Hello

[Bhut]

Been using gruss now for about 20 days.

been messing around with the trial period. Very good forum load of answers but they create so many more questions.

Anyway the fact that you can hedge up with gruss makes my life simple but i was after a formula for excel that does this for me.

i.e I have layed the draw at 3 for £2 to make a 10% of my stake, what would the odds need to be and how much would I have to stake?

Hope that makes sense, it does in my brain!

Cheers

Ian

[osknows]

Hello,

To hedge for 10% of your LAY stake you need
BACK Odds = 3/0.9 = 3.33
BACK Stake = £2*0.9 = £1.80

This doesn't include commission. If you need the maths let me know

[osknows]

The hedge of 10% is probably not exact for possibly 2 reasons
1. Odds of 3.333333 are rounded to 3.3 or 3.35 on Betfair
2. The commission probably will take off a certain amount from the final value


As requested, here is the maths

Sl = LAY Stake
Ol = LAY Odds
Sb = BACK Stake
Ob = BACK Odds

C = Commission % (use value between 0 - 1)
P = Profit % of LAY Stake (use value between 0 - 1)


Without Commission
==================

If you enter a position on the LAY side then
If selection Wins: Profit = -Sl(Ol-1)
If selection Loses: Profit = +Sl

If you enter a position on the BACK side then
If selection Wins: Profit = +Sb(Ob-1)
If selection Loses: Profit = -Sb

You want to find Sb and Ob so that Profit across both win and lose = PSl (P% of your LAY stake)

If selection Wins then:
-SlOl+Sl+SbOb-Sb = PSl (Eq.1)

If selection loses then:
Sl-Sb = PSl (Eq.2)

Rearrange Eq.2:
Sb=(1-P)Sl (Eq.2a)

Substitute Eq.2a into Eq.1:
-SlOl+Sl+(1-P)SlOb-(1-P)Sl = PSl (Eq.3)

Cancelling terms in Eq.3 gives:
Ob = Ol/(1-P) (Eq.3a)

Using your example you have Sl, Ol and P and you want to find Sb & Ob
Sl = £2
Ol = 3
P = 0.1 (10% of LAY stake)

Eq.2a Sb = (1-0.1)*2 = £1.80
Eq.3a Ob = 3/(1-0.1) = 3.333


With Commission
===============

You still want the profit to equal PSl but after commission. Therfore, you need to make a little more profit so that after commission it is PSl again.

Therefore Profit = [P/(1-C)]Sl - essentially replace every P in the equations above with P/(1-C)

The above equations now become

-SlOl+Sl+SbOb-Sb = [P/(1-C)]Sl (Eq.1)
Sl-Sb = [P/(1-C)]Sl (Eq.2)
Sb = Sl(1-(P/(1-C))) (Eq.2a)
Ob = Ol/(1-(P/(1-C))) (Eq.3a)

Using your example you have Sl, Ol and P and you want to find Sb & Ob
Sl = £2
Ol = 3
P = 0.1 (10% of LAY stake)
and say C = 0.05 (5% commission)

Eq.2a Sb = 2*(1-(0.1/(1-0.05))) = £1.79
Eq.3a Ob = 3/(1-(0.1/(1-0.05))) = 3.35

[Bhut]

Top reply!

Will digest this later today!

Cheers

Ian