I'm looking at the BSP (Betfair Starting Price) in the files listed on http://promo.betfair.com/betfairsp/prices - taking just one race example from 20th November (see file dwbfpricesukwin20112019.csv)
MENU_HINT: GB / Ling 19th Nov, EVENT_ID: 165269925, EVENT_NAME: 2m Hcap Hrd, EVENT_DT: 19/11/2019 13:00
To narrow it down a bit further - we can just look at 3 runners - Flaminger, Ruacana and The Game Is A Foot
Before the off I took a snapshot of the BSPs. I then looked at the BSPs on the quick results page and finally the ones listed in the file
Flaminger: Pre-Off = 7.00, Quick-Results = 7.5, File = 8.312466855
Ruacana: Pre-Off = 2.63, Quick-Results = 2.63.5, File = 2.773462798
The Game Is A Foot: Pre-Off = 23.00, Quick-Results = 17.00, File = 27.00
Does anyone know why the pre-off and results differ and how the BSP incuded in the file is calculated?
Thanks in advance
That is because the PRE-Off is an indication - and that is all that it is, an INDICATION - based on the Amounts of money to both Back and Lay CURRENTLY (PRE-Off) sitting in the Betfair SP Market ONLY.
However - AT the OFF - the Betfair SP is THEN reconciled/worked out/applied - and that reconciliation ALSO THEN contains some, or any, UNMATCHED money from the PRE-Off Market - as is REQUIRED to make up for SHORTFALLS in the BSP MARKET where Back bets outweigh Lay Offers available, or vice-versa.
Straightforward solution - straightforward reason for your disparity observation.
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As regards the difference between "Quick Results" and the "File" Returns - can you define further what, and where, you mean by - "the BSPs on the quick results page".
If you mean betfair Timeform Results - such as ...
https://www.timeform.com/horse-racing/result/fairyhouse/2019-11-19/1435/208/5
Well - I am not so sure that most other users would normally refer to those Results as, "quick."
Nov 20, 2019 -- 9:56AM, onlooker wrote:
Understandable that the PRE-Off 'price' can be - in fact, almost INVARIABLY IS, every horse, every race - different to the Betfair SP.That is because the PRE-Off is an indication - and that is all that it is, an INDICATION - based on the Amounts of money to both Back and Lay CURRENTLY (PRE-Off) sitting in the Betfair SP Market ONLY.However - AT the OFF - the Betfair SP is THEN reconciled/worked out/applied - and that reconciliation ALSO THEN contains some, or any, UNMATCHED money from the PRE-Off Market - as is REQUIRED to make up for SHORTFALLS in the BSP MARKET where Back bets outweigh Lay Offers available, or vice-versa. Straightforward solution - straightforward reason for your disparity observation. -----------As regards the difference between "Quick Results" and the "File" Returns - can you define further what, and where, you mean by - "the BSPs on the quick results page".If you mean betfair Timeform Results - such as ...https://www.timeform.com/horse-racing/result/fairyhouse/2019-11-19/1435/2... - I am not so sure that most other users would normally refer to those Results as, "quick."
Thanks for your reply. The "quick results" page I'm referring to is the page that is displayed on Betfair as soon as the race have completed.
onlooker has explained the pre-off issue.
The "17" you quote as "quick result" for The Game Is A Foot is the Industry SP - where on the Betfair site are you seeing this?
As for how "how the BSP incuded in the file is calculated" - this is the actual BSP, and the calculation is explained on the pages linked from here:
https://promo.betfair.com/betfairsp/index.html
where you will also find an explanation of how the "Near" and "Far" projections (your "pre-off") are calculated.
