[Guide] Math for sport betting

What we will go through in this article:

  1. The house always wins?
  2. Understanding the vig
  3. Choosing the best betting site
  4. Applying Mathematics to Bonus Offers
  5. Choosing the Right Bets

Many punters and potential punters, even some who have been betting for years, think that they just need to be into the sports they are betting on, in this case eSports, watch enough games, read the news occasionally and they will be able to win. While you may win a bet once in a while by doing that, especially if you keep it simple and bet at lower odds, preferably on just one or two selections, you would definitely improve your chances of winning if you do the maths right. In fact all professional punters use mathematics and statistics, some of them rely mostly on mathematics.

If you want to try your luck without any risk to your wallet, you can start right here. Test the techniques you will learn on this page in our free tipster competition.

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You can track your bets and see if you actually are as good at placing bets as you think. We even give out $200 in prizes every month. Enough about that, let’s get back to the math!

Amateurs usually choose to rely mostly on their hunch and are often convinced that they will earn big money by simply following their ‘heart’, but that rarely happens in reality. Of course, nobody expects you to become a Nobel winning mathematician in order to become a successful eSports punter, but you will have to do at least a bit of basic mathematics if you wish to be successful.

The House Wins, but not Always

By far the easiest way to beat the house is by claiming a bonus, take a look at our list of recommended betting sites, and choose one for yourself!

Learning the maths comes after the bankroll management, as with proper bankroll management you will know how much you are supposed to wager per week, month or per bet, but the math will help you to choose the appropriate bet or bets. Whenever you are doing the math or trying to spot a bet that is a bargain in terms of odds, remember that the bookmaker is always on the other side and it will always try to earn as much money as possible.

In general, we can expect about a 5% house edge, read more about this in understanding the vig section below.

It is often said that the house always wins. While it is true that in the long term and on average the bookmakers come away with profits, it doesn’t mean that every punter is losing money to the bookies. For the bookmakers to be successful it is only sufficient for the majority of punters to be losing money, they will “allow” some to make money. To put it simple, don’t be worried by the fact that the bookmakers are profitable companies, you can also make profits, if you do your maths right.

Understanding the Vig (House edge)

So, it is true that the bookmakers are profitable, but let’s see where their profit comes from. Traditional bookmakers, not betting exchanges, earn their money through the vigorish, also known as the vig, or the juice.

The best way to explain the vig is through an example. Let’s assume that you’re betting on a Dota 2 match where both teams have the same chances of winning, i.e. they are evenly matched. In that case you should be able to double your money if you bet on one team. Mathematically, if there are two equally probable options than the chances for each option to happen are 50%. Therefore the odds for each option should be 2.00 (1/1 or evens). But they are not, no bookie will offer such odds. Instead, it is a lot more likely that the odds will be 1.92, or 1.94 for one team and 1.91 for the other, or something along those lines.

Example for a 50/50 bet with 1.90 odds for both outcomes:

One player wins 90%, the other player loses 100%. On average this comes to 5% per bet.

That difference between the supposed odds and the odds that are actually offered by the bookmaker is called the vig. The best way to explain it is by assuming that there are two equal options, but it is the same for any wager. Even if we take other markets into consideration, like over/under, map betting or anything else, the situation is the same. We won’t bother you with the mathematical formula, but you can see that the odds are, in a way, stacked against you.

So, if a bookmaker offers odds of 1.92 for the two equally probable options, then the vigorish is 4%, i.e. that is the estimated profit, in the long term, for the bookie. Of course, the bookie might still lose money on an individual market, even if a vig of 4% is applied, but when you consider that there are thousands of betting markets, and the bookies end up profiting from most of them, you will see that the bookies have themselves covered by the vig.

It is much easier to show how the vig works by giving an example of a market where there are just two selections (2-way), but it works just the same for markets which include 3, 4 or more options. When you use the appropriate formula and make the calculation you can see exactly at what percentage the vig is set.

Choosing the best betting site

Comparing the vig offered by two or more bookies will tell you which operator offers more favorable odds. For example, let’s assume that you’re browsing a match between team X and team Y, where one bookmaker offers 2.00 for team X to win and 1.80 for team Y to win, a second bookmaker offers 1.95 for team X and 1.85 for team Y, whereas the third bookmaker offers 1.99 for team X and 1.84 for team Y to win.

The third bookmaker offers the match with the lowest vig, i.e. with the lowest profit margin, which means that it is the most favourable option for punters. However, if you’re looking to place a wager on this match and you think that team X will win, you will probably wish to go with the first bookie, as they give odds at 2.00, whereas if you feel that team Y will win, you will choose the second bookie, as the odds for team Y to win are the highest there.

You can also look at the different odds from bookmakers in our odds section or look at them when writing a tip.

You should always check the odds, both for individual matches, but also in general. If you don’t wish to check the odds for each individual bet, then you will need to choose a bookie that offers the best odds, in general. By doing so, you will know that you won’t get ripped off, but you won’t be able to know for certain that you’re getting the best odds for the bet that you wish to place.

On the other hand, if you are willing to shop around, and especially if you place larger amounts of money per wager, it is wise to check multiple bookies before placing a wager. Check what odds they offer for that particular bet and then place the bet at the bookmaker that offers the highest odds. It’s not rocket science, better odds means more money.

Applying Mathematics to Bonus Offers

Another area where you should apply mathematics, even though it isn’t directly concerned with the odds are the bonuses. If you check the reviews of some or all of the betting operators that we cover, you will notice that most of them offer bonuses which, in many cases, can be claimed by punters who bet on eSports. However, not all bonuses are equally favourable and it is not always the bonus amount that matters most.

For example, if one bookmaker offers a bonus worth £/€/$200 and a second bookmaker offers a bonus that’s worth £/€/$300, it doesn’t mean that the second bonus is better. For example, if the first bonus is a 100% match, whereas the second is a 50% match, you will need to deposit just 200 to get the first bonus, but if you wish to claim a full 300 in the second case, you will need to deposit at least 600.

Then, there’s the wagering requirement. Most bookmakers will require you to wager the bonus amount, or the bonus amount plus the deposit at least once before you can withdraw your winnings. Wagering 400 once and wagering 900 three times (2700) is not the same thing, as you can see. Moreover, sometimes the bookmakers may put a limit on the odds at which you can use your bonus amount. You might not be able to wager your bonus money at odds lower than 1.60, 1.80, or 2.00. Again, it is not the same to have to wager your bonus at 2.00 and at 1.60.

How much can you expect from a bonus? Here we add the term EV or Estimated Value, where we add a few expectations and calculate the average value of bets.

Example for a 100% $100 bonus with 12xB requirements:

You have to wager $1200 in total, since each bet gives the house about 5% you will lose on average $1200 * 0,05 = $60. Leaving you with $140 left and cool $40 extra in your pocket

This, of course, will vary crazily and depends on what the house edge is compared to how good you are at betting.

Always read the small print when you’re considering claiming a bonus, but more importantly do the math and see if the bonus is of any value. In some cases, you may end up losing more money than if you haven’t have claimed the bonus. Smart and successful punters don’t claim unfavourable bonuses, that’s another rule.

It’s All about Making Comparisons

As you can see from what we’ve said above, the basic mathematics is basically about comparisons. You take one figure and you compare it against another and then see which one is more favourable for you. Even if you add more figures into the equation, the principle remains the same. Once you know how to read the odds, you will need to apply the general principles that you have accepted regarding your bankroll.

Choosing the Right Bets – It’s more Difficult than It Seems

Once you learn how to read the odds, you will need to develop a strategy that will help you choose the matches, markets and selections that you are going to wager on. For example, you might wish to place a single wager and you’re not sure whether to back team A to beat team B at odds 1.60 or team X to beat team Y at the same odds. So, both teams you are considering are favourites, but you are not sure which one has higher chances of winning.

The bookmaker obviously feels that both teams have equal chances of winning. But that’s just one bookmaker, the next thing would be to check both matches at multiple bookmakers. So, for instance if all bookmakers value team A at 1.60, but you can find a bookmaker that offers odds of 1.65 for team X to win, maybe you should bet on team X.

But you may think that the chances for team X to win aren’t as high as the chances for team A to win. Again, it depends on what your opinion is based, if it’s just a hunch, a feeling, or you simply have a personal preference or bias towards one team, then that might succeed once, with one bet, but it probably won’t bring you a lot of profit in the long run.

Deciding whether one bet is a better option than another, especially if they are offered at similar or equal odds is a lot more difficult than judging which bookmaker offers better odds, or calculating the vigorish. Picking the best bets is what separates good punters from the very best ones and it takes a lot of practice. Also, you will have to be willing to spend a lot of time and effort analysing potential bets and you will need to read a lot of statistical data.

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