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SHAPESHIFTER
06 Feb 15 13:05
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Date Joined: 04 Apr 03
| Topic/replies: 3,194 | Blogger: SHAPESHIFTER's blog
Posting a question here that is going on in another forum but wondering about views:

The usual discussions of ROI came up and someone posted theirs but took away bets where there had been a push (i.e. "draw no bet")

Besides the basic argument that ROI is only when you have a few bets a week as opposed to several a day, it was interesting to see people looking over their last 50 bets then including or excluding 'push' bets.

I took it one step further where asian handicap bets actually can include a 'push' which sent people back to their spreadsheets.

My view: If someone puts down 20 bets, for simplicity

all bets were 2.00 odds
all were Draw no bet

8 winners = 8 profit
5 losser= -5
7 push = 0

View 1) Don't include push (mainly americans, btw)
so you have:
3 net points divided by 13 = 23% ROI
General view is it is the same as a 'nulled bet' which, in my view, didn't make sense since it could have won or lost.

View 2) Include push
3 divided by 20 = 15%

I'll post my own view and reasons later.  Curious where other people lie on this.

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Replies: 16
By:
Latalomne
When: 06 Feb 15 13:18
Not something I've ever considered as it's not relevant to the way I bet, but your position makes most sense to me.  You can't treat an event where you had an exposure like it was a non-runner in a horse race.
By:
JML
When: 06 Feb 15 15:32
Agreed, 15% Roi.
By:
dave1357
When: 06 Feb 15 20:44
Its called return on investment

Q What did you invest?  A 20 units

Q What was your return? A 23 units

Its not called return on investment except when there is a push and I'll pretend I didn't make a bet.
By:
dave1357
When: 06 Feb 15 21:10
Also the push odds may make it a positive (or negative) outcome for you.

Imagine a (vig free) bet that the book thinks is 2-1 A to win, 2-1 B to win and 2-1 the push. 

You know the actual odds are 6/4 A to win, 4-1 B to win and 6/4 the push.

So 20 bets and you get 8 wins, 8 pushes and 4 losses. 

ROI is 20% conventionally AND mathematically. 

The other way ROI is 33% which is much higher than mathematical and if you, for example, use kelly staking, would lead you to grossly overstake.
By:
SHAPESHIFTER
When: 09 Feb 15 14:32
The reason I posted this is that looking at several system players around, they seem to 'justify' following certain systems that have several push scenarios.

So it reads to me that to justify following it, making the return worthwhile, they need to remove the push from the equation.

In general, if you have the push factored in and you have a decent ROI, you're doing okay.
By:
Baz
When: 09 Feb 15 20:16
If you are to remove the push, would you remove from your records a £100 E/W bet @ 5/1 1/5 odds that placed and ret'd £200?
Naturally if you're a winning player/tipster you want to remove any flat returns but doing so reduces potential downside (in terms of overall stakes - if overall stakes are far higher, unit stakes might need to be lower for people following)& increases ROI without good reason.
By:
SHAPESHIFTER
When: 09 Feb 15 22:29
I'm going through a whole 'analysis' of betting right now.  ROI is one of the numbers that I am reassessing its value.

But with "systems" or people using data, it is pretty key to deciding where you are finding an edge or waisting your time following certain approaches.

The push would be part of it and, as Baz said, a push is essentially the same as an EW.
By:
TheInvestor2
When: 20 Feb 15 22:41
dave1357 06 Feb 15 20:44 Joined: 05 Sep 10 | Topic/replies: 3,087 | Blogger: dave1357's blog
Its called return on investment

Q What did you invest?  A 20 units

Q What was your return? A 23 units

Its not called return on investment except when there is a push and I'll pretend I didn't make a bet.
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dave1357
dave1357 06 Feb 15 21:10 Joined: 05 Sep 10 | Topic/replies: 3,087 | Blogger: dave1357's blog
Also the push odds may make it a positive (or negative) outcome for you.

Imagine a (vig free) bet that the book thinks is 2-1 A to win, 2-1 B to win and 2-1 the push. 

You know the actual odds are 6/4 A to win, 4-1 B to win and 6/4 the push.

So 20 bets and you get 8 wins, 8 pushes and 4 losses. 

ROI is 20% conventionally AND mathematically. 

The other way ROI is 33% which is much higher than mathematical and if you, for example, use kelly staking, would lead you to grossly overstake.


You could say exactly the same thing about voided bets. if you include these, you have to include them in your analysis as well for the sake of consistency.

For the purposes of Kelly, you'd have to factor in the probability of a push, but you would also have to factor in the probability of a void bet.

The convention is not to count them. If Betfair charged a commission per transaction rather than per winning market, they would not charge for a DRAW NO BET bet when it's a draw. The clue is in the name of the market Silly
By:
JML
When: 20 Feb 15 23:27
Blackjack is a draw no bet game and every book I've read
counted them as bets when calculating the % for different
strategies.
By:
CLYDEBANK29
When: 20 Feb 15 23:27
"Imagine a (vig free) bet that the book thinks is 2-1 A to win, 2-1 B to win and 2-1 the push. 

You know the actual odds are 6/4 A to win, 4-1 B to win and 6/4 the push."

.............

There are 2 ways you could look at that. 

1.  Is that there is a 40% chance you win and a 20% chance you lose.  You are twice as likely to win as to lose on events priced equally.  It's effectively like getting evens on a 1/2 shot.

2.  Separate each bet into 2 bets. 
Bet one is you are getting 2/1 on a 6/4 shot and
Bet two is you are getting 1/2 on a 1/4 shot.   

In 1 the effective ROI is 33.3%

In 2 the ROI return on bet one is 20% and the return on bet two is 20%, but bet 2 is clearly better than bet one.  Flip both bets so you are getting 4/1 on a 2/1 and 4/6 on a 1/2 shot and you are getting ROIs of 66.7% and 11.1%

I don't know how ROI, which is a business return on capital, relates to gambling in a conventional sense.  I think in terms of relevance its deeply flawed.
By:
CLYDEBANK29
When: 20 Feb 15 23:55
The Pinnacle Sports algorithm works on the basis that you can win or stake £100, so if the max bet is £100 you can stake £400 on a 1/4 shot or £100 on a 4/1 shot.  If you bet with many bookies the limit is often to win £100 regardless of odds.

So looking at the 1/2 on a 1/4 shot with a ROI of 20% in a conventional sense.
With Pinny you can have £200 to win £100.  With Skyebet you can have £200 to win £100

Flipping the bet so you get 4/1 on a 2/1 shot with a 67% return.
With Pinny you can get £100 on to win £400.  With Skyebet you can have £25 ton win £100

I think effectively in terms of value both bets are in pure gambling terms the equal of each other regardless of the different ROIs so ROI in a conventional sense is absurd to begin with without factoring in inverse relationships somehow.

However with Pinny and Skyebet after 10 bets on the 1/2 shot you have cleared £400 on average

After 10 bets on the 4/1 shot with Pinny you are £667 up on average, with Skyebet you are £167 up on average.

You could argue whether the ROIs are 67% and 20% or whether they are effectively the same.  But because of practicalities the ROI figure becomes even more irrelevant.
By:
CLYDEBANK29
When: 21 Feb 15 00:07
I don't know how bookies look at accounts but if they look at percentage returns on stakes as a ROI measure with a view to restricting, it's a much better strategy to back good value short prices than good value big priced outcomes.
By:
dave1357
When: 21 Feb 15 09:44
You could say exactly the same thing about voided bets. if you include these, you have to include them in your analysis as well for the sake of consistency.

For the purposes of Kelly, you'd have to factor in the probability of a push, but you would also have to factor in the probability of a void bet.

The convention is not to count them. If Betfair charged a commission per transaction rather than per winning market, they would not charge for a DRAW NO BET bet when it's a draw. The clue is in the name of the market


Fair point, but I would imagine that void bets are a fairly rare occurrence, but draws in DNB are relatively frequent.  So ignoring the former wouldn't overstate ROI by so much as the ignoring the latter.
By:
TheInvestor2
When: 21 Feb 15 17:29

CLYDEBANK29 21 Feb 15 00:07 Joined: 10 Jan 02 | Topic/replies: 5,224 | Blogger: CLYDEBANK29's blog
I don't know how bookies look at accounts but if they look at percentage returns on stakes as a ROI measure with a view to restricting, it's a much better strategy to back good value short prices than good value big priced outcomes.


That's exactly right, it is a better strategy.
By:
SHAPESHIFTER
When: 01 Mar 15 22:21
Came across someone else discussing it.....
http://green-all-over.blogspot.co.uk/2015/03/yields-down-when-push-comes-to-void.html
By:
cpfc4me
When: 01 Mar 15 22:37
That guy's good! Knows his stuff :)
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