Of course, bookmakers are in the business of setting odds and determining prices which are offered for certain betting events.

If I had to use just one word to describe how bookmakers think…

Image: Cartoonresource (Shutterstock)

When viewing odds in betting exchanges such as Betfair, Betdaq, Smarkets, or WBX, you should understand that it is neither the exchange platform or the traders using them who set the odds.

The fact is that the bookmakers are used as the market guide for traders on the betting exchanges, and it is the bookies who compile and publish their odds weeks in advance of the events in question (sometimes even months), and certainly well before the exchanges even open their markets for trading.

If you have ever calculated odds you will have noticed that the bookmakers’ offers often do not represent the ‘true’ picture, in other words, the ‘true’ mathematically calculated values (the statistically expected values).

Only occasionally (probably in less than half of all cases) are odds close to the statistical expectations of the betting event. However, in the vast majority of games, odds are either considerably higher than mathematically expected or far lower…

Why Is This So?

You have to appreciate that bookmakers do not really intend to predict an outcome (correctly). If you enjoy statistical analysis, then take a little time to do a simple calculation for any league of your choice. Simply convert bookmaker odds into probabilities and compare them to the actual distribution of the results.

Bookmakers have been around for thousands of years in one form or another. Their main goal is of course to make a profit. They price their odds to ensure that sufficient action is taking place on both sides of a bet.

If a bookmaker’s betting odds are not aligned to public opinion then a disproportionately large amount of money will be placed on only one side of a bet. This would be a gamble for the bookmaker. However, bookmakers are not in the business of speculating on an outcome.

The role of bookmakers is, strictly speaking, rather the function of an intermediary, similar to a stockbroker. They take money from various people on various outcomes and after the game is finished they pay out the winners.

In return for this service, the bookies take a “fee” known as the overround.

The bookmakers’ priority is balancing their books

The closer to the kick-off of a game, the more ‘fluid’ the odds become, as salient information such as team news becomes public knowledge, and this then has a knock-on effect with bettors’ opinions being confirmed or changed on the outcome of the match in question. Thus, the odds tend to change more as the start of the match gets nearer and nearer and more money changes hands.

Always remember

1. Bookmakers set odds based on a mixture of statistical probabilities and public opinion.
2. Bookmakers do not speculate (gamble). Their priority is balancing the books.

In an ideal world, bookmakers would like to see the same amount of money (risk) on both sides of a bet outcome. However, utopia is virtually unknown in the world of bookmaking and firms are rarely able to equalise their level of risk on both sides.

Therefore, you will often see a bookmaker adjusting his odds for an event over time. This fluidity aims to achieve an acceptable money line on both sides of the bet outcome.

Please note! Because it is rarely possible to “equalise” the risk on both sides, bookmakers instead look for an “acceptable” level of risk. This is the only ‘gamble’ bookmakers take.

How do Bookies Manage their Risk?

You will have certainly noticed the plethora of various betting offers used by the bookmakers to woo their customers. Unsurprisingly, these are the bets where they expect to make the highest profits (for example, pushing accumulator bets with offers such as, “If team A (usually a short priced favourite) is the one which lets down your five fold, we will return your stake!”) (how generous of them!!).

Bookmakers apply all kinds of marketing tricks to divert the sports bettor into a direction which is most profitable; for them but not for the bettors!

I risk repeating myself but the truth is that bookies’ odds never aim to predict an outcome of a match with utmost accuracy (therefore the calculated probabilities of ‘true’ odds often do not match the betting odds offered in the market). A bookmaker’s main goal is to balance the books and to do this, public opinion is taken into account.

This is the key to bookmaking success. This is the key to sports betting success.

Of course, each sport is different, but in the end bookmaking methods are always the same. Bookmakers make money with these same methods, regardless of the sport or other type of betting event.

• Their books are not perfect.
• They do not have a crystal ball.
• Bookmakers have a business plan!

The bookmakers’ mantra is very simple:

Calculate the statistical chances of the matches for a weekend and set the odds by taking into account the probabilities and public opinion. Collect enough money to pay off losing bets. Keep the profit.

Learn from the Bookmakers!

Bookmakers are not able to balance their books for each single game. To them, it is always about “acceptable” amounts of money (profits or losses) and spreading risk.

The goal of bookmakers is not to predict the outcome of a game correctly. This means that their odds often do not reflect the expected probability distribution.

Bookmakers’ odds usually reflect public opinion about a match and their primary objective is to ensure a well balanced book.

If you wish to become successful with any form of betting you must understand the way of thinking (the business plan) of the bookmakers.

Why? Because these firms survive and thrive from the money they encourage you to lose through nothing more than your own ignorance of how their ‘system’ works.

Managing and following through with the plan is illustrated in the 2017-18 Winter League Report – 35k in 138 Days, where the full performance of our selections is analysed and dissected.

But remember, the best compiled portfolio won’t work without proper bank management and staking.

Juggling a Portfolio of Bets between Bookmakers

Please have a look at the distribution of bets during the 2017-18 Winter League Campaign:

Image 1: 2017-18 Winter League Campaign – Bets per Week of the Year (per round)

Week 38 was the busiest with 24 bets in total, whilst week 50 saw 23 bets. Within a relatively small portfolio of just over 500 bets, the average number of bets per round was 11, but the observed spread was anything between 0 and 24 (2 rounds without bets).

Even with a small portfolio, bank management poses challenges, especially when juggling numerous bookmaker/exchange accounts. Monitoring the balance of each account can become difficult, which may lead to liquidity issues (perhaps not enough in the account) and the constant hassle of moving money between your accounts (or playing with smaller stakes than intended).

Trying to get the highest odds possible in the market all the time becomes unrealistic as the total betting bank would need to be spread over many, many bookmakers.

As harsh as it may sound, you will have to accept that aiming to achieve the highest odds available in the entire market at any moment in time is virtually impossible, and the choice of bookmakers/exchanges has to be limited from the start. I recommend limiting your bookmaker/exchange accounts to a maximum of five or six, and simply choosing best price between them at the time you wish to place a bet.

Here is the list of bookmakers/exchanges we recommend to use in addition to Betfair: –

BetDaq
Matchbook
Smarkets
Pinnacle
William Hill
888Sport

It makes little difference to the results when limiting your accounts to just a handful and you will see evidence of this in our 2017-18 Winter League Report – 35k in 138 Days.

The screenshot below shows the bet placement distribution by bookmaker/exchange.

Image 2: 2017-18 Winter League Campaign – Distribution by Bookmakers/ Exchanges

Lesson 1: Limit your choice of bookmakers/exchanges!

Determining the Stake Size

To determine the stake size there are a few things to consider. Firstly of course, the size of your starting bank. This is an easy one to call – You know what funds you have.

But once you’ve settled on the starting bank, things quickly become a little more complicated…

(1) Distribution of Funds between Bookmakers

You can go to great length and once you have compiled your portfolio carry out following exercise:

• Go to the ‘data’ tab in the HDAFU Tables, copy and paste all applicable matches and amalgamate them in one spreadsheet.
• Go to any odds comparison site of your choice and check the bookmakers that would have been available for you in those matches; log them into your spreadsheet together with the name of the bookmaker/exchange (a hugely time-intensive exercise!)
• Sort the data into chronological order and group it by weeks/rounds.
• Count the number of bets with each bookmaker/exchange in each round.

Once complete, you will be able to use the data to come up with a similar graph to this one:

Image 3: 2017-18 Winter League Campaign – Distribution by Bookmaker/Exchange in more detail

In our example, you can clearly see that Pinnacle had the majority of bets (up to 15 in one round), Betfair and Matchbook were the next most used (up to seven bets per round), followed by 888sport (up to five bets per round), and lastly, William Hill (up to four bets).

Going forwards, the scientific split of our bank for the forthcoming new season based on experience from last season is therefore:

40% Pinnacle: 1,600 units
20% Betfair: 800 units
20% Matchbook: 800 units
10% 888sport: 400 units
10% William Hill: 400 units

But, if you have no past experience it may be harder to estimate which of your chosen bookmakers/exchanges are most likely to have the highest odds when you are ready to place the bets, and how future bets may be distributed between your accounts.

If you have no past figures to guide you, then it is probably best to distribute your betting bank equally between your chosen bookmakers/exchanges. In this case (five accounts), an even split of the starting bank of 4,000 units means 800 units in each account.

Lesson 2: If you cannot calculate the most probable distribution of your bets between the bookmakers of your choice, then simply distribute funds in equal amounts between your accounts!

(2) Distribution of Profits and Losses

The major question is how each betting round is going to perform. Is the portfolio going to make a profit or a loss? Which account will accrue the biggest proportion of profits? Which will be the most high-maintenance, requiring the most re-deposits?

Have a look at our profit/loss distribution over time:

Image 4: 2017-18 Winter League Campaign – Profit/Loss Distribution per Week (per Round)

In total, there were 47 rounds (weeks) of betting. 17 of these (36.2%) finished with losses. (Effectively one losing round in every three).

There were four months (15 rounds) between week 50 (9/12/2017) and week 11 (11/3/2018) where the portfolio experienced a seemingly never-ending rollercoaster ride.

During this time, eight rounds (over 50%!) produced losses as seen in the image above. Those three months were especially difficult on the nerves.

However, this still doesn’t tell us the best stake size. There is also no sense looking at which bookmakers incurred losses, as the past distribution will very likely not repeat itself during the forthcoming new season.

The best guide is to have a look at the profits/losses in relation to the bank size:

Image 5: 2017-18 Winter League Campaign – Profit/Loss in relation to the bank

As you can see, there were three occasions where the bank dropped by more than 12% of its total. In the worst single round (week) the size of the bank contracted by over 15%. Furthermore, we know from Image 1 (distribution of bets per week) that if we are going to employ a similar portfolio of bets in future, that there will be up to 25 bets in a week (round).

We have no idea which of the 25 bets will win and which won’t, and the intention of the staking plan not to be bankrupt after any one week of ‘bad luck’. Also, we don’t want to be in a position after experiencing a ‘bad week’ where we are forced to reduce the size of our stakes. Better to arrange the plan so that we can ride through any longer periods of ‘bad luck’.

We have distributed our funds between accounts but we don’t know which of the chosen bookies/exchanges are going to receive the bets.

(3) Calculating the Stake Size

The ‘scientific’ calculation is as follow:

The average of 12%, 15.2% and 14.6% = 13.9% (rounded: 14%).

Although very unlikely, there may be a run of losses (say three rounds in a row) where the bank is depleted by 14% each time, and should this happen, we still need to continue placing bets without having to reduce the stakes.

As mentioned, we are expecting a maximum of 25 bets in a single round.

25 divided by 86% divided by 86% divided by 86% = 39.3 (risk averse rounded: 40)

1 divided by 40 = 0.025 (= 2.5%)

So, if we risk 2.5% of our betting bank per bet, we will still be able to survive three hefty losing runs without having to reduce the stakes.

The ‘short cut’ calculation is as follow:

If you have no past figures or estimates, take a short-cut and use the following calculation:

• Estimate as best you possibly can the expected maximum number of bets in one betting round
• Double this number
• Divide 1 by this number

Example:

• Expected number of bets: 25
• 25 x 2 = 50
• 1 divided by 50 = 2%

Lesson 3: Limit your stake to 2.5% if you have a portfolio of around 500 bets coming up for one season. If you have a larger portfolio, use your past experience or figures to calculate your maximum stake size as shown above!

Can a Portfolio make Profits during a Rough Patch?

Yes, it can! Our portfolio produced a profit during and despite three very tough months:

Image 6: 2017-18 Winter League Campaign – Analysis of Most Challenging Period

Prior to week 50 the bank size stood at 13,792 units, but after enduring a really volatile period (where more than one round lost in every two) the bank had risen to 23,960 units.

This was only possible by using a strict staking plan in combination with stake ratcheting.

Please remember:

• Limit yourself to just a handful of bookmakers/exchanges: five or six is plenty
• Split your bank (more or less) equally between the chosen accounts
• Limit your individual bet stakes to 2.5% of your entire betting bank (or less if you are expecting more than 25 bets at any betting round)
• Apply and stick strictly to the set rules, and NEVER experiment and/or change your staking midway through a campaign! Once decided. Stick to it!

Get the Full Report on our 2017-18 Winter League Campaign

You may find it helpful to follow the explanations in this article with the help of our Excel monitoring workbook. Not only does it contain the match data and calculates the bet distribution, but includes many more Excel formulas and ideas to help you grasp how to record and control your own betting ventures.

We are sure that you will feel the nominal £5.00 GBP charge is a real bargain.

The size of this .XLSX Excel file is 568KB:

>>> 2017-18 winter league campaign <<<

I hope you enjoyed this article and learned something about the unavoidable randomness of the distribution of bets within a portfolio and how to keep your bank under control despite the inevitable peaks and troughs. However, if you are still unsure on any point, please feel free to ask any questions via the comment section below.

There are all kinds of explanations on the Internet about various odds types, and the majority of them distinguish between fractional, decimal, and moneyline odds.

Image: paffy (Shutterstock)

Unfortunately, this is misleading and mathematically speaking, incorrect. There are only two types of odds, which are unrelated to their displays as fractions, decimals or, as in America, whole numbers.

Just remember those long ago school days (for some of us!)… A fraction, such as 6/5, converts into a decimal 1.2, or vice versa. Both numbers are the same, only written using different formats.

Here are the two main types of odds, including their formulas…

(1) Single-tier – (Net) Return Odds:

Fractional and Hong Kong odds are actually exchangeable. The only difference is that the UK odds are presented as a fractional notation (e.g. 6/5) whilst the Hong Kong odds are decimal (e.g. 1.2). Both exhibit the net return.

The European odds also represent the potential winnings (net returns), but in addition they factor in the stake (e.g. 6/5 or 1.2 plus 1 = 2.2).

(2) Two-tiered – Moneyline Odds: highlighting the amount of money risked, or the amount of money won:

Odds commonly referred to as ‘moneyline’ are mainly US bookmakers odds and also known as American odds. Moneyline means the money wagered either to win 100 units (e.g. -400), or money which will be won from a 100 units wager (e.g. +120).

However, both Indonesian and Malaysian odds, although displayed as decimals are, strictly speaking, ‘moneyline’ odds but their basis is 1 unit and not 100. Whilst the Indonesian odds closely resemble the American moneyline odds, Malaysian odds are a kind of “inverted” Indonesian style, combined with Hong Kong odds.

Although this may all sound pretty confusing, and the odds certainly look very different at first glance (see table below), just have a closer look at the above formulas – all odds are calculated using their net returns (formula for net return: 1/probability – 1) and change their formula at 50% probability (this is what is actually understood under by term ‘money-line’).

European, British, American, Malaysian, Indonesian, and Hong Kong Odds
BETTING ODDS CONVERSION TABLE

Fractional Odds (also known as Traditional or British/UK)

Fractional odds are favoured by bookmakers in the United Kingdom and Ireland.

Fractional odds quote the net return that will be paid out to the bettor, should he win, relative to his stake. Odds of 6/5 (“six-to-five”) imply that the bettor will cash £120 from a £100 stake. Should the punter win, he always receives his original stake back, plus the winnings.

So, if the odds are 6/5 and the stake is £100, then the total return is £220 (£120 winnings plus the original £100 stake).

Odds of 1/1 are known as ‘evens’ or ‘even money’. Not all fractional odds traditionally show the lowest common denominator. Perhaps most unusually, odds of 10/3 are read as “one-hundred-to-thirty”.

Hong Kong Odds (also known as HK Odds)

Image: Scott Maxwell (Shutterstock)

Hong Kong Odds are mainly used by people living in Hong Kong. Until 1997, Hong Kong was under British rule and therefore it should not be a surprise that HK odds closely resemble traditional British odds. The only difference is that HK odds are written in a decimal notation whilst the UK odds use fractions.

Hong Kong odds, as well as their UK counterparts, both quote the net return that will be paid out to the bettor should he win, relative to his stake. Odds of 1.2 in Hong Kong are the same as 6/5 (“six-to-five”) in the UK and both imply that the bettor will earn a net profit of £120 from a £100 stake. Should the punter win, he always receives his original stake back, plus the profit.

It follows that if the HK odds are 1.2 and the stake is £100 then the total return is £220 (£120 winnings plus the original £100 stake).

Decimal Odds (also known as European or Continental)

Decimal odds are standard on betting exchanges and they are favoured in continental Europe, Australia, and Canada.

Decimal odds are equivalent to the decimal value of the fractional odds, plus one. Because decimal odds are simply 1 divided by probability (= 1/probability) they are easier to use in calculations and we therefore favour them for our articles and explanations.

Thus, ‘even odds’ 1/1 are quoted in decimal notation as 2.0; the 6/5 fractional odds (1.2 HK odds) discussed above are quoted as 2.2. Decimal odds quote the net return paid out to the bettor PLUS the original stake.

So if the odds are 2.2 and the stake is €100 then the total return is €220 (€120 winnings including the original €100 stake).

Odds commonly referred to as ‘moneyline’ are the odds which are mainly used by US bookmakers. These odds mean the money wagered either to win 100 units, or the money which will be won from a 100 unit wager.

Please note that both Indonesian and Malaysian odds are also ‘moneyline’ odds although often wrongly referred to just as ‘decimal odds’, probably due to their decimal notation, whilst US moneyline odds are shown in whole numbers.

However, both Indonesian as well as Malaysian odds have the same underlying formulas as the US moneyline odds, only that their basis is 1 unit and not 100.

What does the Betting Odds Convertor do?

• Automatically converts odds into their implied probabilities
• Automatically switches odds between US, decimal, fractional, percentage, Hong Kong, Indonesian, and Malay formats
• Automatically converts probabilities into their corresponding odds
• Automatically displays the net return for each odd type

What Additional Information is included in the Spreadsheet?
Excel formulas, explanations and toggle facilities for the following conversions: –

• Probabilities into Odds
• Net returns into Odds
• Odds into their Implied Probability
• Odds into Net return

Why do I need to know how to convert betting odds
into probabilities and net returns, and vice versa?

In order to compare odds, you need to be able to convert them into implied probabilities and their net returns, because this is the foundation of all odds in the market. Only when you convert odds into their probabilities can you compare them.

Otherwise, how would you possibly know that 6/5 fractional odds, 1.2 HK odds, 2.2 decimal odds, +120 US moneyline, 1.2 Indonesian odds, or -0.83 Malay odds , all stand for a 45.45% chance of success and 120% net return?

Further reading:
Probability, Expectation, Hit Rate, Value, Mathematical Advantage: Explained
Understanding Betting Odds – Moneyline, Fractional Odds, Decimal Odds, Hong Kong Odds, IN Odds, MA Odds

What is the advantage of being able to switch between different betting odds formats?

As you compare prices and look for the best odds available in the market, you limit yourself if you are only at ease with one or two types of betting odds.

For example, you may wish to find the best price for a tennis match, and if you are only comfortable with European style odds, then you probably won’t even consider checking the US market or Asian bookmakers.

However, they may have far better prices on offer; you just simply don’t know because you don’t know how to convert them into probabilities and net returns.

You will never become a winner if you buy your bet at the most conveniently available price, without searching for the best price offered by the market.

Further reading:
Football Betting Odds: Study Comparison Bookmaker vs. Exchanges Odds
Why A Pinnacle Account Is Essential

Why is it important to know the formulas behind odds calculation?

If you calculate your own probabilities and need to check them against the odds offered by bookmakers to find value bets, how on earth would you work this out if you don’t know the formulas behind the odds?

The Internet is full of advice and explanations, but unfortunately the vast majority of information is either wrong or intended to lure you into betting. It is rare to find reliable information on the implied probabilities for odds offered in the markets, or the net returns from the odds.

Furthermore, only people who understand the probabilities behind the odds on offer are able to assess the potential value of a bet.

If you are not skilled in converting betting odds into probabilities you will, without exception, lose money in the long run. Keep reminding yourself: odds stand for probabilities. Bookmakers earn money from gambling, but they do NOT gamble themselves. Neither do they rely on luck. They know how to calculate probabilities and convert them into odds and vice versa. It’s as simple as this.

Therefore, if you want to become a winner, you need to start thinking like a bookmaker, and this means that you simply have to understand probabilities and odds. There is no alternative.

Further reading:
How do Bookmakers Tick? How & Why do they Set Their Odds as they do?
Calculation of Odds: Probability and Deviation

What impact does the knowledge of implied probabilities
and odds conversion have on my betting decisions?

There are two types of gamblers: successful and unsuccessful. The majority of bettors belong to the latter.

If you lose more money than you win, maybe you are basing your betting decisions more on gut feeling than mathematics. Perhaps you place your hard-earned money on a favourite team believing they are in a ‘must win’ match, thinking that they surely cannot lose against the underdog.

You may not even be aware that bookmakers adjust their odds to public opinion, and that odds offered in the market often do not represent their true value.

If your betting decisions are more gambling than anything else, relying on luck, without understanding underlying probabilities of the odds offered, then it is not really surprising that you lose more money than you win.

True understanding and lasting success is based on knowledge, not on ignorance, beliefs, or public opinion.

Only if you develop knowledge of implied probabilities from bookmaker odds, will you be able to check them against your own calculations. Then your betting decisions will be not gambling any more but a planned investment with the goal of a structured and organised increase of your bank.

Further reading:
Heart Beats Brain – Is Accurate Forecasting of Specific Results in Football Matches Possible?
How Bookmakers’ Odds Match Public Opinion

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In 1998, William Hill were the first bookmaker to accept wagers via the Internet, and their online betting platform is one of the most sophisticated in the market. (For sports betting alternatives check out this list).

Their online betting platform is one of the most sophisticated in the market.

Hill also have a tongue-in-cheek reputation for offering odds on literally anything you can think of.

Here is a compilation of our ten favourite left field bets they have accepted, and some notable payouts they have honoured:

Whatever your betting requirements, William Hill has just about every online option you can imagine but if you can think of something weird, wonderful, and original you are encouraged to contact them for consideration and pricing of your proposition. You never know, you might even get some publicity!

How about buying a funny, weird, or eclectic novelty bet from Hill for a family member, or even a colleague during the Office Secret Santa gift giving season?

It would certainly create a topic for debate in the pub, and it doesn’t have to be too expensive. The choice is yours and limited only by your own imagination!

This guide gives you our top 10 things to look out for and check when picking a list of reliable online betting sites with which to invest your hard earned money.

Image: tyrin (Shutterstock)

(1) Free Bets and Bonuses

Many bookmakers and exchanges offer free bets either at the opening of a new account or periodically throughout its lifetime. Some also offer ‘matched deposit’ or ‘deposit top up’ bonuses to increase your war chest with that particular firm.

A good example is Coral Sports who not only provide an account opening free bet, but also a range of offers throughout the season, sometimes limited to particular bet types on particular matches.

They are also very cute in depositing cash into your account a couple of days in advance in the guise of a ‘birthday bonus’. It’s a personal touch – they don’t have to do it, but it gives a good impression when a firm can take advantage of a tiny detail and reward customers without them feeling exploited.

(2) Price Comparison

Buying cheap is definitely a good approach to save money in personal life. However, buying under-priced bets only increases profits for the bookies not for the bettor. Therefore, in betting, the opposite applies. Buy at the highest price possible!

The easiest way of checking the consistency of odds offered by the industry is via an odds comparison site, and the only one to offer both ante post odds plus a full archive for a whole range of bet types and sports is Oddsportal.

Getting the highest odds possible is crucial to the performance of any betting system. Historical odds are crucial for checking the future sustainability of any theory.

You will need to register a username and password to access the full range of bookmakers Oddsportal offers but this is a small price to pay to utilise one of the most useful odds sites out there. If you can’t find the bookmaker or exchange you are looking for amongst their list of almost 80 players, it’s a strong indicator that your prospective choice needs further investigation before you can assume anything about its reputation.

(3) Educational Content

There are two main schools of thought here. Do betting sites offer educational and mathematical articles to help their customers or is it all a smoke screen to make you feel more looked after?

Personally speaking, we place high importance on how bookmakers choose to nurture their customers. Some bookies have absolutely nothing to guide or assist the punter, which lets you know straight away where they stand.

Others, such as Pinnacle, contain a bank of useful articles and information to help the discerning bettor educate himself on the importance of odds, mathematics and statistics.

Any bookie willing to add more transparency to the whole process of betting alchemy is worth taking notice of.

(4) Markets Offered

The terms and conditions of any bookmaker should show you straight away where they are licensed and which countries they are licensed to accept business in.

No two betting sites are the same – they all offer a diversified portfolio of available betting opportunities, but some are more specialised than others.

Betfair continues to lead the betting exchange field (despite the many public criticisms about its business model) purely because it offers the most comprehensive backing/laying opportunities on the market together with unrivalled liquidity. The range of bets it caters for is huge and far outstrips its main rivals such as Matchbook, Smarkets, Betdaq, and WBX.

Recently we received an email from a distressed reader who after a very short time scale (just 2 months!) employing a strategy based on our Home-Draw-Away article, found that without warning several bookmakers (e.g. Boylesport, Stan James, Expekt, Betway, 888Sport, Sportingbet) cancelled his accounts and literally barred him from their e-premises.

Other bookmakers didn’t close his accounts but effectively also ended their relationship by limiting his stakes to ridiculously small amounts such as 2 € per bet.

Our initial response was that bookmakers are free to choose their clients and accounts belonging to customers who do not satisfy their business model are subject to cancellation. This was half accepted by the reader who stated you can read similar suggestions throughout the Web without ever finding a clear explanation but he was insistent and what he really wanted to know from us was WHY?

Therefore, this article attempts to answer in detail the legitimate question as to why customers are banned by bookmakers or accounts are limited.

However, we cannot promise that our conclusions will be agreeable to everyone because sometimes it is better not to know WHY, as dreams are sometimes all too easily shattered by the truth.

Warning: If you prefer to cling on to aspirations of becoming very rich one day with sports betting then perhaps you should stop reading this article now!

Doubtless, life is more bearable if there is some hope of better fortune involved. The reasons why bookmakers close accounts are banal. Using simple logic to interpret the business approach of bookmakers, the bigger picture almost certainly conveys a straightforward message to the masses of people with gambling dreams. Unfortunately, the truth which evolves is contrary to the popular belief system of becoming rich from betting.

Soccerwidow’s survey results for the question “Do you make money with betting?”

This poll has been present on the Soccerwidow site for many months. Let us take a look at the current vote scores to discover whether readers admit to making money from betting:

Survey results (up to November 2012)

So far (as per November 2012), the survey has accumulated a total of 832 votes. Although this is a fairly representative sample, we cannot claim any scientific significance as it has not been carried out under controlled conditions.

Unfortunately, the survey also has a design error. It contains the option, “I make a living from betting”, but fails to quantify voters’ winnings over and above £5,000 (English site) or 5,000 € (German site). Therefore, we have to accept that anyone regularly winning more than £5,000 or 5,000 € per annum had no other option but to tick, “I make a living from betting”. Of course although this is insufficient for survival in most European countries, our readership is worldwide and it may be that 5,000 currency units is enough to live on in some countries.

As we have mentioned before, one of our favourite sites for collecting historical data is www.oddsportal.com, and in our recent article about the concepts for football betting systems we outlined how to set-up an Oddsportal user account and how to optimise the settings.

In this article we concentrate on the rare occasions when it will be necessary to rectify errors in Oddsportal’s information to safeguard against distorted results. At the end, we offer a free Excel spreadsheet download to assist you with this process, plus an exercise to test what you have learned.

Oddsportal Archived Odds Overview

When clicking on any match in the Oddsportal “Archived Odds” section, you will be met with an image similar to the (cropped) screenshot on the right.

Swiss Super League: Xamax v Vaduz 31.8.2008

Click on the picture to enlarge it in a new tab and then use the magnifier provided to increase the image size further.

From first glance this appears to be a fairly ordinary summary of a match that finished 2-2, with a snapshot of the full-time home, draw, and away odds provided by a selection of traditional bookmakers.

At the bottom of each column is the average odds price from all the bookmakers and shown below this, the highest odds on offer.

In the extreme right-hand column is each bookmaker’s “payout” (not their overround) together with the average and highest figures.

All of the figures shown relate to the point in time when the 1×2 odds were suspended by each bookmaker as the match kicked off and went “in-play”.

But there is obviously something very wrong with this image.

Some of you will see the problem immediately but before we tell the rest of you what it is, try and work it out for yourself before moving onto the next page of this article…

Identifying False Football Betting Odds

The odds for the home win are distorted by a rogue price.

It will not take you long to see that the bookmaker, Sportingbet, is shown as offering odds at a price of 4.30, which is far in excess of the others. This is of course also distorting the average odds price, which is currently shown as 1.78.

The big giveaway is the “Payout” column on the right-hand side, which shows 149% for betting on the three highest prices for home, draw and away. This represents a huge arbitrage situation that is very unlikely to occur in 1×2 betting at a fixed point in time before kick-off (ante post betting).

The problem of false odds in an individual game may not sound serious but we have encountered a fair few of these situations during our data collection exercises with various sites and sometimes several in the same league in the same season. In the extreme examples, there is more than one bookmaker mistake in a single match.

Basing your 1×2 football betting system assumptions on a season’s worth of data with several rogue entries, some far worse than the one we have highlighted, may lead you into adopting a set of false belief systems about that particular league and its statistics.

Identifying potential problems therefore becomes necessary before working in any degree of confidence with the raw data.

If you remember from our football betting systems concepts article, we discussed the accuracy issue with mathematics in general.

Looking at a five-year analysis of a particular league’s statistics will sometimes not provide a huge pool of data (e.g. just 882 games in the Swiss Super League in the five seasons 2008-13) and it is here that accuracy with the information becomes more important.

Dictionary definitions of bookmakers

ldoceonline.com (Longman): book‧mak‧er also bookie (informal)
Someone whose job is to collect money that people want to risk on the result of a race, competition etc, and who pays them if they guess correctly.

collinsdictionary.com (Collins): A bookmaker is a person whose job is to take your money when you bet and to pay you money if you win.

merriam-webster.com: A person who determines odds and receives and pays off bets

Encyclopedia definitions of bookmakers

en.wikipedia.org (Wikipedia): A bookmaker, bookie or Turf Accountant is an organization or a person that takes bets on sporting and other events at agreed upon odds. Bookmakers in the United Kingdom focus betting on professional sports, especially horse racing and association football; however, a wider range of bets, including on political elections, awards ceremonies such as The Oscars and novelty bets can also be placed.

investopedia.com: Someone who facilitates gambling, commonly on sporting events, by setting odds, accepting and placing bets, and paying out winnings on behalf of other people. “Bookie” is a slang term for “bookmaker.” Bookies do not usually make their money by placing bets themselves, but by charging a transaction fee on their customers’ bets known as a “vigorish,” or “the vig” (= overround). Bookies may also lend money to bettors.

definitions.uslegal.com: Bookmaking is the practice of laying bets on various possible outcomes of a single event. It is a practice of betting by determining odds, and receiving and paying off bets on sports competitions such as horse racing and the like. The term originates from the practice of recording such wagers in a ledger or a ‘book’ and gives the term bookmaking for the practice of making the book.

Educational gambling web sites explanations of bookmakers

gamblingbox.org: Bookmakers combine a comprehensive knowledge of statistics, a deep understanding of sporting events and other types of events where there is a winner and a loser and the ability to pull in a profit, no matter how an event turns out.

A bookmaker is generally a very accomplished expert in setting odds. Using their own knowledge and the resources they have available, bookmakers will give odds on a given team winning or losing in a sporting event or, in some cases, will give odds on other events, as well. For instance, a bookmaker could theoretically give odds on the outcome of an election and allow people to place bets on that election, if they wanted to.

The way bookmakers do business ensures that they always do come out on top. This doesn’t mean that you can’t win a bet with them, of course, but they are absolute masters at making certain that their own businesses remain profitable while still providing an opportunity for people to wager on sporting events and other events.

sportsbettingis.com: A bookmaker is a company mainly engaged in giving the possibility to make money bets on outcomes of sports events, participation in these bets and paying out of winnings in case outcomes are not in bookmaker’s favor. Events that bets are made on can be not only sports ones but also political, cultural, etc.

The bookmakers always use the mathematics in their operation, especially its following sections: combinatorial analysis, probability theory and statistics. The main task of the bookmakers is to correctly build betting odds.

“To correctly build betting odds” means to correctly evaluate the chances of each outcome and offer the odds bringing profits to the bookmaker. It is not easy to ensure such a balance. It’s a difficult task with hundreds of specialists working with it. Smaller bookmakers look at odds of larger competitors and only introduce small changes.

The Case: Match abandoned in the second half

Image: Stanislav Komogorov (Shutterstock)

When this article was originally written, our last bet of the day was ‘laying’ Mallorca in their La Liga trip to Granada. Before retiring to bed, we checked the score, 2-1 to Granada, with around 30 minutes to play.

Upon checking our Betfair account the following day we were concerned to find the bet had not been settled!? A quick search confirmed fears that the match had been abandoned.

Usually, it’s fog or a floodlight failure, or where the match officials are concerned, a pulled groin muscle, an errant or out of control flag, a clumsy fall, or a slide-tackle from an over-enthusiastic defender.

But no, bizarrely, this abandonment was caused by a flying umbrella, which struck a referee’s assistant in the face and drew blood from his cheek.

After the referee had called a stop to the game the manager of Granada explained in the press conference that it was an unfortunate ‘accident’ and that the poor youth in the Granada section of the crowd was still holding the handle as he was arrested by police.

Much sympathy for the scarred linesman, his apparently innocent assailant and other fans deprived of the result, but where did this leave our bet? We were now in the land of limbo and searching through Betfair’s Terms and Conditions.

Which rules apply?

Like all UEFA leagues, we knew La Liga was faced with 3 options for concluding the affair:

1. replaying the whole match;
2. arranging for the last 30 minutes or so to be played out (probably behind closed doors); or,
3. as it was a Granada fan to ‘blame’, awarding of the match to Mallorca with the customary 3-0 score line.

But how are bets affected by these options and what is the range of different terms and conditions employed by the bookmakers and exchanges in such situations?

Ensure that abandonment and postponement rules are clear before betting

When betting you need to ensure that abandonment and postponement rules are clear especially before embarking on strategies such as cross-market trading, arbitrage or accumulators.

No two bookmakers’ Terms and Conditions are ever identical and for arbitrage or trading it is better to use markets with similar rules for postponement and abandonment or, to know the rules instinctively before making bet selections which could otherwise be detrimentally affected by things such as inclement weather.


The next page concentrates on the different attitudes taken by bookmakers and exchanges…