- Arbitrage betting
**Betting arbitrage**,**surebets**,**sports arbitraging**is a particular case ofarbitrage arising on betting markets due to either bookmakers' different opinions on event outcomes or plain errors. By placing one bet per each outcome with different betting companies, the bettor can make a profit. As long as different Bookmakers are used for arbitrage betting the Bookmakers do not have a problem with this. Each Bookmaker will still make profit due to their calculations.In the bettors' slang an arbitrage is often referred to as an

**arb**; people who use arbitrage are called**arbers**. A typical arb is around 2%, often less, however 4%-5% are also normal and during some special events they might reach 20%.Arbitrage Betting involves relatively large sums of money (stakes are bigger than in normal betting) while another variety,

**betting investment**, means placing relatively small bets systematically on overvalued odds most of which will lose but some win thus making a profit.The best way of generating profit, which has been established in Britain via sports arbitrage, consists of 'key men' employing others to place bets on their behalf, so as to avoid detection increase accessibility to bookmakers. This allows the financiers or key arbers to stay at a computer to keep track of market movement.

Bookmakers have become wise to such activities with Betfred employing widespread banning in operation notably in yorkshire where Arbitrage appears to be particularly common. Currently it is believed only one group is operating on a large level, the members of which group have been given nicknames such as: big tom, scotch n tall, satchel lad etc. Names released by william Hill spokespeople yorkshire.

**Arbitrage in theory**There are a number of potential arbitrage deals. Below is an explanation of some of them including formulas and risks associated with these arbitrage deals. The table below introduces a number of variables that will be used to formalise the arbitrage models.

**Arbitrage using bookmakers**This type of arbitrage takes advantage of different odds offered by different bookmakers. Assume the following situation:

We consider an event with 2 possible outcomes (e.g. a tennis match - either Federer wins or Henman wins), the idea can be generalized to events with more outcomes, but we use this as an example.

The 2 bookmakers have different ideas of who has the best chances of winning. They offer the following Fixed-odds gambling on the outcomes of the event

For an individual bookmaker, the

**sum of the inverse of all outcomes**of an event will always be greater than 1.$o\_1^\{-1\}\; +\; o\_2^\{-1\}\; >\; 1$

As they are in this case: $1.25^\{-1\}\; +\; 3.9^\{-1\}\; =\; 1.056$ and $1.43^\{-1\}\; +\; 2.85^\{-1\}\; =\; 1.051$

The fraction above 1, is the bookmakers return rate, the amount the bookmaker earns on offering bets at some event. Bookmaker 1 will in this example expect to earn 5.6% on bets on the tennis game. Usually these gaps will be in the order 8 - 12%.

The idea is to find odds at different bookmakers, where the sum of the inverse of all the outcomes are below 1. Meaning that the bookmakers disagree on the chances of the outcomes. This discrepancy can be used to obtain a profit.

For instance if one places a bet on outcome 1 at bookmaker 2 and outcome 2 at bookmaker 1:

$1.43^\{-1\}\; +\; 3.9^\{-1\}\; =\; 0.956$

Placing a bet of 100$ on outcome 1 with bookmaker 2 and a bet of $\$100*1.43/3.9\; =\; 36.67$ on outcome 2 at bookmaker 1 would ensure the bettee a profit.

In case outcome 1 comes out, one could collect $r\_1\; =\; \$100\; *\; 1.43\; =\; \$143$ from bookmaker 2. In case outcome 2 comes out, one could collect $r\_2\; =\; \$36.67\; *\; 3.9\; =\; \$143$ from bookmaker 1. One would have invested $136.67, but have collected $143, a profit of $6.33 (%4.6) no matter the outcome of the event.

So for 2 odds $o\_1$ and $o\_2$, where $o\_1^\{-1\}\; +\; o\_2^\{-1\}\; <\; 1$. If one wishes to place stake $s\_1$ at outcome 1, then one should place $s\_2\; =\; s\_1\; *\; o\_1\; /\; o\_2$ at outcome 2, to even out the odds, and receive the same return no matter the outcome of the event.

Or in other words, if there are two outcomes, a 2/1 and a 3/1, by covering the 2/1 with $500 and the 3/1 with $333, one is guaranteed to win $1000 at a cost of $833, giving a 20% profit. More often profits exists around the 4% mark or less.

Reducing the risk of human error is vital being that the mathematical formula is sound and only external factors add "risk". Numerous online arbitrage calculator tools exist to help bettors get the math right.

**Back-lay sports arbitrage**Betting exchanges open up a new range of arbitrage possibilities since it is possible to back as well as lay an event. Arbitrage using only the back or lay side might occur on betting exchanges. It is in principle the same as the arbitrage using different bookmakers. Arbitrage using back and lay side is possible if a lay bet provides lower odds than a back bet. (Of course, the commission of the bookmaker must be included into calculations.)

**Bonus sports arbitrage**Many

bookmaker s offer first time users a signup bonus in the range $10 - $200 for depositing an initial amount. They typically demand that this amount is wagered a number of times before the bonus can be withdrawn.**Bonus sport arbitraging**is a form of sports arbitraging where you hedge or back your bets as usual, but since you received the bonus, a small loss can be allowed on each wager (2-5 %), which comes off your profit. In this way the bookmakers wagering demand can be met and the initial deposit and sign up bonus can be withdrawn with little loss. See alsomatched betting .The advantage over usual

**betting arbitrage**is that it is a lot easier to find bets with an acceptable loss, instead of an actual profit. Since most bookmakers offer these bonuses this can potentially be exploited to harvest the sign up bonuses.**Making money:**By signing up to various bookmakers, it's possible to turn these 'free' bets into cash fairly quickly, and either making a small arbitrage, or in the majority of cases, making a small loss on each bet, or trade. However, it is relatively time consuming to find close matched bets or arbs, which is where an arb / close matched bet service is useful.

**Drawbacks:**As well as spending time physically matching odds from various bet sites to exchanges, the other draw back with bonus bagging / arb trading in this sense is that often the free bets are 'non-stake returned'. This effectively reduces the odds, in decimal format, by 1. Therefore, in order to reduce 'losses' on the free bet, it is necessary to place a bet with high odds, so that the percentage difference of the decrease in odds is minimalised.

**Arbitrage in practice**If in theory sports arbitrage is very interesting, in practice there are some points that to be taken into account.These days there is rarely any profits to be made with arbitrage due to scanning software used by bookmakers.

**Risks**There are several risks when doing sports arbitrage.

**Making errors:**One of the main risk is to make an error when placing the bets. This might seems curious, but in the excitement of the action and due to the high number of bets placed, it is not uncommon to make mistake (like traders on financial markets). For example you bet on the wrong team, or you don't have enough money on one of the account to place one of the bet etc. Those errors might temporarily have an important impact. On the long term, they don't because sometimes those errors will make you earn more, and sometimes make you lose.**Bet cancellation:**One of the most feared thing by arbers is bet cancellation. If you have placed the bets to make an arbitrage, and if one bookmaker cancel your bet, you are in a bad position, because your are actually betting with all the risks implied. In that case, it is better to bet once more on the bet that has been cancelled to minimize the risk. Cancellation of a bet happens when an error has been made by the bookmaker. When you have some experience, you will detect the situation were it will happen. In most of the case it happens when there is a very high returns.**Money transfer**You must take care if you don't want to lose all your benefits in money transfer from one bookmaker to another as money transfer imply often a commission. You must choose a cheap method to transfer funds (several exist, the most used being MoneyBooker and Neteller).

**Currencies**Do not try to do arbitrages between several accounts with different currencies (as currencies fluctuate). Keep on using the same currency.

**Limitations**Over the time, some bookmakers will limit your bets. Thus making the activity less profitable or harder.

**Profitability**If you have a sufficient capital, enough time and the appropriate tools, you can make a lot of money (several hundreds Euros/pounds/dollars per month).

**Surebets detection**One of the most difficult thing is to detect the surebets. Several sites offer this service. Cost vary a lot. Some are free, other can cost up to 150 euros per month.It is probably wise to start with free services or use the free demo version for the others.

**ee also***

Advantage gambling

*Dutch book

*Mathematics of bookmaking **External links*** [

*http://www.sports-arbitrage.info Sports Arbitrage Betting Information*]

* [*http://www.sportsarbitrageguide.com Sports Arbitrage Guide and News*]

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