SPORTSBETTING MONEYLINE QUESTION

Let's say the favorite in a baseball game is -170 & the underdog is +145. I used to think that the vig free odds would be right in the middle. (-157.5) (+157.5). My math is showing that this is not correct. I'm seeing that the favorite would be a higher minus number while the underdog would go up more than the half way point. If the favorite is -170, what would the juice free line be? What would the +145 line be if it were actually juice free?

For example if two teams are both -110 to win. -100 is juice free.

Could you explain how you came up with the number so I could translate other odds to juice free?

Another thing, do casino edges go up with higher numbers? Such as -110 -110 seems to be a 4.54% house edge. Is the edge the same on a -170 +140? Or does the house edge go up when there's a bigger favorite? Say a game has the favorite as -550 & +425. Is this a worse bet than -110 -110?

Quote: roudy12345

Let's say the favorite in a baseball game is -170 & the underdog is +145. I used to think that the vig free odds would be right in the middle. (-157.5) (+157.5). My math is showing that this is not correct. I'm seeing that the favorite would be a higher minus number while the underdog would go up more than the half way point. If the favorite is -170, what would the juice free line be? What would the +145 line be if it were actually juice free?

For example if two teams are both -110 to win. -100 is juice free.

Could you explain how you came up with the number so I could translate other odds to juice free?

Another thing, do casino edges go up with higher numbers? Such as -110 -110 seems to be a 4.54% house edge. Is the edge the same on a -170 +140? Or does the house edge go up when there's a bigger favorite? Say a game has the favorite as -550 & +425. Is this a worse bet than -110 -110?
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Great post. I don’t know the exact formula, but ‘juice free’ would be closer to the lower number than the higher number.

There are others here (I think) that will answer exactly for you. My guess on -170/+145 is 155

Quote: roudy12345

Another thing, do casino edges go up with higher numbers? Such as -110 -110 seems to be a 4.54% house edge. Is the edge the same on a -170 +140? Or does the house edge go up when there's a bigger favorite? Say a game has the favorite as -550 & +425. Is this a worse bet than -110 -110?
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I wondered about this for a long time, but somebody finally indicated that as the chances of winning:losing move away from 50% either way, it is mathematically necessary to spread out the numbers to keep the edge the same. I never looked into it

as far as what is closest to no juice, they say that the odds get adjust to encourage one bet over the other depending on how much action one side is getting. They want a better balance in the action. In other words, if too many people are betting on the Yankees, which happens a lot, then the odds get adjusted for less juice to the other team odds, but never to be 'no juice'. I might be wrong, but I think this factor often determines it.

https://en.wikipedia.org/wiki/Vigorish

Quote: roudy12345

Another thing, do casino edges go up with higher numbers? Such as -110 -110 seems to be a 4.54% house edge. Is the edge the same on a -170 +140? Or does the house edge go up when there's a bigger favorite? Say a game has the favorite as -550 & +425. Is this a worse bet than -110 -110?
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Casino edge should not change with higher numbers. It might change with the spread in the lines. A "dime line" of -120 and +110 has less room for profit than a "quarter line" of -135 and +110. However, sports is not like other bets where the outcome is random based on cards, dice, or wheels. The stated goal of lines is to balance action on both sides. This can be hard to do when one team is so favored that people are not taking action on the dog at any price.

But the "stated goal" is not the real thing. Sportsbooks are fine with out of balance action if they are on the right side of things. Price a favorite too high so they will not cover, meanwhile give enough of a moneyline on the dog to make it look juicy. Also, at the moment they seem to be profiting by pushing parlays. The average bettor may be getting too good to make it on straight bets so they push the parlays. They have better edge there.

In my experience, the vig is slightly lower when the lines are unbalanced. In your example, the vig is 3.7% on a -550 & +425 line.

Ultimately, I'm trying to figure out what the number is exact. That way I can figure out what the winning/loss percentage actually is. When you type in -170 into a calculator it converts into a percentage based on -170 being the fair number. Since -170 includes vig, I'm getting a skewed percentage. Hopefully someone can show me the math! The more I think about it, what you're saying makes sense on your guess. Just trying to be able to calculate advantaged play on sportsbets with lines moving and so on.

Quote: roudy12345

Ultimately, I'm trying to figure out what the number is exact. That way I can figure out what the winning/loss percentage actually is. When you type in -170 into a calculator it converts into a percentage based on -170 being the fair number. Since -170 includes vig, I'm getting a skewed percentage. Hopefully someone can show me the math! The more I think about it, what you're saying makes sense on your guess. Just trying to be able to calculate advantaged play on sportsbets with lines moving and so on.
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There is no exact formula for house edge on a sports line. If the book sets the line wrong, the bettors can have an advantage. If the match is fixed, the house can also find themselves at a disadvantage. You can only calculate the house edge if you assume that the line was set to make the book indifferent to who wins. That is, the line attracted the right balance of money on both sides.

In a parimutuel pool, the house sets no odds. They calculate the odds after the final betting so they don't care which horse wins. You can calculate the takeout/vigorish for a sports book only if you assume the line is set to attract the right balance of action. It gets more complicated, because some books might not want the action balanced. They want to be exposed to one side or the other. If they do this right, their house edge increases. There is no exact calculation for vigorish unless you make further assumptions. The book targets a certain vig, but they cannot guarantee a certain vig in the same way a parimutuel pool can.

Let's assume that you and I want to make a private bet on an event and we ask a sports book to act as an intermediary. The book takes 5% of the action as the vigorish. I put up $400 and you put up $100. What will the payout be if the book wants the bet to pay out the same amount no matter who wins? How does this translate to the balanced line.

This is a simple calculation. You will understand the line better if you can work through this problem yourself.

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I found this vig calculator - linked - that I think answers the very interesting question from the OP - I have also thought about this question

I do not know the formula they use - Mental prolly does - but anyway you don't need the formula since the link provides the answer without it

today I saw an MLB game that was priced -240 on the fave and +195 on the dog -

when I put that into the vig calculator I can see that the vig is 4.49% - right about what the books want for the vig

but my question, and I think the OP's is if you have one side priced - how do you price the other side

with the vig calculator you can just play with and make a guess until you come out with about the typical vig on a sports bet which is 4.55%

so, for example if I want to know the other side when the fave is priced at -375 I took a guess on the dog at +255 and it shows the vig as being 7.12%

that's too high so I kept playing with it and when I priced the dog at +290 the vig is 4.59% which is right about what the books want

you can also use the calculator to compare the deals offered by the various books - and find which books have the lower vig

.per the OP's question a juice free bet would be the same number on both sides - one side positive and one side negative

so, if a bet on the fave is -200 that means he will bet $200 to win $100 and the probability is that he will win 2 out of 3 times to break even - 2 times he will bet $200 to win $100 and will win $200 and one time he will lose $200 - breaking even

the bettor on the dog at + 200 will win one out of 3 times - 2 times he will lose $100 and one time he will win $200 - breaking even

this is the expectation intended to reflect the true probability - but it does not necessarily reflect the reality of what will happen



https://oddsjam.com/betting-calculators/vig


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Quote: roudy12345

Let's say the favorite in a baseball game is -170 & the underdog is +145. I used to think that the vig free odds would be right in the middle. (-157.5) (+157.5). My math is showing that this is not correct. I'm seeing that the favorite would be a higher minus number while the underdog would go up more than the half way point. If the favorite is -170, what would the juice free line be? What would the +145 line be if it were actually juice free?

For example if two teams are both -110 to win. -100 is juice free.

Could you explain how you came up with the number so I could translate other odds to juice free?

Another thing, do casino edges go up with higher numbers? Such as -110 -110 seems to be a 4.54% house edge. Is the edge the same on a -170 +140? Or does the house edge go up when there's a bigger favorite? Say a game has the favorite as -550 & +425. Is this a worse bet than -110 -110?
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Yeah 157.5 isn’t the “right” way to do it. You should convert the odds into probabilities, then add the probabilities up. It will total to more than 100%. Then divide the probabilities by the sum, so that the probabilities are reduced to adding to 100%. Those are now vig free probabilities that can be converted back to big free odds.

-170 and +145 then become about +/- 154 on a vig free basis.

Note that I’m not sure this way is “right” either, but it’s the commonly used method. It assumes there’s more “vig” in the favorite than in the dog because it reduces the probabilities proportionately.

I could argue that another way is to assume the same total amount of vig in both the favorite and the dog. If that’s right then -170 and +145 become +/- 166.5.

just type "no vig calculator" or "sportsbook vig calculator" into a search bar and get all the answers. With a -170 favorite and 145 underdog, 154 is the price where the sportsbook has an equal vig on both sides. In this case 3.78%.

But just like betting the field in craps compared to passline, the sportsbook does not put an equal vig on all bets. I would say the no-vig price is most likely somewhere between 145 and 170. If it wasn't, I would have already made a bet to move the line; or it's something I can't bet it and even if one of the sides has a negative house edge, it isn't really meaningful to me. If the favorite was -160 earlier in the day, that means the bettors believed the no-vig price was over 160 and it means the sportsbook doesn't want to take anymore bets on the favorite at that price. Based only on that information, I would put the no-vig price closer to 170 than 145.

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the house edge does change as odds start to get a lot longer. A favorite priced at 600-to-1 or more might not have any house edge (eg the field to win the next major against Tiger Woods). Even if we are certain of the outcome, the worst the sportsbook can do is lose 0.17%. But if someone is betting Tiger against the field at 25-to-1, they're losing 100%, not 4%, despite the calculator telling us the hold percentage is only 3.68%. So they can put him up at 250-to-1 and still be fine despite the calculator telling us the hold is less than the excise tax. If it's something less certain, like Paolo Banchero to be the #1 pick, they have a chance to get crushed putting up long odds, so usually when we see those odds, most of the vig will be on the longshot as a way to protect themselves.

Quote: TomG

just type "no vig calculator" or "sportsbook vig calculator" into a search bar and get all the answers. With a -170 favorite and 145 underdog, 154 is the price where the sportsbook has an equal vig on both sides. In this case 3.78%.

But just like betting the field in craps compared to passline, the sportsbook does not put an equal vig on all bets. I would say the no-vig price is most likely somewhere between 145 and 170. If it wasn't, I would have already made a bet to move the line; or it's something I can't bet it and even if one of the sides has a negative house edge, it isn't really meaningful to me. If the favorite was -160 earlier in the day, that means the bettors believed the no-vig price was over 160 and it means the sportsbook doesn't want to take anymore bets on the favorite at that price. Based only on that information, I would put the no-vig price closer to 170 than 145.

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the house edge does change as odds start to get a lot longer. A favorite priced at 600-to-1 or more might not have any house edge (eg the field to win the next major against Tiger Woods). Even if we are certain of the outcome, the worst the sportsbook can do is lose 0.17%. But if someone is betting Tiger against the field at 25-to-1, they're losing 100%, not 4%, despite the calculator telling us the hold percentage is only 3.68%. So they can put him up at 250-to-1 and still be fine despite the calculator telling us the hold is less than the excise tax. If it's something less certain, like Paolo Banchero to be the #1 pick, they have a chance to get crushed putting up long odds, so usually when we see those odds, most of the vig will be on the longshot as a way to protect themselves.
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I am not understanding your explanation. You cannot know what the vigorish is without knowing what the true odds are and what amounts are bet on the different outcomes. This is fundamentally different than craps where you know the true odds and it does not matter how much is bet on any outcome. Each craps bet has a calculable house edge. How are we supposed to calculate what the vig is on Tiger against the field at 25-to-1 or 250-1?

Lets say that a sports book puts up a line today on the 2024 superbowl winner. Unless bettors are totally clueless, they will only bet on the Chiefs. Even if the line is -1000000 on the Chiefs, there is a negative house edge. You can argue that the vig on the 49ers is 100% no matter the line, but if nobody bets on the 49ers, that vig is meaningless. It results in no profit to the book and does not offset the negative vig on the other side. So even if we know the true probability is 100% Chiefs, the book cannot force the longshot bettors to pay the vig.

The book has to collect the vig from bettors on the heavy favorite. That is where the money is. In a parimutuel pool, most of the takeout comes from folks betting on the chalk. This is built into the parimutuel odds. Why would a book operate any differently?

Fixed odds are different than pari-mutual. Sportsbooks would love to operate them the same way. Bettors would revolt.

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sportsbooks cannot know the true odds - the lines put up are their best estimate with shading to make the fave a worse bet because the fave will be slightly overbet - and they are then moved according to the betting - always shaded so bets on the fave lose slightly more in the long run
that is why some bettors can profit - their estimate is better than the sportsbooks - and/or the public's when the lines are bet down
most winning bettors can only do this on a very few games
studies of parimutuel wagering at the track have shown that the crowd is very accurate in the long run in estimating the odds
no doubt the same is true of sports betting even though the house operates differently from parimutuel wagering

the Wiz has a page for each of the major sports

here is an example from his MLB page - he has tracked thousands of bets

probability re the over/under bets:

over wins - 46.97%__________under wins - 48.14%____________HE on over - 5.45% (over is basically the favorite) - HE on under - 3.20%

nobody is going to be able to beat lines like that very often

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https://wizardofodds.com/games/sports-betting/mlb/

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