Greyhound Question

I'm trying to devise a mathematical strategy for back dutching on the greyhounds.  My query is, how accurate is the price for the favourite just before start with at least £7000 matched volume?   We all know the favourite price in horse races is a very accurate indication of the winning chance, but in greyhounds with the much lower volumes it could be quite inaccurate.  Does anyone have a handle on this, or do I need to crunch an enormous amount of betfair data?

hi
the betfair greyhound fav wins approx 29% with prices at 1 sec before the start time.
max losses in a row using all tracks is 25.
i had lots of stats but found that i could not get an edge using odds, so i deleted all my old stats.
it would be no good using betfair or other results because most bots place bets upto 1 sec before the start time, but after 1 sec before the startime the fav changes so many times, so you could have stats for the fav winning x% but that is not the fav at 1 sec to the start time.
this is why i bought a custom bot to record the fav poss and odds at exactly 1 sec before the start time, i still use every now and again.
i would use months of my stats to make a system, then test it and go live for it to wipe my bank out after a few weeks to a month.
i think that the greyhound handicapper changes the rules every month or so, this way nobody can find an edge using any favourite.
as for using odds as an edge, why do you think that betfair keeps altering the way it adjust prices etc ( updates ), so that we cannot find an edge using the odds.

mcbee

Thanks mcbee, a very interesting post.
Like you I have also run what I thought was a successful strategy, that profited for months in a row, before wiping out the bank in a few weeks; but all previous attempts have been based around laying ranks 1 or 2.   

At moment I am looking at back dutching the higher odds dogs, when the favourite is higher than a certain price and also waiting for races where there is at least one outsider above a certain price.  This gives a better return than just laying the favourite in the same race providing the outsider doesn't win.  I have carried out some analysis of the betfair data to see the win frequency of  odds of say 12 or more and this still gives a better edge on average, than laying the favourite.

hi
here is an old spreadsheet that downloads the days greyhound bags meetings.
it saves having to go through all the days cards.
use the sheet marked racecards.
it has the greyhound name,form,best speed and column h is the speed rank.
i have had some profit from dutching the ranks 1 to 3.


mcbee

Spreadsheet opened, but gave a run error at one point, however the racecards sheet seemed OK apart from the race times being out by about 10 min.

Thinking about it though, I once bought a system that came with some software that would scrape the racecards for this data and you could specify which speed ranks to include.  It would output a txt or csv file that you could import into your bot.  It would also filter dogs based on number of wins, seconds, thirds etc as the system was to LAY (yes lay) the fastest dog if it had won the last one or two races, on the premise that dogs don't often win twice or three times in a row.

I might have another look, now you've mentioned profit from dutching the fastest 3 dogs.

hi
the other way is to back them with level stakes, you get some nice priced winners.
the software that you used was mal's scraper with mal's greyhound system.
i did a test on it and his staking plan but it failed short term due to the set % been to high to cover the losses in a row.
apart from that it was a good system.

mcbee

Thanks for contributing to this thread mcbee, its given me a few new ideas.  At the moment my back dutch ranks 2 - 5 based on certain prices is doing well.  I think of it as laying the favourite but with an improved edge as the lay prices are usually too high.

hi
at the moment i have been lay betting the fav in place markets, you would be surprised at how many do not get in the first 2 and the lay odds are a lot less.
i have checked a few of the old results for mals system and there are lot again that did not finnish in the first 2 in place markets, again the odds are a lot less.
you have got me working on mals system again, but in place markets, less odds better recovery.

mcbee

hi
at the end of the day or when you have finnished or any time before the next day.
with the spreadsheet, if you press ALT+F8
then select Geteverything.
select RUN
it will get the results for all the races upto the time.

mcbee

why do you think that betfair keeps altering the way it adjust prices etc ( updates ), so that we cannot find an edge using the odds.

Hi MCBEE

As ever a very insightful and interesting thread from you and Rubold. I could not help being fascinated by the above quote.

Recently an approach with "non hcap" horse races by laying certain selections at certain prices relative to the relationship with the Betfair forecast and the Racing post forecast has fallen off the edge of a cliff!

For 18 months it worked well profiting nicely every month. Now for three straight months we are flat to slightly down.  Could you clarify the above and possibly your thoughts in relation to how (if at all) it may be possible for this to effect my market?

The markets are forever evolving .. as more and more people come up with their own systems.

I had a system last year for races that was also making steady cash in-play, seems the markets have become more efficient and it has fallen over.

to the greyhound subject .. I am always interested in them sue to the sheer volume of races and am yet to come up with something concrete, though things are looking promising of late!

hi betfair winner
that is interesting, because earlier this year i did a test with betdaq using greyhound place markets, now i know this has nothing to go with what your quest is or maybe it has.
but earlier this year i showed a good profit with betdaq using the place markets, then i changed my system and used betfar.
yesterday i thought that i would check betdaq again to see how it has improved.
there are NO odds available in the greyhound place markets, nobody is even making offers.
and the horse place and win markets are just as bad.
horse racing , ripon 15:10
win market betdaq 3.855 matched
win market betfair 52.124 matched
place market betfair 10.431 matched
place market betdaq 33.00 matched
horse racing is no better

so you can see from betdaq point that punters have moved to betfair OR given up.
but this would effect all the markets prices.
the answer to your problem is within your results.
you will have to check back to see what the average odds were and what they are now.
a few years ago i ran a greyhound system that produce lots of profit, then all of a sudden it failed (after a betfair update).
when i looked back i found that the average price had moved up from (3.3 to 4.4) to (3.5 to 4.6) and this was enough to throw my system out of sync.
this happens every time they do an update.
it is the same as the lottery machine, they use a different one every time so that nobody can find an edge with one machine.
same with handicapping, if they did the same rules month in month out, we would find an edge, it would be to easy for us.

H'mmm
that's a lot of writing.
mcbee
 

Hi guys, may I throw in an idea?

I checked greyhound results from Nov 2011 till yesterday and grouped dogs by the trap number. And look what I've got:

The labels show average and maximum prices at the scheduled time.
Is it strange that 5th trap wins significantly less? Does anybody know why the 5th trap is so bad?

There is some trap bias that varies from track to track, but nothing that is easy to exploit.   I doubt you would see the same affect if you looked at other data series.

hi triggers.ru
where are the results from.
as all the results that i check year after year, is only a few percent difference between all traps at all tracks.


mcbee