Zoltar is my NFL football prediction computer program. It uses a neural network and a type of reinforcement learning. Here are Zoltar’s predictions for week #5 of the 2023 season. These predictions are fuzzy, in the sense that it usually takes Zoltar a few weeks to hit his stride.

Zoltar:  commanders  by   10  dog =       bears    Vegas:  commanders  by  6.5
Zoltar:       bills  by    6  dog =     jaguars    Vegas:       bills  by  5.5
Zoltar:     falcons  by    6  dog =      texans    Vegas:     falcons  by  4.5
Zoltar:      titans  by    0  dog =       colts    Vegas:      titans  by  0.5
Zoltar:       lions  by    8  dog =    panthers    Vegas:       lions  by    9
Zoltar:    dolphins  by    6  dog =      giants    Vegas:    dolphins  by   11
Zoltar:    patriots  by    4  dog =      saints    Vegas:    patriots  by    1
Zoltar:      ravens  by    0  dog =    steelers    Vegas:      ravens  by  4.5
Zoltar:     bengals  by    3  dog =   cardinals    Vegas:     bengals  by    3
Zoltar:      eagles  by    5  dog =        rams    Vegas:      eagles  by    4
Zoltar:        jets  by    0  dog =     broncos    Vegas:     broncos  by    1
Zoltar:      chiefs  by    0  dog =     vikings    Vegas:      chiefs  by    5
Zoltar: fortyniners  by    6  dog =     cowboys    Vegas: fortyniners  by  3.5
Zoltar:     packers  by    0  dog =     raiders    Vegas:     packers  by    2 

Zoltar theoretically suggests betting when the Vegas line is “significantly” different from Zoltar’s prediction. In mid-season I typically use 3.0 points difference but for the first few weeks of the season I am usually a bit more conservative and use 4.0 points difference as the advice threshold criterion.

At the beginning of the season, because of Zoltar’s initialization (all teams regress to an average power rating) and other algorithms, Zoltar is very strongly biased towards Vegas underdogs. I probably need to look at this.

For week #5, using a conservative 4.0 point difference between Zoltar’s predictions and the Vegas point spread, Zoltar has three suggestions:

giants       at     dolphins : bet underdog giants
ravens       at     steelers : bet underdog steelers
chiefs       at      vikings : bet underdog vikings

Using a more aggressive 3.0 point difference:

bears        at   commanders : bet favorite commanders
giants       at     dolphins : bet underdog giants
ravens       at     steelers : bet underdog steelers
chiefs       at      vikings : bet underdog vikings

For example, a bet on the underdog Steelers against the Ravens will pay off if the Steelers win by any score, or if the favored Ravens win but by less than 4.5 points (in other words, by 4 points or less).

Theoretically, if you must bet $110 to win $100 (typical in Vegas) then you’ll make money if you predict at 53% accuracy or better. But realistically, you need to predict at 60% accuracy or better.

In week #4, against the Vegas point spread, Zoltar went 2-0 (using 4.0 points as the advice threshold). Zoltar correctly predicted the Buffalo Bills would cover the spread against the then-undefeated Miami Dolphins, and Zoltar correctly predicted the underdog Jets would keep their game close against the Kansas City Chiefs.

For the season, against the spread, Zoltar is 18-12 (60% accuracy).

Just for fun, I track how well Zoltar does when just trying to predict just which team will win a game. This isn’t useful except for parlay betting. In week #4, just predicting the winning team, Zoltar went 12-4 which is good but not great. Vegas was a bit worse, going 10-6 at just predicting the winning team,

My system is named after the Zoltar fortune teller machine you can find in arcades. Zoltar uses a crystal ball. There are lots of movies that feature crystal ball fortune tellers. Left: In “The Wizard of Oz” (1939), the wicked witch is using her crystal ball to spy on Dorothy and companions. Center: In “Labyrinth” (1986), Jareth the Goblin King offers to show Sarah her forgotten dreams. Right: In “Harry Potter and the Prisoner of Azkaban” (2004), wacky Sybil Trelawney is a not-so-competent Professor of Divination.