Finding Correlated Parlays in Betting

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If you've wagered on sports for a while, you've probably heard the term correlated parlay used once or twice. Maybe not, however, as the concept is one that not many sports bettors pay close attention to. Many bettors have been warned away from parlays and stick to straight bets, which is probably the best way to go for the majority of bettors.

But correlated parlays are a different story, and there are times when making a parlay bet could prove to be beneficial in the long run.

What Is a Correlated Parlay?

A correlated parlay is essentially a bet that is tied into another, in that if one bet wins, it increases the odds of the other bet winning. As a rule, sportsbooks do not accept correlated wagers.

An example would be if you wanted to parlay a first half over bet to the game going over the total. Most, if not all, sportsbooks will not allow this type of wager because if you win your first half bet, the odds are greater that you will win your total wager for the game, as well.

A more blatant example would be parlaying the first half over to the second half over to the game over. If you win the first half over wager and the second half over bet, you're obviously going to win the wager for the game. Bookies who take these types of bets will not be in business for very long.

Finding Your Own Correlated Parlays

But there will be instances over the course of a season where bettors will stumble upon games and totals that essentially offer a correlated parlay opportunity. These will typically occur when you have two distinct styles of teams playing each other and one team is superior to the other.

Let's use the 2008 Alamo Bowl between Northwestern and Missouri as an example. The two conferences the teams play in couldn't be more different, which makes it difficult to predict the over/under. If you like Missouri, take the over, if you like Northwestern, you'll probably be wanting to see the under in since it's doubtful Northwestern can hang with Missouri in a shootout.

Essentially, what we're looking for are those cases where if Team A covers the point spread, it's more likely the game will go over or under the total.

When two teams with different styles meet, many times the oddsmakers set the total right in the middle. For example, say Duke is playing Princeton in college basketball and there are 160 points scored in Duke games and 100 scored in Princeton games. The middle point would be 130 points.

But since Duke is a far stronger team, the total will be somewhat tilted in that direction, so a total of 138 or so would be what you'd reasonably expect to see. If Duke was favored by 22 points, a bettor liking Duke would probably be inclined to believe the over would come through, while somebody taking Princeton would probably hope to see a low-scoring game, which would be more likely to help the Tigers stay within the large point spread.

If you liked Princeton in the game and were going to wager one unit on the Tigers, consider .90 of a unit on the Tigers and the remaining .10 units on a Princeton/under parlay.

If Duke blows out Princeton by 23 points or more, you're destined to lose your wager anyway. If the Tigers cover the point spread, you win your primary wager and wait to see how the total wager plays out.

The Logic Behind Looking for Correlated Parlays

Let's use a 10-game sample of $100 bets. If you make 10 straight $100 wagers and win six of them you'll have a profit of $160, which is derived by $600-$440=$160.

Now if you use the .90 - .10 rule described above, you would show a profit of $540-$396=$144 before factoring in the parlay wagers. (The $396 is derived from four losing bets at $99 each.)

The first thing we have to do is subtract $40 from our profit of $144 to account for the four losing parlays. This drops our profit to $104.

Out of our six remaining teams, which covered the point spread, we have six $10 parlays ongoing. If we win three of those six parlays, we'll lose an additional $30 and win an additional $72, which leaves us with a total profit of $148. This is less than the $160 profit we would have made by flat betting.

But if we win four of the six, we'll lose an additional $20, but show an additional profit of $104, giving us a total profit of $188, which is better than our flat-betting profit.

Since we are looking for those situations where if one team covers the point spread it greatly increases the likelihood of the game going over or under the total, a 66.7-percent ratio isn't as unattainable as it may sound at first. And all we have to do to show a larger profit or smaller loss is have our correlation be correct 55-percent of the time.

Using the same 10-game sample, say we were to go 5-5 instead. Flat betting would give us a $50 loss, while the .90-.10 ratio would give us a $45 loss before factoring in the parlays. Since we will automatically lose five of them for our five losing wagers, our loss now becomes $95.

Of the five winning bets, if we win two parlays, our total loss will become $73, which is worse than if we had stuck to flat betting. But if we win three of our five parlays, our total loss drops to $37, which is better than our flat rate loss of $50.

Using a 200-game sample, say we go 100-100. By flat betting, we'll have a $1,000 loss. Using the .90-.10 ratio, we'll show a $900 loss on our .90-unit bets and a $1,000 loss on our parlays, giving us a loss of $1,950.

Out of our 100 winning bets, we still have 100 $10 parlays going. If we were to win 54 of them, our total loss becomes $1,006 which is slightly more than what we would have lost by flat betting. But if we were to win 55 of them, our total loss would decrease to $970, which is less than we show by flat betting.

Wrapping Up

There is no magic formula that will let you know when a correlated situation arises. Instead, it's something that will come to sports bettors over time.

Correlated parlay situations don't often present themselves, but when they do, don't be afraid to put a little portion of your wager on a parlay, as well as on the team you like to cover the point spread.