Elo. |
If The System's numbers are right, it expects about 32.6 points this week.