Change of display of unmatched bets on Betfair's website

[GaryRussell]

On 8th May 2009, Betfair made the following announcement. On certain markets you may notice a difference between the odds in Betting Assistant and the website. This is not a bug in Betting Assistant. The API is just returning the odds as it has always done.

As we promised last year, we’re planning to improve the way unmatched bets are displayed to website customers in many of our exchange markets, by reintroducing functionality the exchange had when Betfair first launched. Customers who’ve been with Betfair since the early years will recall that the website used to display unmatched bets in every way that they could be matched. What we mean by that is best illustrated by a simple example: an unmatched bet to back Andy Murray to win a tennis match at 2.0 would be shown in both ways that it could be matched – as an available lay of Murray at 2.0, but also his opponent as available to back at 2.0 too.

We expect to introduce this improvement on the morning of Tuesday 12th May. We will not be making changes to the way bets are matched. This change will mean that the display of available bets is consistent with the way bets are matched.

We’ve tried to answer some likely questions below:

Q: Why are you making this change? What is the benefit for customers?
A: If you put a bet up on the exchange we’ll now display that bet to other customers in every way that it can be matched, giving you a greater chance of getting matched. Customers coming to a market will see a greater range of available bets, and are more likely to find the bet they want at a price they’re willing to take.

Q: Which markets will be affected by this change?
A: We plan to roll this functionality out to all odds markets on the site, except those which can have non-runners (like Horse Racing win and place markets) and those where runners can be added (“Next Chelsea Manager” for example).

Q: Betfair used to have this functionality. Why was it switched off in 2002?
A: The calculation of which prices to display used to be done in our database, and we had to switch it off in 2002 because the site struggled to cope at very busy times. We’ve now found a way to calculate the prices to display that doesn’t involve our database, so we can reintroduce the functionality without affecting the performance of the site.

Q: Is there any downside for existing customers?
A: For the majority of customers, no. Customers who have automated strategies will find fewer riskless arbitrage opportunities, and customers whose strategies rely on offering prices less competitive than would be achieved by placing opposing bets on other selections will also find it harder to match other customers at poor prices.

Q: How will this change affect the performance and stability of the site?
A: We would expect performance and stability to improve. The functionality itself uses a part of Betfair’s system that has spare capacity and so there’ll be no negative impact. However we do have a number of customers who run automated programs on Betfair that continuously look for riskless arbitrage opportunities. Following this change there will be little incentive for customers to continue to develop such applications, so we would expect this to reduce load on the site over time.

Q: I access Betfair via the API. What changes will I need to make to my strategy?
A: You won’t have to make any changes. The available unmatched bets in each market will be represented via the API in exactly the same way they are now. We’re only changing the way bets are displayed on the Betfair website.


If you have any other questions please contact the helpdesk: bets@betfair.com

The Betfair Team

[GaryRussell]

In the latest Beta version (1.1.0.66g) we have used the cross matching formula supplied here http://bdp.betfair.com/index.php?option ... &Itemid=62 to display prices in line with the website.

It has only been applied to the following markets so far because there is no specific flag received from Betfair to indentify the markets where cross matching is applied. If you want it applied to a market type not in the list below then please let us know.

The calculation is turned off by default. It can be activated in general preferences.

Soccer
Match Odds
Over/Under 1.5/2.5 etc.
Bookings Match Bet
Bookings Odds
Clean Sheet?
To Score in Both Halves
Win Both Halves
Both Teams to Score?
Corners Match Bet
Corners Odds
Draw No Bet
First Corner
First Half Goals
Half With Most Goals
Hat-Trick Scored?
Next Goal
Penalty Taken?
Sending Off?
Substitutes Used
To Qualify
Total Goal Mins

Tennis
Match Odds

[greenfingers]

I'd suggest snooker frame odds and match odds, plus darts leg betting and match odds?

[GaryRussell]

I'd suggest snooker frame odds and match odds, plus darts leg betting and match odds?

I will include these markets in the next release.

[GaryRussell]

The following additional markets are now recognised in version 1.1.0.66h

Cricket
Match Odds
Tied Match

Snooker
Match Odds
Frame Betting

Darts
Match Odds
Leg Betting

[greenfingers]

Great, thanks Gary. I look forward to making use of that.

[GaryRussell]

New enhancement in version 1.1.0.66i

Added new option to grid preferences to highlight liquidity generated by cross matching. The odds and amounts generated are highlighted in pale yellow.

Also the following markets are now recognised for cross matching.
Boxing
Match Odds

Rowing
All Oxford v Cambridge boat race markets

Rugby League and Rugby Union
Match odds

[Bart]

Hey Gary finding this feature very useful any chance of including a couple more tennis markets namely Set Betting and Set 01/02 Winner. Thanks.

[GaryRussell]

I'm glad you are finding it useful. I will include the other markets in the next release which will be out in a day or two.

[GaryRussell]

Version 1.1.0.66m now includes the following markets.

Tennis
Set Betting
Set 01/02 Winner

[Bart]

Thanks Gary much appreciated

[NTG]

Hi, Thanks for this feature - is it possible that in a future version you could apply it to the rest of the tennis markets too (Total Games, Tie Break?, Number of Sets, 6-0 Set?, +x.5 Games) Thanks!

[GaryRussell]

Hi, Thanks for this feature - is it possible that in a future version you could apply it to the rest of the tennis markets too (Total Games, Tie Break?, Number of Sets, 6-0 Set?, +x.5 Games) Thanks!

Yes, I will try and include this in the next release.

[Bart]

Hope you don't mind a bump for these other tennis markets.

Also I have noticed that football correct score and half time correct score markets have cross matching applied on the website but are missing from BA. Thanks.

[GaryRussell]

Hope you don't mind a bump for these other tennis markets.

Also I have noticed that football correct score and half time correct score markets have cross matching applied on the website but are missing from BA. Thanks.

I'll release an update asap, hopefully tomorrow morning.