The rate of Horse Racing price change in-running

[firlandsfarm]

It's something I have never considered before but it's started to float around in my mind. Is there any research into how quickly prices fall (or drift) all other things being equal by which I mean ignoring the immediate changes when a horse falls or refuses.

I'm expecting it to be a bit like an upside-down exponential curve similar to the deterioration of the Draw in Soccer Mystic when no goal is scored. Does anyone know of any values/formulae/theories available. Yes, every race is different but so is every football match but that doesn't stop theories of how an average game might play out.

I'm looking at this because of the number of in-running bets not being matched so I'm thinking is there a way to estimate either a slightly earlier trigger to make sure your bet at the target price is matched or trigger as normal but set the target lower? Easy to do but am looking to judge what would be a workable margin between Trigger and Target.

[guy333]

I doubt whether comparing a football match and a horse race is very helpful. In a football match there are three outcomes win/draw/lose in a horse race there are two outcomes for the horse win/lose or numerous outcomes, if you look at the race as a whole and consider the other horses.

With the declining draw, the draw is in pole position and the chances of it happening obviously increase as the final whistle gets closer. With a horse race, being in pole position is not necessarily an advantage, as the front runner is often caught by other horses who have run more tactically. The odds are affected by how well the horse is running, so I can't see how any rigid formula could be applied.

[elofan0]

could depend on many factors sprints i assume would be fastest but i have seen a many prices just plunge on the flat

[JuiceyJones]

I saw a dashboard on Youtube last year.

It basically had recorded prices for all runners over 5 second intervals for all races over the last 15 years (i think). The dashboard would monitor all of the days races on betfair then at about 1-2 minutes before the off look through its database to find close matches to a race was about to start. Historical races that were close in price for each horse, trip, going, class etc. Then give average price moves from its historical data.

I have no idea if it worked or would work. Pretty sure you can do most of it in BA.

[ShaunWhite]

Is there any research into how quickly prices fall (or drift)

Rate of change and volume weighted momentum (where the rate of change has 'mass' , aka volume) are both valid signals to put in your algo. Usual problems choosing an appropriate time span for the delta though.

Aggressor imbalance is a good in-running indicator too, but I'm not sure if BA can identify tv changes per price, and then look back at whether that was a back or lay price at the time it changed.

[firlandsfarm]

Thanks for all your contributions guys ... I never thought it would be straightforward nor easy. As I said I'm looking for a way to try and improve bet matching in-running.

[elofan0]

surprising the drop soon as they go inplay for some example fav , here was 1 sec before 1 sec after In Play

[firlandsfarm]

surprising the drop soon as they go inplay for some example fav , here was 1 sec before 1 sec after In Play

I was aware of some price differences but never measured and never expected some of those margins ... are they posted back or lay odds or last traded price?

[elofan0]

Just best back Price, heres another race Australian, didnt monitor the Lay price

[jamesedwards]

Just best back Price, heres another race Australian, didnt monitor the Lay price

A few thoughts on what might cause this:
> The market is still reforming following in-play so could just be a large spread.
> A late withdrawal not yet removed from market (a future reduction factor would apply to bets matched before the off, but not after).
> Fast pics or trackside players backing a speedy starter out of the gates.

[ShaunWhite]

A few thoughts on what might cause this:
> The market is still reforming.

That's my take on it, the lay prices on offer are similarly poor and the spread closes quickly. And it's nearly all runners.

Might be a bit more competitive when the passive bet delay change comes in, gonna be a lot more interest in offering if there's less chance your offer will be stale by the time it's visible.

[elofan0]

either way it could possibly occur every race and possibly can even be seen on the graphs

[jamesedwards]

either way it could possibly occur every race and possibly can even be seen on the graphs

Only of interest if the just-off lay price or last traded price is consistently lower than the pre-off back price though?

[jamesedwards]

Just best back Price, heres another race Australian, didnt monitor the Lay price

A few thoughts on what might cause this:
> The market is still reforming following in-play so could just be a large spread.
> A late withdrawal not yet removed from market (a future reduction factor would apply to bets matched before the off, but not after).
> Fast pics or trackside players backing a speedy starter out of the gates.

Another one (rare) that I used to see occasionally in low-liquidity US races, and presumably still occurs:
> Someone goes to take a largish-volume chunk with an extreme override just as the race happens to go in-play. All the liquidity vanishes on in-play leaving them taking the market down to much lower than they anticipated. I've even seen this accidently sweep the entire book down to 1.01 before.

[elofan0]

Great observation James