Drifter/Steamer statistics

The sport of kings.
Post Reply
User avatar
ruthlessimon
Posts: 2094
Joined: Wed Mar 23, 2016 3:54 pm

Euler wrote:
Mon May 07, 2018 2:04 pm
Backing a drifter doesn't make much sense to me as a price can drift for many reasons. But laying a steamer does.
It makes sense doesn't it, except on my pre-off data - laying a drifting fav sucks massively (exit @ 0mins).

April:
Image

May (so far):
Image

Interesting that the start of both months saw a blind lay strategy doing well(ish). & then both pretty much down the same amount as the previous
User avatar
Euler
Posts: 24700
Joined: Wed Nov 10, 2010 1:39 pm
Location: Bet Angel HQ

WAP is always going to be skewed heavily to the last couple of minutes as that is when most of the money arrives. So I'd imagine a variance related to that is a little skewed also?
User avatar
northbound
Posts: 737
Joined: Mon Mar 20, 2017 11:22 pm

ruthlessimon wrote:
Mon May 07, 2018 2:26 pm
northbound wrote:
Mon May 07, 2018 2:18 pm
ruthlessimon wrote:
Mon May 07, 2018 2:17 pm
Was the sample size of trades for both strategies meaningful?
All UK / IRE races from Oct 2017 until Apr 2018.

I don't have snapshots prior to that.
It's just that on my data a 20% drift is extremely rare; let alone from the WAP, which would have formed very late!
20% drift on a 6.00 - 20.00 horse doesn't look so uncommon in my data.

I'm talking about snapshots taken at scheduled start, so perhaps the data at the actual off is a bit tighter as more money arrived in the next few minutes of a late race, thus reducing the gap between WAP and BB.

Here are a few random horses from my sample:

2018-03-20 Newcastle Velvet Vision WAP 5.39 / BB 7.60 41%
2017-12-27 Wolverhampton Jumping Around WAP 15.22 / BB 18.50 21%
2017-10-20 Redcar Essential WAP 13.11 / BB 16.5 25%
User avatar
ruthlessimon
Posts: 2094
Joined: Wed Mar 23, 2016 3:54 pm

northbound wrote:
Mon May 07, 2018 2:37 pm
2018-03-20 Newcastle Velvet Vision WAP 5.39 / BB 7.60 41%
I'd calculate that as a 5% drift, not 40%!
User avatar
northbound
Posts: 737
Joined: Mon Mar 20, 2017 11:22 pm

ruthlessimon wrote:
Mon May 07, 2018 2:39 pm
northbound wrote:
Mon May 07, 2018 2:37 pm
2018-03-20 Newcastle Velvet Vision WAP 5.39 / BB 7.60 41%
I'd calculate that as a 5% drift, not 40%!
BB 7.60 / WAP 5.39 = 1.41

BB is 41% bigger than WAP in my mind :)
User avatar
ruthlessimon
Posts: 2094
Joined: Wed Mar 23, 2016 3:54 pm

northbound wrote:
Mon May 07, 2018 2:41 pm
BB is 41% bigger than WAP in my mind :)
I must say I've never done it like that before ;)

Be interesting if Peter agrees with that method
User avatar
northbound
Posts: 737
Joined: Mon Mar 20, 2017 11:22 pm

ruthlessimon wrote:
Mon May 07, 2018 2:32 pm
Euler wrote:
Mon May 07, 2018 2:04 pm
Backing a drifter doesn't make much sense to me as a price can drift for many reasons. But laying a steamer does.
It makes sense doesn't it, except on my pre-off data - laying a drifting fav sucks massively (exit @ 0mins).
Si, Euler mentioned laying a STEAMER, not a drifter.

In any case, my data shows that laying a drifting fav works reasonably well in certain conditions. Not going to elaborate here, for obvious reasons, but happy to discuss in private. 8-)
User avatar
ruthlessimon
Posts: 2094
Joined: Wed Mar 23, 2016 3:54 pm

northbound wrote:
Mon May 07, 2018 2:44 pm
Si, Euler mentioned laying a STEAMER, not a drifter.

In any case, my data shows that laying a drifting fav works reasonably well in certain conditions. Not going to elaborate here, for obvious reasons, but happy to discuss in private. 8-)
I know but this - "Backing a drifter doesn't make much sense" - can also be read in a pre-off sense; & I'm in the process of trying to work out whether it stacks up in my own data
User avatar
gstar1975
Posts: 615
Joined: Thu Nov 24, 2011 11:59 am

ruthlessimon wrote:
Mon May 07, 2018 2:43 pm
northbound wrote:
Mon May 07, 2018 2:41 pm
BB is 41% bigger than WAP in my mind :)
I must say I've never done it like that before ;)

Be interesting if Peter agrees with that method
Can anyone clear up this method of working out the % drift/steam. I have always taken of a 1 from each value then divided. Everyone seems to have a different way of calculating.

If you take the Betfair price at say 11am is 6.4 and it drifted to 8.4 so 7.4/5.4= 1.37 so the move is 37% or is it 8.4/6.4=1.31 which is saying a 31% move???

But when you take off 37% from 8.4 so 7.4 * ((100-37=63) so use 0.63)). 7.4*0.63 = 4.66 +1 = 5.66

Its very confusing can Euler please clear this up once and for all? And I'm not talking about % move in Implied odds either, I want a % move from the actual Price not imlplied odds.

Very much appreciated.
User avatar
MemphisFlash
Posts: 2126
Joined: Fri May 16, 2014 10:12 pm
Location: Leicester

the way i would look at this would be from your example:-
the difference between you start figure of 6.4 and the drift to 8.4 = 2.
2/8.4 = .23809 so to me the drift is 23.81% and not the figure you have of 37%
LinusP
Posts: 1871
Joined: Mon Jul 02, 2012 10:45 pm

MemphisFlash wrote:
Sun Nov 25, 2018 6:26 pm
the way i would look at this would be from your example:-
the difference between you start figure of 6.4 and the drift to 8.4 = 2.
2/8.4 = .23809 so to me the drift is 23.81% and not the figure you have of 37%
That’s a very odd way of calculating this, basically makes it impossible to compare as you go up/down the odds. If it was 50 -> 100 you would get a 200% drift and 1.5 -> 2.0 is 25%...

6.4 - 8.2 is a percentage point difference (chance) of 3.4%, I strongly recommend using percentage point differences.
Post Reply

Return to “Trading Horse racing”