Retrospective - API Release To Prevent Minimum Bet Abuse - 19th June

[LiamP]

We made an emergency release earlier today to prevent consistent attempts to take advantage of bet rounding.

Any bets that are placed to benefit from rounding will now be rejected with the error INVALID_PROFIT_RATIO

Apologies for the lack of notice regarding this urgent release.

Betfair Developer Program

This is unbelievable.

Surely you did a quick MI on the impact this would have before releasing to production without warning users, I can't honestly believe it.

You have allowed this for 20 odd years, I am sure it could wait 1 more week.

[geoffw123]

This is unbelievable.,

Agreed, they also compounded the problem by not explaining in detail what the change was, they left us to try and figure it out. In addition they dont seem to have have made a 2nd statement on the issue, despite all the App. forums blowing up with complaints yesterday from Developers and users alike.

I would phrase it a little differently than when you said "You have allowed this for 20 odd years,", as I would say, being able to green up with sub 2 pounds is a vital and important feature all Apps need to be able to do.

It does make you wonder why BF just didnt simply suspend the account of the abuser, rather than cause chaos with a rushed ill thought out modification ?

[WTPooh]

You can use different odds for different sizes. Here is my results for different sizes:

size price
0.01 1.8
0.02 1.4
0.03 1.27
0.04 1.2
0.05 1.16
0.06 1.14
0.07 1.12
0.08 1.1
0.09 1.09
0.1 1.08
0.11 1.08
0.12 1.07
0.13 1.07
0.14 1.06
0.15 1.06
0.16 to 0.19 1.05
0.2 to 0.26 1.04
0.27 to 0.39 1.03
0.4 to 0.62 1.02
0.63 to 0.79 1.03
0.8 to 1.24 1.01
1.25 to 1.59 1.02
1.6 to 1.99 1.01

But there are some other problems. For example you can't have a lay bet 1.49@1.01.

[bfexplorer]

URGENT

I understand that there must be an urgent need for the change, but this was unplanned and is causing havoc for API software users.

So I must ask you to consider reversing this change immediately and instead just block the accounts of anyone found to be abusing bet rounding. That would at least give us the chance to work together to come up with something in an orderly manner that doesn't cause havoc for innocent software users and software suppliers!

Thank you.

Cymatic, I agree with you only with one point, there is no documentation for this error message and basically betfair documentation is big mess, a lot of changes are not documented. Missing enum entries and so on..

On the other hand, it is betfair T&C and they can do whatever is better for betfair business model.

I hope you will not start quarrel like geoffw123 started on another thread when I stated my opinion.

Yes, betfair tolerated placing bet under minimal bet size and we all betfair software vendors implemented that algorithm, but it seems not all vendors do what they are doing right?

Because when during this "small bet placement" operation if anything goes wrong you need to cancel original minimal + small bet stake, and not leaving it on market as your software and bet angel does. Because then of course user could take actually bigger loss than with it original bet opening trading session.

Watch my video, showing my app:

https://youtu.be/Xf5ysUiBzPU

When bet placement failed original bet was cancelled.

My app offers more automation than your one, and when user places bets manually then he/she notice error messages when placing small bets, so it is his responsibility to act correctly.

When small bets are placed in automation, I have got a lot of such bots called Close Bet Position, then even such bots when places small bet detects error and stops its activity.

Well basically users place bigger bets when trading either manually or fully automatically, so problems could occur only when my closing bots try to level profit loss evenly to all selections, so small bets are being placed, and in my video you can see that betfair still accepts small bets, well you mentioned that as well, 0.8 stake amount, but on my video you can see that on back side I was able to place even 0.5 Eur stake.

I set limits to my bots to 0.4 * MinimumBetSize defined by betfair per different currencies.

[WellDoneSoft]

Hello!

I have repeatedly attempted to lay 0.2 at prices up to 100.0, and failed.

So this:

size price
0.01 1.8
0.02 1.4
0.03 1.27
0.04 1.2
0.05 1.16
0.06 1.14
0.07 1.12
0.08 1.1
0.09 1.09
0.1 1.08

does not appear to be valid at the moment: it could have been so yesterday.

I initially thought the new change meant to prevent users laying to liabilities less than 0.01, but the above does not tally with this assumption, as the liability of £0.1 @ 100 is £9.9 and yet no bet is placed.

[WTPooh]

To lay 0.2@2:
1. Lay 2@1.04
2. Cancel 1.80
3. Replace price with 2

For me everithing works fine.

[WellDoneSoft]

For me everithing works fine.

Except when you need to lay at 1.03 or less than £0.2, then it becomes tricky, doesn't it.

[WTPooh]

You can lay any size from 0.01 to 1.99. Just use a price from my first post.
But there are several limitations for resulting price: 1. Liability must be >= 0.008 (you can't lay 0.2@1.03) 2. Some sizes will not be acceepted (like 1.49@1.01).

[LayItYouMug]

(0.008D / stake) + 1 gives you the odds for your initial lay bet. Just round it up to nearest odds.

[WTPooh]

(0.008D / stake) + 1 gives you the odds for your initial lay bet. Just round it up to nearest odds.

Not exactly. There are some exceptions. Try for stakes 0.63 to 0.79 and 1.25 to 1.59.

[LayItYouMug]

Not exactly. There are some exceptions. Try for stakes 0.63 to 0.79 and 1.25 to 1.59.

You are right. Hmmm

[Sansa]

The first post on this thread has been updated at 9:40am today. Yet until I posted this it looked like nothing been said on this topic since 3:13pm yesterday.

[BOTTYBO]

You can use different odds for different sizes. Here is my results for different sizes:

size price
0.01 1.8
0.02 1.4
0.03 1.27
0.04 1.2
0.05 1.16
0.06 1.14
0.07 1.12
0.08 1.1
0.09 1.09
0.1 1.08
0.11 1.08
0.12 1.07
0.13 1.07
0.14 1.06
0.15 1.06
0.16 to 0.19 1.05
0.2 to 0.26 1.04
0.27 to 0.39 1.03
0.4 to 0.62 1.02
0.63 to 0.79 1.03
0.8 to 1.24 1.01
1.25 to 1.59 1.02
1.6 to 1.99 1.01

But there are some other problems. For example you can't have a lay bet 1.49@1.01.

Yep this is the answer. And original post updated and makes sense now.

[oldBloke]

not sure if the above listed odds are correct.

Want a 0.07 lay bet @ 1.18.

This CAN be placed at 1.12

But cannot be moved to 1.18

[bfexplorer]

You can place 0.8 stake amount at 1.01, watch my video:

https://www.youtube.com/watch?v=Xf5ysUiBzPU