Before crunching the Predict-O-Nomics on another slate of SEC games, new TWER contributor Mac Mirable shares some tricks of the trade that should have numbers geeks — and gambling addicts — foaming at the mouse.
For those of us constantly obsessing over how well Auburn would stack up against the rest of the SEC, I’ve created this handy table – the Vegas Lines matrix. For more information on what the Vegas Lines Matrix is, how it works, and why you should care, check out last week’s column. (As always, click to enlarge.)
Changes this week
Based on how all teams played last week, I — acting on behalf of Vegas bookies — have adjusted the matchup lines you could expect if these teams played this week. A few things to mention first…
In order to “improve” a team’s odds, one of three things needs to occur: 1) the team needed to improve on their per-game statistics in the past week, or 2) their opponent’s per-game statistics needs to get worse, 3) the team needs to move up in the polls. When a team like Alabama embarrasses Florida, but doesn’t put up big offensive numbers and can’t move up in the polls from #1, the Vegas odds model will ding them, ever so slightly. When a team like Auburn improves in many statistical categories and moves up the polls, the Vegas odds model will reward them. So good news for Auburn: almost all lines moved in favor of the Tigers. In our remaining games, we see the following changes:
Auburn at Kentucky: Line moved from Auburn being an 11-point favorite entering Week 5 to a 13-point favorite entering Week 6. (Actual line: +8)
Arkansas at Auburn: Slight move from Auburn being a 5-point favorite to a 5.5 point favorite.
LSU at Auburn: Line moved from Auburn being a 2-point favorite to a 4.5-point favorite.
Auburn at Ole Miss: No change, Auburn remains a 7.5-point favorite
Chattanooga @ Auburn: This game is off the board. Auburn would likely be a 45-point favorite.
Georgia @ Auburn: Line moves from Auburn being a 16.5 point favorite to a 19-point favorite.
Auburn @ Alabama: Line moves from Auburn being a 16-point underdog to a 14-point underdog.
How the Vegas Lines Matrix compares to the actual Vegas lines
My predictions are relatively close to what Vegas is currently saying, the biggest difference being a 5-point difference in the Auburn vs. Kentucky game. Out of conference games do not currently have any predictions in the Vegas Lines matrix.
We can use these odds to get the implied probability of winning in these matchups. These probabilities are calculated using thousands of prior games. For example, let’s consider the actual Auburn at Kentucky spread, where Kentucky is an 8-point home underdog. In the past 10 years (the period my data covers) there have been 56 games where the home team was an underdog by exactly 8 points. In these 56 games, the home team won 11, and lost 45, for an implied win probability of 28%. If the line moves “down” to +7 points, we have a little more data: 149 games, 44 wins for a win percentage of 31%.
By populating the above matchup matrix with these probabilities, we can”simulate” the remainder of the season, and calculate such things as a team’s expected record or probability of going undefeated.
The table above reveals that Vegas likely thinks no one has a great shot at beating Alabama at home this year. Florida had an 18% chance of doing it last week and failed miserably. Auburn has an 18% chance of doing it in the Iron Bowl, up from a 14% chance last week. If Alabama is going to lose, it’s going to have to come on the road. This week against South Carolina, they have a 33% chance of losing. Of Alabama’s remaining 7 games, we’d forecast they should win 5.7 of them on average (with their being some small chance of their losing any of them – which adds up to their losing a total of one game). At this point in the season, they have a 20.9% chance of winning out and going undefeated.
Auburn’s future looks about the same as it did last week. October is going to be a difficult month for Auburn to make it through unscathed. Odds are, Auburn will be 3-1 in the remaining games this month; there’s only a 25% chance that the Tigers will make it through unbeaten. Auburn has a 3.9% chance of winning out and going undefeated prior to the SEC title game.
Predicted Final Standings
Things aren’t very likely to shake out exactly like this, but it’s a start. Alabama faces Florida in Atlanta. Auburn again goes to a New Year’s Day bowl.
Mac Mirabile is a 2002 graduate of Auburn’s economics and journalism departments. During his time at Auburn, he was a copy and photo editor with The Auburn Plainsman. He has a master’s in economics from UNC-Chapel Hill and has written numerous academic publications on college football, the NFL and gambling markets. His previous columns can be found here. Email him at firstname.lastname@example.org.