Over/Unders can be very tricky for casual bettors, who tend to bet with their gut instead of thinking through the process. Worse, they fall prey to the temptation to treat totals like roulette. If they see a team is playing some Overs, some will think that means you should ride the Over streak, while others think Under is due, so you’ve got to bet Under.
Playing that way doesn’t beat roulette. You can’t beat roulette without cheating because the payouts don’t reflect true odds, and the 0 and 00 create a high virtual vigorish that can’t be overcome. The approach won’t beat the 11/10 vigorish in sports betting, either, particularly since the market tends to react quickly to publicly obvious tendencies.
The key factors for finding vulnerable totals to bet are:
Evaluating the scoring skill sets of the offenses.
Evaluating the point-denial skill sets of the defenses.
Evaluating the pace of the offenses.
Evaluating the ability (or inability) of the offenses to run clock with a lead.
Evaluating game conditions that will influence scoring, such as weather and field surface.
Evaluating the market’s assessment of the game.
You can do a ton of work determining that the Over/Under should be 52, only to find out the betting market is way ahead of you and already has the game in the 51-53 range.
Generally, the public devotes most of its efforts to studying offenses. Bettors want to bet Overs because it’s more fun to root for points than to bet Under and sweat every play wondering if you’re about to get burned with a long touchdown. If at least one team has a great offense, the public wants to bet the Over.
Not enough attention is paid to:
Defenses, particularly the ability of some defenses to force field goal attempts rather than allow touchdowns. Worse, if a game looks like it will be a defensive struggle, the public will just pass rather than bet the Under.
Pace or tempo, meaning the number of offensive plays each team is likely to run. This is more important than ever in college football because so many teams are running fast-break spread attacks. To the degree it is considered, it encourages the love of Overs for too many casual bettors while ignoring Under potential in slower-paced games.
Running out the clock with a lead, which is part of how New England Patriots games went 6-10 to the Under last season even with a Hall of Fame quarterback leading a sharp offense to a 14-2 record. Offenses, particularly in the NFL, have become very savvy about getting a game over with when they have a big lead. This constantly provides great frustration for Over bettors.
Weather, particularly wind. You’ve probably realized that Over/Unders often drop 2-3 points when there’s a strong chance of rain. Studies have shown that precipitation decreases scoring over the long haul. It’s not a 100% rule of thumb. More like a 55/45 rule, maybe 58/42. The problem is that too many people, particularly former coaches and players who are now sportscasters, remember the games when teams scored anyway thanks to cheap points and fluke plays — and then try to tell you that rain helps scoring. Occasionally it does. More often it doesn’t. That’s why, for years, sharps have always pounded Unders when rain was forecast and why oddsmakers will now move quickly to reduce totals in wet-weather scenarios. Quants and other sharps don’t bet by anecdote. They study decades of results. Over/Unders drop on news of rain because of what was learned in those decades of study.
Wind? Only recently has the market started paying more attention to this. You can make the case that it still hasn’t adjusted all the way. Some sharps will bet Unders hoping for 55/45 success whenever the forecast is for sustained winds of at least 10-15 mph, and particularly at forecasts for high gusts. Again, nothing is right all the time. But any stadium with swirling or gusty winds will wreak havoc on the passing game and field goal attempts.
If you want to add Over/Unders to your arsenal, either to increase your entertainment on recreational bets or for investment purposes, it’s a good idea to mentally play the game in your head to visualize how each team’s skill sets are likely to interact in that day’s environment. Quants, of course, have models that can do this thousands of times. The same principles of logic apply either way.
You want to bet Overs when:
— The market hasn’t fully appreciated the scoring potential for these offenses …
— Against these defenses …
— Adjusted for likely pace …
— Ideally in great scoring conditions …
— But accounting for the potential liability of the fourth-quarter leader likely running out the clock with a scoreboard advantage.
You want to bet Unders when:
— The market hasn’t fully appreciated the scoring challenges for these offenses …
— Against these defenses …
— Adjusted for pace …
— Accounting for the ability of the leader to run out the clock …
— Ideally in game conditions that will hinder offenses even more.
You don’t want to bet Over just because your initial gut reaction is that the game will be a shootout. The total in the NFL is probably at least 52-55 in that case, maybe 65-70-plus in the colleges. Most fans have the same gut reactions when high-scoring teams play each other. Not much value there.
You also don’t want to have the mindset that NFL rules changes have made it so easy for quarterbacks that you can’t even bet Unders. The market knows about the rules changes. Besides, it’s possible to help a quarterback in a way that generates Unders if it’s helping him run clock with short passes that move the chains in the fourth quarter.
Probably most importantly, respect the market instead of assuming that Over/Unders are soft. You can find winners. But by the time you’re betting, opening lines from experienced oddsmakers have been shaped by the sharpest influences in the market. Work hard to find a handful of edges, particularly in games in which public misperceptions are having an undue influence on game-day prices.