The System · Week 3
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 |
|---|---|---|
| ATL at GB Thu 8:15 PM ET · locked | GB 70% featured this week | Green Bay Packers over the Falcons: Elo 66%, market 69%, System 70%. Tight agreement: go above both. Penix is worth 28 Elo. |
| NYJ at DET Sun 1:00 PM ET · locked | DET 72% featured this week | Detroit Lions over the Jets: Elo 69%, market 73%, System 72%. Clear favorite, take the average. Smith is worth 22 Elo; DET off a bye. |
| HOU at IND Sun 1:00 PM ET · locked | HOU 53% featured this week | Houston Texans over the Colts: Elo 52%, market 53%, System 53%. Coin flip: stay near 50. |
| KC at MIA Sun 1:00 PM ET · locked | KC 73% featured this week | Kansas City Chiefs over the Dolphins: Elo 52%, market 84%, System 73%. Big disagreement: trust the market number. Willis is worth 90 Elo; Mahomes is worth 46 Elo; wind 4 mph, 83°F (heat hurts favorites). |
| TEN at NYG Sun 1:00 PM ET · locked | NYG 57% featured this week | New York Giants over the Titans: Elo 59%, market 56%, System 57%. Tight agreement: go above both. Winston is costing 71 Elo; Ward is worth 19 Elo; wind 16 mph (matters), 61°F. |
| CIN at PIT Sun 1:00 PM ET · locked | CIN 58% featured this week | Cincinnati Bengals over the Steelers: Elo 50%, market 61%, System 58%. Big disagreement: trust the market number. Burrow is worth 17 Elo. |
| SEA at WSH Sun 1:00 PM ET · locked | SEA 76% featured this week | Seattle Seahawks over the Commanders: Elo 71%, market 77%, System 76%. Clear favorite, take the average. Lock is costing 30 Elo. |
| NE at JAX Sun 1:00 PM ET · locked | JAX 57% featured this week | Jacksonville Jaguars over the Patriots: Elo 53%, market 59%, System 57%. Nothing to exploit; the blend is fine. wind 8 mph, 84°F (heat hurts favorites). |
| LAC at BUF Sun 1:00 PM ET · locked | BUF 78% featured this week | Buffalo Bills over the Chargers: Elo 77%, market 75%, System 78%. Tight agreement: go above both. Herbert is worth 18 Elo; BUF off a bye. |
| CAR at CLE Sun 1:00 PM ET · locked | CAR 52% featured this week | Carolina Panthers over the Browns: Elo 44%, market 54%, System 52%. Big disagreement: trust the market number. Watson is worth 34 Elo. |
| ARI at SF Sun 4:05 PM ET · locked | SF 81% featured this week | San Francisco 49ers over the Cardinals: Elo 78%, market 77%, System 81%. Tight agreement: go above both. Brissett is costing 40 Elo. |
| MIN at TB Sun 4:05 PM ET · locked | MIN 56% featured this week | Minnesota Vikings over the Buccaneers: Elo 74%, market 51%, System 56%. Big disagreement: trust the market number. Murray is worth 100 Elo; wind 7 mph, 84°F (heat hurts favorites). |
| LV at NO Sun 4:25 PM ET · locked | NO 61% featured this week | New Orleans Saints over the Raiders: Elo 52%, market 64%, System 61%. Big disagreement: trust the market number. Shough is costing 16 Elo; Cousins is worth 70 Elo. |
| BAL at DAL Sun 4:25 PM ET · locked | BAL 61% featured this week | Baltimore Ravens over the Cowboys: Elo 57%, market 62%, System 61%. Nothing to exploit; the blend is fine. Prescott is worth 17 Elo. |
| LAR at DEN Sun 8:20 PM ET · locked | DEN 51% featured this week | Denver Broncos over the Rams: Elo 57%, market 49%, System 51%. Nothing to exploit; the blend is fine. wind 10 mph, 78°F (heat hurts favorites). |
| PHI at CHI Mon 8:15 PM ET · locked | PHI 65% featured this week | Philadelphia Eagles over the Bears: Elo 61%, market 64%, System 65%. Tight agreement: go above both. Keenum is costing 100 Elo; Hurts is worth 17 Elo. |
If The System's numbers are right, it expects about 45.1 points this week.