Overs/Unders are all about how offenses match-up with defenses - period. That's why a team can score 35 points one week and 13 points the next. If you look at just the points they've scored against other teams and not against the team they're facing, you're going to be stuck with a lot of headaches.
I have what I call a RipRating, which makes an attempt to put offensive and defensive rankings into perspective and helps me decide whether to play the over or under. I'll give you an example for this Mia v. NYG game.
Rushing offense rankings are based on rushing yards per game. I don't use yards per carry because of teams like Oakland: They average 6 yards/carry but don't run the ball and their avg yards per game is only 80+. Which is a more accurate portrayal of their rushing O? Per/game.
Rushing defense, conversely, is based on yards allowed/game.
Passing offense is based on team QB rating. We judge the overall performance of a QB, statistically, with this stat and it only makes sense to use it when statistacally ranking passing offenses.
Passing defense, conversely, is Opponents QB Rating against.
OK, let's get started.
Rushing Offense:
Mia 6
NYG 14
Rushing Defense:
Mia 2
NYG 9
Passing Offense:
Mia 13
NYG 15
Passing Defense:
Mia 10
NYG 17
Rip Ratings = Offensive ranking compared to oppents defensive ranking. Team X's Offensive Ranking = 1. Team Y's Defensive Ranking = 13. X's offense, compared to the rest of the league, is 12x's better than Team Y's defense. Their RipRating = +12.
So Miami's Rush O is ranked 6 while NYG Rush D is ranked 9. Offensive has the advantage here as 6 is lower (better) than 9 by a difference of 3 ranking points. This gives Miami a Rush RipRating of +3
Rushing:
Mia +3
NYG -12
Passing:
Mia +4
NYG -5
Analysis:
None of those ratings are very high. This week, some ratings are +27, +21, +14, +18, etc. +4 and +3 are low comparatively. This suggests that the defenses match up pretty well. The lower the number, the greater the advantage the defense has. This game is weighed in favor of defense, which supports a lower scoring game.
Generally (unless you have Jamal Lewis running against the Browns), passing is going to lead to more scoring than running will. It stops the clock more frequently, provides yardage in chunks and usually leads to more turnovers, which in turn, lead to points. Likewise, if both teams are better defensively against the pass, it's going to lead to less scoring because both teams will need to run the ball more and that will keep the clock working. Passing is the key here, in my mind, in determining over/under. It has a greater effect on the total score.
So...
I add together both teams Pass RipRatings and multiply them by 2. I then add this number to both Rush RipRatings and the number I get is the one I use to determine over/under.
So...
Rushing:
Mia +3
NYG -12
Passing:
Mia +4
NYG -5
Analysis:
Passing added to gether: +4 added to -5 = -1.
Passing multiplied by 2: -1 x's 2 = -2.
That number is then added to the offensive scores: -2 +3 -12 = -11.
The over/under RipRating for this game = -11. I use negative numbers as a predictor for unders and positive numbers as a predictor for overs.
To put this in perspective, we'll use last weeks games...
There were seven games that produced Over/Under RipRatings of less than zero, or negative, which suggests under.
Of those games, 6 of them went under.
Now, the lower the number, the higher confidence I have in betting the under. This game, with a rating of -11, isn't very low. This suggests to me it's going to be under, but probably not by much. I assume the oddsmakers know what they are talking about with over/unders, so I set my zero to their number.
I wouldn't bet the under based solely on this, everything else needs to be taken into consideration, I just use it as a tool to get me started in a direction.
It's a fairly new way of looking at things for me, but it was highly successful last. I wouldn't be so quick to jump on the over in this game. Definitely read up as much as you can.
Also, this game is pretty unique as both teams are coming off a bye week. It's hard to predict those types of games. They usually push me away from them because if I can limit the x-factors, I think I give myself a little better shot.
Good luck this week and if you have any questions, let me know. It was kind of a long explanation, but it's working so far.
Good luck!
