What Do Negative Odds Mean
Money lines (also called American Odds) are one of the most common ways to bet on sports. They do not use a point spread, and are straight-up bets on who will win the game or event.
If the odd is negative (-) it means that outcome is more likely to happen and placing a bet on that outcome would payout less than the amount you wagered, while a positive (+) odd shows that the outcome is less likely to happen and it would pay out more than the amount you wagered. The short answer to the question of 'what do the plus and minus signs before the odds number mean' is: a minus sign indicates a favourite to win, while a plus sign indicates an underdog. For instance - let's say that a team is -145 to win a game. That's also equivalent to fractional odds of 2/1 and decimal odds of 3. A negative money line represents the amount that you would have to bet to win $100 if you were correct. For example, a -200 money line means you would win $100 if you bet $200 and won. It is also equivalent to fractional odds of 1/2 and decimal odds of 1.5. $begingroup$ @Angel The positive/negative aspect of the log odds is related to the directionality of your original comparison. Here, it looks like Relapse compared to a baseline of Primary, so the negative log(OR) of -4.09 indicates that PML is less frequently mutated in Relapse than Primary.
To properly explain how to bet the money line, the first thing to understand is the difference between a negative and positive money line. Both money lines use $100 as the basis point for calculating payouts, but they’re calculated differently.
How to Calculate Money Line Payouts
A negative money line is indicated with a ‘-‘ in front of a number, like -230. The number represents the amount of money that would need to be wagered in order to win $100 in profit. So, a -230 money line would require a wager of $230 to win $100 more, for a total payout of $330 ($230 wager + $100 profit). Of course a $230 bet is not required, it’s just the basis for calculating the payout. With odds of -230, a $23 bet would return $10 in profit, or a $2.30 bet would return $1 in profit.
A positive money line is indicated with a ‘+’ in front of a number. In this case, the number represents the amount that would be won from a $100 wager. So, a +170 money line means that a $100 wager would return $170 in profit, for a total payout of $270 ($100 wager + $170 profit = $270). A bet of $10 would result in a $17 profit, and a total payout of $27 ($10 wager + $17 profit = $27).
More About Negative Lines
Generally a negative money line represents the favored team in a match. There are exceptions to this and we’ll discuss that later. For now, think negative money line = favorite.
In most two-team games like football, baseball or soccer, one team will have a negative money line, and the opponent will have a positive money line. The team with a negative money line is the favorite, and the team with the positive money line is the underdog.
Example:
- New England Patriots +140
- Indianapolis Colts -160
In this case, the Colts are the favorite. It would take a bet of $16 to win $10 in profit, for a total payout of $26 ($16 wagered + $10 profit = $26). For the Patriots, as the underdog, it would only take a bet of $10 to win $14 in profit, for a total payout of $24 ($10 wager + $14 profit = $24).
Since the favored team is considered more likely to win, and because no handicap is being used, it takes a larger wager to win a smaller profit on them.
More About Positive Lines
In a 2-team game where one team has a positive money line, they are always the underdog. Since they’re underdogs, it requires a smaller wager to win a larger profit.
Example:
- Pittsburgh Penguins +130
- New York Rangers -150
In this case, a bet of $10 on the Penguins would result in a $13 profit if they win, for a total payout of $23 ($10 wager + $13 profit = $23). For the Rangers, it would take a bet of $15 to win $10 in profit, for a $25 total payout ($15 wager + $10 profit = $25).
Games Where Both Teams Are Negative
In games like baseball or football, it’s not uncommon to see both teams represented with a negative money line. When this happens, it means the teams are very closely matched.
For Example:
What Do Negative Odds Mean In Betting
- New York Yankees -113
- Boston Red Sox -107
In the scenario above, the game is considered very close, with a slight edge towards the Yankees. It would require a bet of $113 to win $100 on the Yankees, or $107 bet to win $100 on the Red Sox.
Sports With Multiple Teams or Competitors
Of course there are sports with multiple competitors in a single event, like horse racing, Olympic events, and golf. This is also the case in futures bets, where the handicapper is choosing between multiple teams to win a seasonal champion.
In this case, there will generally be one favorite, indicated with a negative money line, and the rest of the field will have positive money lines. Sometimes, when there are no clear favorites, there may not be a single competitor with a negative money line. In this case, the competitor with the lowest positive money line is favored.
Example:
Tiger Woods +600
Phil Mickelson +850
Martin Kaymer +1300
Lee Westwood +1600
Steve Stricker +2300
In this case, Tiger Woods is the favorite, but he has a positive money line. A bet of $10 on him would result in a $60 profit if he wins. A bet of $10 on Steve Stricker would result in a $230 profit if he were to win.
Converting Moneyline Odds to Fractional Odds
We all learned how to do fractions in elementary school, and once you understand money line odds, the conversions are simple.
How to Convert Positive Money Lines to Fractional Odds
To convert a positive money line into fractional odds, divide the number in the money line by 100.
Examples:
- +250 Money Line: 250/100 = 2.5/1 (5/2) Fractional Odds
- +400 Money Line: 400/100 = 4/1 Fractional Odds
- +650 Money Line: 650/100 = 6.5/1 (13/2) Fractional Odds
How to Convert Negative Lines to Fractional Odds
To convert negative money lines to fractional odds, divide the number in the money line by 100. Put that number on the right side of a fraction which begins with ‘1/’. Some numbers on the right side of the fraction will have a decimal in them. Since decimals are not used in fractional odds, they are removed by multiplying both numbers in the fraction by 2.
Examples:
- -200 Money Line: 200/100 = 2. Put the 2 on the right side of a fraction beginning with 1/, resulting in fractional odds of 1/2.
- -350 Money Line: 350/100 = 3.5. Put the 3.5 on the right side of a fraction beginning with 1/, resulting in fractional odds of 1/3.5. Multiply both numbers in the fraction by 2 to remove the decimal = 2/7 fractional odds.
- -650 Money Line: 650/100 = 6.5. Put the 6.5 on the right side of a fraction beginning with 1/, resulting in fractional odds of 1/6.5. Multiply both numbers in the fraction by 2 to remove the decimal = 2/13 fractional odds.
Converting to Decimal Odds
Positive money lines show the profit that would be won from a $100 bet, not including the original wager. Negative money lines show the wager required to win $100 in profit. Neither of these reflect the total payout. This is different in decimal odds.
Using decimal odds, a handicapper can easily calculate their entire payout. For example, a team with decimal odds of 3.0 would be multiplied by the wager amount to calculate the entire payout. A $20 bet with 3.0 decimal odds would pay out a total of $60 ($20 x 3.0 = $60).
The calculation to convert a positive money line to decimal odds is different from the calculation of a negative money line to decimal odds. Here’s how they convert:
How to Convert a Positive Money Line to Decimal Odds
To convert a positive money line to decimal odds, divide the money line by 100, then add 1.
Examples:
- +200 / 100 = 2 + 1 = 3.0 Decimal Odds
- +350 /100 = 3.5 +1 = 4.5 Decimal Odds
- +625 / 100 = 6.25 +1 = 7.25 Decimal Odds
Negative Lines to Decimal Odds
To convert a negative money line to decimal odds, start with the number 100 and divide it by the number in the money line, then add 1.
Examples:
- -200 Money Line: 100 / 200 = .5 +1 = 1.5 Decimal Odds
- -350 Money Line: 100 / 350 = .286 +1 = 1.286 (1.29) Decimal Odds
- -625 Money Line: 100 / 625 = .16 +1 = 1.16 Decimal Odds
What Does +500 Odds Mean
Pros & Cons of Money Line Bets
When compared to a point spread, for the underdog, the benefit of a money line bet is the increased odds a handicapper receives. For the favorite, the benefit is that no handicap is given to the underdog, making it more likely their bets will win.
For the underdog, the negative is that they don’t receive a handicap, making it more difficult to win these bets. For the favorite, the negative is that the punter receives lower odds than they do when they’re giving up points on the spread.
Comparing the money line to the run line in baseball or puck line in hockey, the benefit ‘can’ be slightly reduced juice (vig, or commission). For example, many online sportsbooks charge a 5% vig on baseball or hockey money line bets. However, it’s harder to find reduced juice on run lines and puck lines, where punters normally pay 10% vig. Over the course of a season and a lot of bets, 5% can be the difference of being a winning or losing handicapper.
Money lines are the most popular way to bet on MLB baseball and NHL hockey, so the lines can move dramatically from the time they’re posted to the time they close. If you know how to watch lines move and predict where they’re going, money lines can offer a lot of value. For example, when betting on big underdogs in baseball, the best money line odds can often be found as soon as the lines open – before other bettors see the same value you do and bring the odds down. For big favorites, it’s often best to wait until 1-2 hours before game time. For big games with a lot of action, sharp bettors often place big wagers just before a game, which can also create optimal betting opportunities.
For casual bettors, money line bets are easier to make. There is no point spread to mull over, and all that matters is that you choose the winner.
Fixed-odds betting is a form of wagering against odds offered by a bookmaker or an individual or on a bet exchange. It involves betting on an event in which there is no fluctuation on the payout. In Australia, the practice is usually known as 'SP betting'.
Calculating fixed odds[edit]
It is customary with fixed-odds gambling to know the odds at the time of the placement of the wager (the 'live price'), but the category also includes wagers whose price is determined only when the race or game starts (the 'starting prices'). It is ideal for bookmakers to price/mark up a book such that the net outcome will always be in their favour: the sum of the probabilities quoted for all possible outcomes will be in excess of 100%. The excess over 100% (or overround) represents profit to the bookmaker in the event of a balanced/even book. In the more usual case of an imbalanced book, the bookmaker may have to pay out more winnings than what is staked or may earn more than mathematically expected. An imbalanced book may arise since there is no way for a bookmaker to know the true probabilities for the outcome of competitions left to human effort or to predict the bets that will be attracted from others by fixed odds compiled on the basis personal view and knowledge.
With the advent of Internet and bet exchange betting, the possibility of fixed-odds arbitrage actions and Dutch books against bookmakers and exchanges has expanded significantly. Betting exchanges in particular act like a stock exchange, allowing the odds to be set in the course of trading between individual bettors, usually leading to quoted odds that are reasonably close to the 'true odds.'
'The best of it'[edit]
In making a bet where the expected value is positive, one is said to be getting 'the best of it'. For example, if one were to bet $1 at 10 to 1 odds (one could win $10) on the outcome of a coin flip, one would be getting 'the best of it' and should always make the bet (assuming a rational and risk-neutral attitude with linear utility curves and have no preferences implying loss aversion or the like). However, if someone offered odds of 10 to 1 that a card chosen at random from a regular 52 card deck would be the ace of spades, one would be getting 'the worst of it' because the chance is only 1 in 52 that the ace will be chosen.
In an entry for L'Encyclopédie (the Enlightenment-era 'French Encyclopedia'), Denis Diderot cites a similar example in which two players, Player A and Player B, wager over a game of dice that involves rolling two six-sided dice. Player A wins if the dice add up to 12, of which there is only one possible case. Player B wins if the dice fall in any other combination, of which there are 35 possibilities.[1] It is mathematically disadvantageous to make a bet if one gets'the worst of it.' Accordingly, for the bet to be 'fair,' the amount each player could potentially lose or gain from the wager should be adjusted, depending on the odds of their success.
Laying odds[edit]
When making a bet in which one must put more at risk than one can win, one is laying the odds. Rational bettors will do so only if the actual chances of an adverse outcome are low enough that the expected outcome even after deduction of taxes and any transaction costs is favorable to the person placing the bet. For example, if one bets $1,000 that it will rain tomorrow and can win only $200 but can lose the entire $1,000, one is laying odds that will rain tomorrow. Laying odds is reflected in the colloquial expression '[I would] dollars to doughnuts' — with which the speaker is expressing a willingness to risk losing something of value in exchange for something worthless, because winning that bet is a certainty.[2]
Lay betting[edit]
'Lay betting' is a bet that something will not happen, so 'laying $50 on a horse' is betting the horse will not win. Bookmakers sell bets based on the odds of a specific outcome, but lay betting allows the bettor (in some English-speaking countries, the 'punter') to reverse roles with the bookmaker, using odds to sell the opposite outcome to the bookmaker. In this context, 'lay' is used in the sense of 'layman', i.e., a bet sold by someone who does not sell bets professionally.
Types of odds offered[edit]
There are three widely used means of quoting odds:
Fractional odds[edit]
Favoured by bookmakers in the United Kingdom and Ireland and common in horse racing, fractional odds quote the net total that will be paid out to the winning bettor relative to the stake. The term 'fractional odds' is something of a misnomer, especially when visually reinforced by using a slash (as opposed to, e.g., a colon or the word 'to' or 'on') to separate a potential gain from the amount that a bettor must wager in order to receive it upon a win, because the 'fraction' in question represents not the odds of winning or even the reciprocal of the odds of winning but rather the fraction (for any odds longer than 'even money' or chances of winning less than 50%, an improper fraction) of the amount at stake that the upside outcome represents. This fraction may be derived by subtracting 1 from the reciprocal of the chances of winning; for any odds longer than 'even money,' this fraction will be an improper one.[3][4] Odds of 4:1 ('four-to-one' or less commonly 'four-to-one against') would imply that the bettor stands to make a £400 profit on a £100 stake. If the odds are 1:4 (read 'one-to-four', or alternatively 'four-to-one on' or 'four-to-one in favor'), the bettor stands to make £25 on a £100 stake. In either case, against or on, should he win, the bettor always receives his original stake back, so if the odds are 4:1 the bettor receives a total of £500 (£400 plus the original £100). Odds of 1/1 are known as evens or even money.
Not all fractional odds are traditionally read using the lowest common denominator. Perhaps most unusual is that odds of 10:3 are read as 'one-hundred-to-thirty'.
Fractional odds are also known as British odds,UK odds,[5] or, in that country, traditional odds.
Decimal odds[edit]
Favoured in Continental Europe, Australia, New Zealand and Canada, decimal odds differ from fractional odds by taking into account that the bettor must first part with their stake to make a bet; the figure quoted, therefore, is the winning amount that would be paid out to the bettor.[4][6] Therefore, the decimal odds of an outcome are equivalent to one plus the decimal value of the fractional odds; in the absence of built-in house advantage to cover overhead, profit margins, or (for an illegal enterprise) compensation for the fact that both chances of prosecution and penalties in the event of conviction tend to be higher for bookmakers than for clients, the decimal odds associated with a given outcome would be the decimal expression of the reciprocal of what the offering party assesses to be the outcome's chance of occurring.[7] Thus, even odds 1/1 are quoted in decimal odds as 2. The 4/1 fractional odds discussed above are quoted as 5, while the 1/4 odds are quoted as 1.25. It is considered to be ideal for parlay betting because the odds to be paid out are simply the product of the odds for each outcome wagered on.
Decimal odds are also known as European odds, digital odds or continental odds and tend to be favoured by betting exchanges because they are the easiest to work with for trading, in this case the purchase and sale of upside and downside risk.[5]
Moneyline odds[edit]
Moneyline odds are favoured by United States bookmakers and as such are sometimes called American Odds.[4] There are two possibilities: the figure quote can be either positive or negative. Moneyline refers to odds on the straight-up outcome of a game with no consideration to a point spread.
- Positive figures
- If the figure quoted is positive, the odds are quoting how much money will be won on a $100 wager (done if the odds are better than even). Fractional odds of 4/1 would be quoted as +400 while fractional odds of 1/4 cannot be quoted as a positive figure.
- Negative figures
- If the figure quoted is negative, the moneyline odds are quoting how much money must be wagered to win $100 (this is done if the odds are worse than even). Fractional odds of 1/4 would be quoted as −400 while fractional odds of 4/1 cannot be quoted as a negative figure.
- Even odds
- Even odds are quoted as +100 or −100. Some but not all bookmakers display the positive symbol.
Odds conversion[edit]
To convert fractional odds to decimal, take the fractional number, convert it to decimal by doing the division, and then add 1. For example, the 4-to-1 fractional odds shown above is the same as 5 in decimal odds, while 1-to-4 would be quoted as 1.25.
The method for converting moneyline to decimal odds depends on whether the moneyline value is positive or negative. If the moneyline is positive, it is divided by 100 and add 1. Thus, +400 moneyline is the same as 5.0 in decimal odds. If the moneyline is negative, 100 is divided by the absolute moneyline amount (the minus signed is removed), and then 1 is added. For example, −400 moneyline is 100/400 + 1, or 1.25, in decimal odds.
| Decimal | Fractional | Moneyline | Win% (to break even) | Return (minus stake) |
|---|---|---|---|---|
| 1.01 | 1/100 | −10,000 | 99.01% | 1.00% |
| 1.11 | 1/9 | −900 | 90.00% | 11.11% |
| 1.33 | 1/3 | −300 | 75.00% | 33.33% |
| 1.50 | 1/2 | −200 | 66.67% | 50.00% |
| 2.00 | 1/1 | ±100 | 50.00% | 100.00% |
| 3.00 | 2/1 | +200 | 33.33% | 200.00% |
| 4.00 | 3/1 | +300 | 25.00% | 300.00% |
| 10.00 | 9/1 | +900 | 10.00% | 900.00% |
| 101.00 | 100/1 | +10,000 | 0.99% | 10,000.00% |
See also[edit]
References[edit]
- ^'Wager'. University of Michigan Library. Retrieved 1 April 2015.
- ^Listening to America, Stuart Berg Flexner (Simon and Schuster, New York, 1982).
- ^'Betting School: Understanding Fractional & Decimal Betting Odds'. Goal. 10 January 2011. Retrieved 27 March 2014.
- ^ abcCortis, Dominic (2015). Expected Values and variance in bookmaker payouts: A Theoretical Approach towards setting limits on odds. Journal of Prediction Markets. 1. 9.
- ^ ab'Betting Odds Format'. World Bet Exchange. Archived from the original on May 2, 2014. Retrieved 27 March 2014.
- ^D., Chris. 'What is Fixed odds betting and Due Column betting?'. TBR. Retrieved 27 March 2014.
- ^'Fractional Odds'. betstarter.com/. Archived from the original on April 2, 2014. Retrieved 27 March 2014.