Carry Forward -.50c

GWS vs Port Adelaide 2.10pm
Lay at $12.50 Back at $10.00
Lay at $1.08 Back at $1.11

Adelaide vs Melbourne 4.40pm
Lay at $1.10 Back at $1.09
Lay at $10.50 Back at $11.50

Brisbane vs Sydney 7.40pm
Lay at $4.50
Lay at $1.25

Essedon vs Bulldogs 7.40pm
Lay at $1.34
Lay at $3.75

CP,

Just an observation, but from my dart board random assessment of a few of these across multiple sports, it appears in 90% of cases the favourite firms (or stays the same) and the long shot drifts.

What is your feel for this ?

Carry Forward -.50c

GWS vs Port Adelaide 2.10pm
Lay at $12.50 Back at $10.00
Lay at $1.08 Back at $1.11 WON +.30c

Adelaide vs Melbourne 4.40pm
Lay at $1.10 Back at $1.09
Lay at $10.50 Back at $11.50 WON +$10 Get in!

Brisbane vs Sydney 7.40pm
Lay at $4.50
Lay at $1.25

Essedon vs Bulldogs 7.40pm
Lay at $1.34
Lay at $3.75

It's fairly even when you look at the amounts.
Often it will stay the same or firm a little, but when it drifts it compensates more.
So you end up a little better off laying first then backing.
But you are right by strike rate.

Carry Forward -0.50c

GWS vs Port Adelaide 2.10pm
Lay at $12.50 Back at $10.00
Lay at $1.08 Back at $1.11 WON +.30c

Adelaide vs Melbourne 4.40pm
Lay at $1.10 Back at $1.09
Lay at $10.50 Back at $11.50 WON +$10 Get in!

Brisbane vs Sydney 7.40pm
Brisbane Lay at $4.50 Back at $6.00
Sydney Lay at $1.25 Back at $1.19

Essendon vs Bulldogs 7.40pm
Essendon Lay at $1.34 Back at $1.32
Bulldogs Lay at $3.75 Back at $4.00

I'm trying to work out the profit on these. So this might help others understand it.

GWS vs Port Adelaide.
Lay at $12.50 Back at $10.00 = Back and Lay cancel each other out.
Lay at $1.08 Back at $1.11 WON +.30c = (10*(1.11-1.08)) = 0.30

Adelaide vs Melbourne 4.40pm
Lay at $1.10 Back at $1.09 = Back and Lay cancel each other out.
Lay at $10.50 Back at $11.50 WON +$10 = (10*(11.50-10.50)) = 10

Thanks for posting the prices.

Yep, thanks

Thanks to you two 'tag team champions'. Starting to get it now.

Yes, sorry I haven't given full calculations, I do this day in and day out so I forget that it does need a bit of explanation. Once you get the calculations, it just becomes automatic mental arithmetic.

Basically you don't need to work out any calculations for the losing side, only the winning side. It's just (back odds - lay odds) * stake (less commission)

For those who not use to betfair. The reason you don't have to worry about the losing side is because you layed it for $10. So you get back $10 because the team lost. You have also backed it for $10 to win so your winning on the $10 lay just pays back your losing of $10 on the back.

Its all simple when you understand it.