The general rule regarding parlays is: DON'T.
Parlays generally carry a higher house edge than straight bets, therefore you give the book a more impressive advantage over you when you play them. That, alone, is reason enough to suppress the misplaced feelings of greed coupled with fear that often result in betting parlays. People think they're risking less with parlays, but they aren't. They believe they are able to win more with parlays, however they cannot. The higher win with parlays is far outweighed by the higher probability of losing. Parlay bettors are actually risking more, with less probability of collecting.
A parlay is not an individual bet. It really is two bets -- a one-unit bet on one team and a two-unit bet on the other. Which team gets the two-unit bet? In point-spread betting at constant money odds, if both teams win or both teams lose it doesn't matter which team gets the double bet. When one team wins and one team loses, however, the double bet is presumed to possess been on the loser. How smart is that for the bettor? Just do it, make a parlay. We'll wait until both games are over, and in case of a split we'll put the double bet on the loser. If your bookmaker sold you a parlay with that line, how many of you would still make the bet?
A parlay is also bad money management. In a parlay you either bet double on the next team, or nothing on that same team, depending upon whether the first game won or lost. That adds an element of luck to your betting that doesn't should be there. The skilled handicapper is definitely seeking to make smart investments. He tries to remove the effect of luck to the best extent possible in order to make his results as predictable as possible.
As with every rule, however, there are exceptions. The exception to the rule regarding parlays occurs when the two bets are co-dependent.
I knew one bookmaker who was taken for tens of thousands because he didn't understand the co-dependency of certain bets. He allowed a new player to consistently parlay the first half with the overall game. The ball player parlayed totals by combining the over in the first half with the over in the game, and the under in the first half with under in the overall game. Both parlays were manufactured in the same game. Every time the player won he'd win 2.6 times his bet. Betting $100 on each parlay, if one of these won, the player would win $260 and lose $100 on the other parlay for a net win of $160. He could never win both parlays. If he lost both parlays he'd lose $200.
At first glance, this were a great chance for the book. The normal coin-flip odds of winning one parlay out of your two are 50-50. As far as the bookie was concerned the bettor ought to be winning $160 half enough time, and losing $200 half the time. The bettor, however, making $500 parlays, was ahead more than $20,000 after six months, and the book began to look at what the bettor was doing more carefully.
The problem for the bookmaker was that both halves of each parlay were co-dependent. At the end of the first half, the bettor was hardly ever in a 50-50 situation.
Take the Thursday night game between Utah and Air Force. The game total was 53 and the initial half total was 27. By the end of the initial half, the score was 31-21, for a complete of 52 first-half points. The initial half of one of many parlays, the "over" in the initial half was successful. For the parlay probability to be correct, there should now be considered a 50-50 possibility of winning the "over" for the overall game. Obviously the odds of winning the "over" in the game weren't 50-50 but much better than 99% in favor of the "over." The ball player only needed to win the first 1 / 2 of the parlay to be virtually assured that he would collect 2.6 times his money rather than just $10 for $11.
Before you rush out to try this, remember that most off-shore books are far too smart to let you parlay first half to game. Should they do allow you to do this, start worrying about collecting because that book will be taken up to the cleaners.
You can find, however, some less obvious co-dependent parlays that can be made at many books. One type of co-dependent parlay is the parlay of the medial side and total in exactly the same game.
Any game where the total is significantly less than double the spread can give you an edge in parlaying side to total in the same game. We've already discussed, in a prior article, how to use these anomalous side and total combinations to hedge one another and increase your win with hardly any increase in risk. Such a bet, however, required that you have an opinion privately or the full total. Parlaying is another method to increase your potential win on these games, or even to develop a potential win when you have no opinion.
There are two games this Saturday that qualify. They are Virigina -25 over Duke with a total of 48 �, and Kansas St. -24 � vs. North Texas with a total 46 �).
In the Virginia game, if you believe that Virginia covers the 25 points, they must hold Duke to no more than 11 points or the game will go over the full total. The much more likely it becomes during the game that Virginia covers 25 points, the more likely it becomes that the overall game will go over 48 �. The wider Virginia's winning margin, the much more likely the game will review. If you like Virginia to cover the spread, and you believe that Duke will never be shut out, in that case your probability of winning a parlay on Virginia and the over are higher than the standard 25%. Likewise, if the scoring stays low, it really is less likely that Virginia covers the 25 points. As a result, the probability a parlay of the under with the underdog will win is higher than the normal 25%.
In case you have no opinion on the overall game, you can parlay the favourite with the "over" and the underdog with the "under" and collect sufficiently often to exceed the losses when both parlays lose. In the only other game meeting the qualifications this week -- Friday's game between California -30 against New Mexico State with a total of 58 -- the under has recently won with the underdog for a winning two-parlay spread.
The closer the posted total is to the spread on the side, the better win-rate will undoubtedly be on the parlay "spread" bet. Hi88 -dependency in side to total parlays isn't as strong as parlaying first half and game totals (if it were, most books would not allow such bets), but there is a sufficient co-dependency in the games with low totals and high spreads to help make the strategy profitable long-term.
Not all bookmakers will allow you to parlay the side to the full total in exactly the same game, because progressively more are realizing these bets are occasionally co-dependent. But, enough books still do allow such bets for you to consider including such bets in your professional betting arsenal.
If your bookmaker provides "if/reverse" bets, it is possible to replace the parlay bet with an "if/reverse" bet and achieve greater success.