Queue Jumping at Betfair ?

[mrprobit]

is this going on ?

earlier after getting into war with someone elses bot, where I went in front them and they then went in front of me. they eventually gave up and pulled their money up beside me.

which I thought was sensible as there stakes were much larger than mine, however Ive been puzzled that money is still being traded on the market without anything being matched against me, despite the fact I am the front on the queue for almost every selection in the market.

so I've started recorded the amount matched and seeing when it changes to find out which was the last selection traded on. sure enough selections that I am top priced on and in front of the queue are being traded without anything being matched against me.

[2020vision]

Hi mrprobit,

Is this possibly because there are bets in front of you that are below the
minimum stake so you can not actually see them - but will show up as matched?

Just an idea - Michael

P.S. This kind of thing is prolific with the greyhounds btw. Happens to me an
awful lot - I think my bet should be matched but somehow someone is in front?
Or the money I wanted matching disappears? This then leaves me vulnerable!

P.P.S. The bots often wind me up because sometimes they never seem to
know when to stop - thereby making any profit for anyone minimal.

[mrprobit]

Hi mrprobit,

Is this possibly because there are bets in front of you that are below the
minimum stake so you can not actually see them - but will show up as matched?

Just an idea - Michael

P.S. This kind of thing is prolific with the greyhounds btw. Happens to me an
awful lot - I think my bet should be matched but somehow someone is in front?
Or the money I wanted matching disappears? This then leaves me vulnerable!

nope, I had £5 at the front of the queue on a selection, about £500 behind. been about £50 traded on this selection in various chunks and it's all coming off the £500.

[2020vision]

Then what you say makes me suspect Betfair are at it themselves?

[mrprobit]

I'm going to check 2moro more rigoursly,shouldn't be to hard to prove if it's going on.

[2020vision]

I'm going to check 2moro more rigoursly,shouldn't be to hard to prove if it's going on.

That will be interesting? My opinion is that even if you do "prove" it Betfair
will not be in the slightest bit bothered - my experience is that they are a law
unto themselves and will do exactly as they please with their service and customers.

Good luck - Michael

[mrprobit]

They are, I know that the market in question has one of betfairs "preferred" liquidity suppliers operating in it and think that is who I was up against.

However the signature of their money was quite easy to read, so if it is happening I'll have to rewrite my bot to keep pushing my prices out when they draw up level.

hopefully we will reach a nash equilbrium state where they realise that queue jumping my £10 bet with a £500 bet is costing them more than they gain by queue jumping.

overall last night I had laid approx 320 selections, of which i was at the front of the queue for about 260-280 of them.

of the the £4k that was traded I got approx £40

something I should point out is that this market was in-running, but is of sufficiently low liquidity that it's possible to monitor individual bets being matched on the market.

[negapo]

Are there "preferred" liquidity suppliers?
Is this on the T&C?

[mrprobit]

Are there "preferred" liquidity suppliers?
Is this on the T&C?

I know that the people who I'm up against in this market get 500 accesses a sec through their API without incurring any data charges.

[Drunkenight]

Have you thought about using a screen recorder to record the market. Then you can play the video back at your leisure to see exactly what is happening on the market, when better offers are made, exactly which bets are matched, who was at the front of the queue when the matched volume on that selection increased etc.

[negapo]

mrprobit

Is that really true? Do they make requests from different users and then consolidate the data?

Are you sure that some bets aren't entering the market and being matched in a time frame inferior to your refresh rate? Or do you see that the second best price volume gets reduced in the same amount that was matched?

[Medwin2]

Hi, Would not surprise me if it's true. But I think Last price and Total amount matched after lagging a bit. So if you play when there is much movement, they will be misleading.

[Spamfree]

Betfair's cross matching bot?

[mrprobit]

Thought I would update this, played the same market again fri night and came up against the same bot again but it's behaviour had changed.

After going to "war" to see who could front the queue, this time instead of pulling it's money level against me it just pulled it all together. so on fri night my trades ended up constituting the vast majority of the money traded. so i didnt see the queue jumping again.

regarding my bet placement method, it simple, I calc the max i want to offer and offer the current bf price+1. if a price then moves in front I then offer that price+1. so I should always be at the front of the queue on those selections where the bf price is less than my max odds.

In my excel sheet I have a marker next to all the selections which tells me on which selections I am at the front of the queue.

on another sheet I am calling in the total amount matched, when this values changes it looks for the selection which has had the amount matched changed on and flags this up in my sheet aswell so I know which is the last selection to be traded.

[mrprobit]

Ive started to see this happen again, but think ive have discovered the source of the problem.

What's happening is that someone is putting up sub £2 lays in front of my prices. when bets are getting matched his sub £2 is getting laid first.

I didnt realise on the market I'm working on how many £2 bets are being placed, admitly I wasnt looking at how much the amount matched has changed last week, just the fact it has changed.

Any Ideas of how to defeat this parasite ?