The System · Week 8
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 |
|---|---|---|
| CAR at GB Thu 8:15 PM ET · locked | GB 66% featured this week | Green Bay Packers over the Panthers: Elo 64%, market 64%, System 66%. Tight agreement: go above both. |
| LV at NYJ Sun 1:00 PM ET · locked | NYJ 53% featured this week | New York Jets over the Raiders: Elo 50%, market 54%, System 53%. Coin flip: stay near 50. Smith is worth 22 Elo; Cousins is worth 70 Elo. |
| CLE at PIT Sun 1:00 PM ET · locked | PIT 67% featured this week | Pittsburgh Steelers over the Browns: Elo 64%, market 65%, System 67%. Tight agreement: go above both. Watson is worth 34 Elo. |
| IND at JAX Sun 1:00 PM ET · locked | JAX 79% featured this week | Jacksonville Jaguars over the Colts: Elo 78%, market 81%, System 79%. Tight agreement: go above both. JAX off a bye; wind 12 mph, 79°F (heat hurts favorites). |
| MIN at DET Sun 1:00 PM ET · locked | DET 55% featured this week | Detroit Lions over the Vikings: Elo 34%, market 62%, System 55%. Big disagreement: trust the market number. Murray is worth 100 Elo. |
| BAL at BUF Sun 1:00 PM ET · locked | BUF 65% featured this week | Buffalo Bills over the Ravens: Elo 75%, market 61%, System 65%. Big disagreement: trust the market number. BUF off a bye. |
| TEN at CIN Sun 1:00 PM ET · locked | CIN 88% featured this week | Cincinnati Bengals over the Titans: Elo 83%, market 88%, System 88%. Clear favorite, take the average. Burrow is worth 17 Elo; Ward is worth 19 Elo. |
| ARI at DAL Sun 1:00 PM ET · locked | DAL 74% featured this week | Dallas Cowboys over the Cardinals: Elo 70%, market 75%, System 74%. Clear favorite, take the average. Prescott is worth 17 Elo; Brissett is costing 40 Elo. |
| ATL at TB Sun 1:00 PM ET · locked | TB 54% featured this week | Tampa Bay Buccaneers over the Falcons: Elo 55%, market 54%, System 54%. Nothing to exploit; the blend is fine. Penix is worth 28 Elo; wind 6 mph, 79°F (heat hurts favorites). |
| LAC at LAR Sun 4:05 PM ET · locked | LAR 74% featured this week | Los Angeles Rams over the Chargers: Elo 71%, market 73%, System 74%. Tight agreement: go above both. Herbert is worth 18 Elo; LAC off a bye. |
| KC at DEN Sun 4:25 PM ET · locked | DEN 52% featured this week | Denver Broncos over the Chiefs: Elo 57%, market 50%, System 52%. Nothing to exploit; the blend is fine. Mahomes is worth 46 Elo. |
| NE at MIA Sun 4:25 PM ET · locked | NE 70% featured this week | New England Patriots over the Dolphins: Elo 63%, market 76%, System 70%. Big disagreement: trust the market number. Willis is worth 90 Elo; NE off a bye; wind 5 mph, 78°F (heat hurts favorites). |
| PHI at WSH Sun 8:20 PM ET · locked | WSH 70% featured this week | Washington Commanders over the Eagles: Elo 66%, market 69%, System 70%. Tight agreement: go above both. Hurts is worth 17 Elo; WSH off a bye. |
| CHI at SEA Mon 8:15 PM ET · locked | SEA 65% featured this week | Seattle Seahawks over the Bears: Elo 59%, market 62%, System 65%. Tight agreement: go above both. CHI off a bye; wind 2 mph, 46°F (cold helps favorites). |
If The System's numbers are right, it expects about 53.7 points this week.