[FreeFall]

I'm sure I'm missing something, but lets say that the closing line for a RL is +110. If I'm doing a 6 game chase of this RL that has 47% chance to win, the odds of all 6 failing at


100-47 = .53 ^ 6 = 2.216%

lets same my unit size if $10.

GM1: 9.09 / 10.00
GM2: 17.35 / 19.09
GM3: 33.13 / 36.44
GM4: 63.25 / 69.57
GM5: 120.75 / 132.82
GM6: 230.52 / 253.57

so when we lose a chased bet we lose $474.09

since we'll lose 2% of our bets we win 98 and lose 2. so we win $980 and lose $948.18 leaving us with $31.82.

Where is my math wrong?

[MonkeyF0cker]

Because you are committed to it at ANY price...

[Justin7]

If you played a team at +110 take back -120, the middle price is -115. You will lose 53.5% of the time.

On any chase, you now lose 2.34% of your chases. That extra fractional percent guarantees you'll lose long term.

Chase systems are a sham. If the bet is +EV, you don't need brain donor money management to win with it. If the bet is -EV, no hocus pocus will help it.

[FreeFall]

Because you are committed to it at ANY price...

I took the time to prove my thoughts with math, I'd like the same. Assuming my odds are +110 EVERYTIME am I right? My avg odds have been ~+125, but I'm trying to find worst case and either way don't see it.

[LT Profits]

I'm sure I'm missing something, but lets say that the closing line for a RL is +110. If I'm doing a 6 game chase of this RL that has 47% chance to win, the odds of all 6 failing at


100-47 = .53 ^ 6 = 2.216%

lets same my unit size if $10.

GM1: 9.09 / 10.00
GM2: 17.35 / 19.09
GM3: 33.13 / 36.44
GM4: 63.25 / 69.57
GM5: 120.75 / 132.82
GM6: 230.52 / 253.57

so when we lose a chased bet we lose $474.09

since we'll lose 2% of our bets we win 98 and lose 2. so we win $980 and lose $948.18 leaving us with $31.82.

Where is my math wrong?

You went wrong by rounding the percentage of losses. Using your rate of 2,216%, in the long run, you would NOT go 98-2 every 100 games, but rather 97.784-2.216. That changes things dramatically:

97.784 * 10 = 977.84
2.216 * 474.09 = 1050.58
-------------------------
Net LOSS = (72.74)
===================

[FreeFall]

If you played a team at +110 take back -120, the middle price is -115. You will lose 53.5% of the time.

On any chase, you now lose 2.34% of your chases. That extra fractional percent guarantees you'll lose long term.

Chase systems are a sham. If the bet is +EV, you don't need brain donor money management to win with it. If the bet is -EV, no hocus pocus will help it.

I don't understand your middle price and I believe my +110 to be the middle price. I was following someones "system" and they always get +110 for the RL@bodog where I could get +135 @ matchy, maybe I'm missing your terms.

[LT Profits]

I don't understand your middle price and I believe my +110 to be the middle price. I was following someones "system" and they always get +110 for the RL@bodog where I could get +135 @ matchy, maybe I'm missing your terms.

By "middle price", Justin means the No Vig line. So a lineset of -120/+110 has a No Vig Line of approximately -115 (it is actually -114.5, but I digress...lol).

A -115 would have a win expectancy of 53.488%, making the odds of not hitting a 6-game chase 2.341%.

[MonkeyF0cker]

He's referring to the zero-vig probability of the line set. As Justin and LT pointed out, there are two substantial errors in your calculations. First, you need to find the implied probability of the line. If you're betting a +110 into a 10 cent line (+110/-120), your no-vig line is +114.55. If it's a 20 cent line (+110/-130), your no-vig line is +118.70. See http://www.sportsbookreview.com/forum/handicappe...rcentages.html for instructions on how to calculate it. Now if we convert to win percentages and round 2 decimal places (merely because I'm not at home and am using the betting tools on SBR as a shortcut), we get win probabilities of 46.61% and 45.72%, for 10 cent lines and 20 cent lines respectively. The probability of losing six bets in a row is 2.3161% (10 cent) and 2.5576% (20 cent). This yields a loss of $121.20 for 10 cent lines and a loss of $238.11 for 20 cent lines.

Hope that helps. Also note that assuming +110 every game is fairly arbitrary. You are committed to chase even if you're getting -120 or worse (just as arbitrary.. I know).

[FreeFall]

You guys are awesome! Thanks for the help.

Does it change if say I have +135 odds? So I win the same, but lose less? Or does the vig in the line make sure to protect that.

[xyz]

No, it doesn't change with +135 odds, or any other odds when your price is worst than the no vig line. Understanding the posts in this thread will save you a lot of money.

[MonkeyF0cker]

The calculations here are fairly useless other than to exemplify the fact that multiple -EV wagers does not create an +EV scenario. No other arbitrary numbers will make a difference. Unless your wagers are +EV to begin with, there is no contorting them into +EV wagers afterward.

[u21c3f6]

You guys are awesome! Thanks for the help.

Does it change if say I have +135 odds? So I win the same, but lose less? Or does the vig in the line make sure to protect that.

I'm not sure what you mean by win the same. If you mean that you get +135 and still hit at 47%, then that is +EV to begin with and will be very profitable as long as one does not overbet.

As others have stated, if your wagers are -EV, there is no system of wagering that will make them +EV. You may show a profit for a while but the averages will catch up with you the longer you play.

Joe.

[u21c3f6]

The calculations here are fairly useless other than to exemplify the fact that multiple -EV wagers does not create an +EV scenario. No other arbitrary numbers will make a difference. Unless your wagers are +EV to begin with, there is no contorting them into +EV wagers afterward.

While I agree with the concept of what you wrote, let me share with you a slight twist. I for the most part only wager on events that offer live wagering. Prior to the event, I make a wager but I have no idea if the wager is + or -EV. I of course try to get the very best price but that price is based on how the game will end, not how it gets there. By wagering on the game live, I turn that initial pre-game wager into part of a +EV hedge even though my initial pre-game wager may have been -EV based on how the game will end. Hope that made sense.

Joe.

[xyz]

Hi Joe,
Based on your previous writings on live wagering, I know you know what you are doing. But I disagree that taking a pre-game wager without knowing if it is + or -EV is helping you to be more profitable in the long run. I think you would do better just not take any pre-game wager. I believe your edge is during live wagering when you know the true odds better than other players.

While I agree with the concept of what you wrote, let me share with you a slight twist. I for the most part only wager on events that offer live wagering. Prior to the event, I make a wager but I have no idea if the wager is + or -EV. I of course try to get the very best price but that price is based on how the game will end, not how it gets there. By wagering on the game live, I turn that initial pre-game wager into part of a +EV hedge even though my initial pre-game wager may have been -EV based on how the game will end. Hope that made sense.

Joe.

[u21c3f6]

Hi Joe,
Based on your previous writings on live wagering, I know you know what you are doing. But I disagree that taking a pre-game wager without knowing if it is + or -EV is helping you to be more profitable in the long run. I think you would do better just not take any pre-game wager. I believe your edge is during live wagering when you know the true odds better than other players.

Frankly, I can't answer that because I never looked at it that way. In fact, there is a good chance that my second (hedge) wager could also be -EV on its own based on how the game ends.

Let me explain. Lakers at home, -4 favorite tied at halftime are offered at +140. Now I assume that is probably -EV based on how the game ends. But here is how I look at it. The Lakers are a good third quarter team. Favored at home they have a greater expectation of taking the lead at the start of the third quarter and I would actually put it at about 2/3 chance. Each situation has its own %'s. In this case the amount that the odds would go up or down are approximately the same dependent upon which team takes the early lead. If the other team takes the early lead, then I might have to hedge at -180 to -200 for a guaranteed loss. However if the Lakers take the early lead, then I will probably be able to hedge at +100 to +120 for a guaranteed win. The point is that I also assume that the hedge bet is -EV based on how the game ends but that doesn't matter when you hedge as I described. My guaranteed loss in this situation would range from .14 to .20 on the dollar while my guaranteed win would range from .20 to .31 on the dollar. Even if its a 50-50 chance who will take the lead there is still a profit but in this type of situation I will win almost twice as many times as I will lose for an even greater profit overall.

Even if my second (hedge) wager was a true +EV wager, I would still hedge as it provides other advantages. First, it allows for a greater win % and second, because I know I am going to hedge, I am able to wager a much larger % of my bankroll as the initial wager. It has been my experience that both of these reasons help to create a smoother more consistent zig-zag increase in my bankroll than making let-it-ride wagers. I very rarely make let-it-ride sports wagers anymore.

Joe.

[billdo75]

I do have a question about all of this, as I believe it's my chase thread that started this...

Let's say we're doing a 4-game chase, chasing $30 at +110 odds each game. Let's say the line in question is a 20 cent line, making the true, no-vig line for our bet +118.70. That equates to an expected win percentage of 45.73%. Proceeding through the chase, we have:

Game 1, $27.27 to win $30.00, +$30.00 @ 45.73%, -$27.07 @ 54.27% -> -$1.08
Game 2, $52.07 to win $57.27, +$30.00 @ 70.55%, -$79.34 @ 29.45% -> -$2.20
Game 3, $99.40 to win $109.34, +$30.00 @ 84.02%, -$178.74 @ 15.98% -> -$3.36
Game 4, $178.74 to win $189.76, +$30.00 @ 91.33%, -$368.50 @ 8.67% -> -$4.57

Each leg of that is -EV. Even at +135 odds, it's still the same. The final number is different, but it's still in the red. However, I adopted a different strategy shortly after starting that system. I didn't like the idea of a 4-game chase only netting the original amount. It seemed like winning the bet once and taking 3 days off. Of course, it doesn't seem that way when your balance keeps dipping each day further into the chase you go Because it's a chase, you can't afford to get real crazy, but I started incrementing my to-win amount each day the chase goes on (30-40-50-60). When I crunch those numbers using the same methodology above, it ends up being +EV after the first game of the chase:

Game 1, $27.27 to win $30.00, +$30.00 @ 45.73%, -$27.27 @ 54.27% -> -$1.08
Game 2, $61.16 to win $67.27, +$40.00 @ 70.55%, -$88.43 @ 29.45% -> +$2.17
Game 3, $125.85 to win $138.43, +$50.00 @ 84.02%, -$214.27 @ 15.98% -> +$7.76
Game 4, $249.34 to win $274.27, +$60.00 @ 91.33%, -$463.62 @ 8.67% -> +$14.58

Is that correct or am I doing something wrong...besides chasing to begin with? I love the Think Tank...always learning something new. Thanks, fellas!

[xyz]

It can't be +EV. Please do the following calculation:

P(win game 1)*30 + P(lose game 1 then win game 2)*40 + P(lose game 1, lose game 2, then win game 3)*50 + P(lose game 1, 2, 3, then win game 4)*60 - P(lose all 4 games)*463.62

P(A) is the probability of event A happening. Check that number, and it should be negative, otherwise your math is wrong.

[u21c3f6]

billdo75, I'm not sure how you are calculating your %'s. I get -$5.45 as follows (numbers rounded):

Hit Game 1 .4573 @ $30 = $13.72
Hit Game 2 .2482 @ $40 = $ 9.93
Hit Game 3 .1347 @ $50 = $ 6.73
Hit Game 4 .0731 @ $60 = $ 4.39
Miss All 4 .0867 @ -$463.62 = -$40.22 for a total expectation of -$5.45

Joe.

[billdo75]

It can't be +EV. Please do the following calculation:

P(win game 1)*30 + P(lose game 1 then win game 2)*40 + P(lose game 1, lose game 2, then win game 3)*50 + P(lose game 1, 2, 3, then win game 4)*60 - P(lose all 4 games)*463.62

P(A) is the probability of event A happening. Check that number, and it should be negative, otherwise your math is wrong.

billdo75, I'm not sure how you are calculating your %'s. I get -$5.45 as follows (numbers rounded):

Hit Game 1 .4573 @ $30 = $13.72
Hit Game 2 .2482 @ $40 = $ 9.93
Hit Game 3 .1347 @ $50 = $ 6.73
Hit Game 4 .0731 @ $60 = $ 4.39
Miss All 4 .0867 @ -$463.62 = -$40.22 for a total expectation of -$5.45

Joe.

I was wondering why just throwing more money at it would make it +EV. Now I see that fudging the numbers does the trick nicely Thank you for the correction and for showing your work so I know what I did wrong.

[Number Freak]

Chase systems are a sham. If the bet is +EV, you don't need brain donor money management to win with it. If the bet is -EV, no hocus pocus will help it.

But a chase style can extrapolate more profit from +EV wagers, no?

For example, you identify a +EV matchup in a 3-game baseball series (say .692 in individual games at an average lay of -157). You play the desired team up to three games until they win. Say 55 series' worth of data yields the following results:

Game 1 = 37-18
Game 2 = 13-5
Game 3 = 4-1

At $100 units, flat-betting the 54-24 individually would require wagering $12,246 and net you $1,632 for an ROI of 13.33%.

Chasing exactly one unit would require $21,082.82 and net you $3,802.51 for an ROI of 18.04%.

That's assuming every wager at -157. The sole chase loss could be more or less than the $1,597.49 in the example.

[Rich Boy]

If you have a +EV wager, Kelly wagering is the optimal strategy for bankroll growth.