adjust pre-post

[garyf]

Was thinking of looking at bhagwans plan of backing
horses that open or start shorter than their p/post.

The problem i found that the on course bookies adjust
up for scratchings the p/post stays the same.

In instances say where the 1st-2nd p/post are
scratched the 3rd-4th-5th p/post will always be longer
than the opening fav's so thus always qualifying.

As an example will look at sandown race=1 today.

I will use the A.A.P prepost as i have daily access to them.

Before scr the p/post was like this

1=5.0 (4/1) 20%
2=4.0 (3/1) 25%
3=2.5(6/4) 40%
4=15.0(14/1) 6.67%
5=3.5(5/2) 28.57%
6-21.0 (20/1) 4.76%

Adding these up the total market %=125%
nos 1+5 are scratched .
Their market %'s total 48.57 (20%+ 28.57%)

We therefore have to deduct these %'s from the
total market % to get a new table.

125%-48.57%=76.43%

Then divide 125% by 76.43=(1.635) (this is the new table).

All that's required now is to multiply the
horses that are left %'s x the new table.

2=25%x1.635=40.87%=(6/4)(2.5)
3=40%x 1.635=65.4%=(8/15)(1.45)
4=6.67%x1.635=10.9=(8/1)(9.0)
6=4.76%x1.635=7.78=(12/1)(13.0)

To check if these calculations are correct just
add up the new %'s they should be close to 125%

(40.87)+(65.4)(+10.9)(+7.78) = 124.95.

This then would give you a more accurate guide
using bhagwans shorteners method.

I realize most know how to do this anyway but
for those who are unsure this would be a better guide.

Problem is doing this on all the races manually would mean
the meetings would be over before you finished.

Maybe a program could be written up
by one of our resident computer experts ???.

The on course opening prices for the race was this.

2=(-2.1-2.5)
3=((1.6-1.7)
4=(15-17-14)
6=(20-21).

This brings us more in line with the on course prices
adjusted up rather then leaving them as is.

Cheers
garyf.

[Dennis G]

Hey garyf,
I posted an Excel SS sometime ago to do exactly that. If you are interested the URL is http://forums.ozmium.com.au/showthread.php?t=18718

Den

[Bhagwan]

There is a market re-framing program to be had at Ozracetools.

[Bhagwan]

Using that free Market Re-Framer
One can set the New Market Value box, at the top, to the required percentage & go from there.

You will notice that most newspaper & online pre-post markets are set around 125-136% before scratchings .
This is done to allow for possible scratchings of the longer priced runners, which is common to see.
Not so good if the first 2 Favs are scratched .

That Market Re-Framer is a handy bit of kit, for this exercise .
Its very well laid out & user friendly.
There are some other handy free punting tools there as well.

[garyf]

Thanks dennis g and bhagwan.

There exactly what i need.

Cheers
garyf.

[Mark]

garyf, this might be of interest to you.

http://www.propun.com.au/racing_forums/showthread.php?t=18705&page=1&pp=10&highlight=opening+price

[garyf]

Interesting read that mark.

Wonder if shaun is reading this
he could let us know how it's going.

With my own betting and ratings each
day i was looking for a new idea to improve s/rate.

Guess it will come down to an accurate p/post.

A.A.P. appear to be as good as any.

Now comes the long laborius task of
going back through the dynamic website
and adjusting up for scratchings.

Have a feeling it could be worthwhile
betting on the type of races i do.

This is something new without tinkering
with the ratings which i have just about exhausted.

Thanks again.

Cheers
Garyf.

[garyf]

Forget the part concerning shaun re my last post(sorry mate)

Was reading another thread while posting.