Gambling on sports of all kinds has boomed in the past few years. The massive growth of Internet sportsbooks is responsible for part of this, but it's only recently that society as a whole (particularly in the Australian culture) has embraced it. Horse racing has historically been the sanctioned area in which to pit your predictive skills against the bookmakers, but the advice below is useful for any sport on which you can bet.
Before you start with a bookmaker, check out a few things:
You should choose a handful of bookies, because odds will vary from one to another. Why sacrifice a few percentage points you could have gained by shopping around? After all, you're working against their margin to begin with, and margin is everything.
Once you've decided on them, watch them like a hawk. The internet is good for this, as you can usually watch the odds unfold in real time.
Accept that you can't buy the field. The more individual bets you make on different competitors, the more times you pay the bookie's margin. I recommend the absolute extreme - only put serious money on your single best bet! Even taking a few of the favourites can make you a likely loser - you're then effectively giving the bookie terrific (and unjustified) odds on the rest of the field.
If the bookie is grouping your picks together under a single betting option, then that's OK. Just make sure that the margin per option is satisfactory.
Only joking. I don't have one. But you should be seeing by now that you have to be adept with figures to work out how good a proposition the bookie is really offering. Converting from odds to percentages and vice-versa should be natural for you. Only percentages add properly, and even then only if they're independent. Yeah, you need to study!
It's a quarter of the way through the NBA season, and you study the chart. San Antonio look an absolute lock to make the playoffs, but the bookie is still asking for bites! They have put up a quote of $1.04 (25 to 1 on, or -2500 for you Americans). Don't be silly. You'd be better off investing in a term deposit at your bank - 4% interest over 6 months, with the risk of losing the lot? I don't think so. In other words, if it's a "futures" bet, you need to look at it in comparison with the financial market, not just with your system.
What do you mean you don't have a system? Hey, can I be your bookie? If you're treating sports gambling like roulette, then sure, put your money on the table and have a spin. It can be proved that in the long term, in both cases, you are guaranteed to lose.
Get a realistic idea of how your system is performing, long-term, and if it's consistently below break-even, it's time to change. You can be sure that your bookmaker has a system, and it's a very complex one. This is their livelihood, after all.
This goes hand-in-hand with the previous point. Keep meticulous records. Are you really making money in the long-term, or is it just a gut feeling? Which sorts of bets are working for you? What proportion of your bad results (or your good results) do you think is due to chance? This can even be estimated scientifically. Because sport really is chance, almost as much as rolling a dice. It is genuinely possible for two teams to play who are equally likely to win (within a detectable margin).
The spread is just a way of keeping the available odds at about even-money, by giving one team a headstart which is statistically equivalent to their favouritism. There is nothing better or worse about the spread than head-to-head betting - unless of course your modelling system says so!
A parlay, for those not familiar with it, lets your winnings ride onto other events. It's sometimes called a combination bet. The bookie gets a margin out of every combination, but following my earlier advice you're only betting on one anyway. In each case, get out a calculator and work out whether the parlay represents value for money. Compare it with the separate events. Factor in the dependency (if any).
You'll usually find that there is not much gain in it either way, but a parlay can be a good way of combining your system's picks for a lot of gain. Bear in mind that even four 75% chances combine to make an overall 32%. A loss here is not a sure indication that you're wrong, just that the dice fell the wrong way for you, as they usually will given enough chances!
This one's easy. It is never a particularly wise move to bet on a doubly-constrained result. I'd almost call them sucker bets. For instance, consider the "tri-bet" of Australian rules. You can bet on team A by over 15.5 points, team B by over 15.5 points, or a result of under 15.5 points. The squeeze play (the one in the middle), is usually set at about $2.80, which your average mug punter might see as juicy between two evenly-matched teams.
It isn't. The bookie's mathematical models, and in fact everyone else's if they have any wits at all, show that about 32% of matches between two equal teams will be decided by less than 15.5 points. Mathematical models are very robust when it comes to these sorts of figures. You cannot beat statistics in the long run. The bookies add their margin, and suddenly you're asked to take $2.80 (about 36% chance). Sure, it might rain and keep the scores down, but be assured that the bookmaker has factored this in. Unless you've fixed the game yourself, don't take this bet!
Similarly, don't take anything but a whitewash in tennis sets betting, and never bet on the draw in soccer. Long term, you can't win. If your system says that the squeeze play is a marginally good bet, it's sure to be saying that one of the fringes is even better. If you don't like the small chance of a payout on the fringe, then stick to head-to-head and spread.
Copyright © Darren O'Shaughnessy 1999. This document may not be reproduced without the written permission of the author.
Recommended: The Betting Ring is a great Australian site for checking out bookmakers and their odds.
darren@rankingsoftware.com