Rugby Quarb System

[Wumpking]

Bulls bet not matched and now lapsed

£16.23 of Waratahs bet matched @ 1.43

Chiefs bet matched in full @ 1.20

[Wumpking]

Assessment of remainder of weekend's matches:

Match No.	Date	Tournament	Home Team	Best Odds	Av Odds	Av Odds +5%	Av Odds +7%	Selection
379	08/03/2008	Guinness Prem	Bath	1.28	1.19	1.25	1.27	Bath
380	08/03/2008	Guinness Prem	Gloucester	1.61	1.51	1.59	1.62	No Bet
381	08/03/2008	Guinness Prem	Worcester	2.62	2.51	2.64	2.69	No Bet
382	08/03/2008	Top 14	Bayonne	3.25	2.80	2.94	3.00	No Bet
383	08/03/2008	Top 14	Brive	1.61	1.54	1.61	1.64	No Bet
384	08/03/2008	Top 14	Albi	1.61	1.52	1.60	1.63	No Bet
385	08/03/2008	Top 14	Dax	2.75	2.55	2.68	2.73	No Bet
386	08/03/2008	Top 14	Stade Francais	1.14	1.10	1.16	1.18	Possible via Betfair
387	08/03/2008	Top 14	Montpellier	1.20	1.17	1.23	1.25	Possible via Betfair
390	09/03/2008	Guinness Prem	Leeds	2.87	2.51	2.64	2.69	No Bet
391	09/03/2008	Guinness Prem	Saracens	1.66	1.60	1.68	1.71	No Bet
392	09/03/2008	Guinness Prem	Wasps	1.49	1.40	1.47	1.50	Wasps

2 selections via the bookies:

Bath - £87.00 @ 1.28 with Victor Chandler -
Wasps - £65.00 @ 1.49 with BetChronicle -

2 potential selections via Betfair. As such, I've requested the following amounts/prices:

Stade Francias - £62.00 @ 1.18
Montpellier - £59.00 @ 1.25

[Wumpking]

Thanks for the response. I'm always a bit reluctant to post as it seems easy to cause offence to some people but you seem thick skinned!!!

I've found that a lot of forumites on this site will respond to constructive input. Don't be reluctant to contribute as you obviously know your onions, so to speak.

there is evidence from Paton and Williams et al that the longshot bias is less prevelant when using the exchanges and, in some instances, there may actually be a negative bias rather than a positive one in some markets, particularly those which attract more serious investors than the casual punter

I certainly agree with you here. I calculate the mean odds from bookies odds only. This hopefully avoids any potential negative bias from using exchange derived odds.

Regarding the overround, I wasn't aware it was this low (is this the Betfair overround or the fixed odds overround because I can't recall Laddies and others ever being so generous?) so again, your research is clearly better than mine.

This is a fixed odds overround. You are right however, that no one bookie is likely to be so generous as to offer this sought of margin. The reason it can be so low is because the overround is based on the best odds for the home, away and draw offered by any bookie for the event. I record these odds on the spreadsheet I use to analyse the data.

Having said that, a 103-4-5% overround will surely effect your figures and would need to be factored in

I hope I do this. Firstly, by calculating the mean odds from at least 8 or so bookies prices (all of which would have the overround incorporated into them) and then by not betting unless the best price is 5% above the mean (which also would have the overround incorporated into it).

Going back to the longshot bias, I still think this needs to be factored in because the point with the quarb is that you're attempting to discover the true price of an event occurring and then bet accordingly if the price is outside the true range. You can't discover the true price if you don't factor in all the variables. Just my opinion of course, like I said the fact you're well into profit lends weight to whatever argument you care to make

It is extremely difficult to determine the true price prior to an event occuring. Many systems, for example, use very complex methodology in an attempt to determine this. I do use different approaches in an effort to do this in other areas of my betting. However, for this system I use the consensus market price as a good indicator of ‘true’ probability. This at least draws upon the expertise of a number of specialist rugby odds compilers.

2.1% in my view is a significant enough % for me to want to take account of it, particularly when I'm working to a 5% difference and am failing to account for the overround and longshot bias

Yes the draw can have an impact, however, I still feel this is limited in Rugby and therefore, in this system. As discussed, I do not think I fail to take into account for the overround or the longshot bias.

Again, I repeat, I'm impressed with your profit and like your thinking - just trying to stimulate a bit of debate as this is an area I've given close attention to. In fact, I know a city trader who adopts a quarb based strategy for the markets, with success I might add

I certainly do welcome the debate. I want to review the system at the end of the season with the ambition of improving upon it for next year. That is of course if it continues to be profitable!! Glad to hear others are using quarb approaches with success in other fields. I've wondered whether the approach would work in sports such as tennis? The other area that I think lends success to my approach is the staking plan I use. This limits risk as well as allows for good growth potential.

I hope your selections come in for you this weekend

Me too!!!!

Thanks again for the input. I hope the reply is useful.

[aliasme]

Hello again!

Fair points, well made.

I think we may have to agree to disagree about the overround. Whilst I take your points on board, I do think that if you're looking to bet 5% above the mean and the overround is 105% then for me this impacts a little too much into the figures for it to be in quarb territory. Especially, as you're not allowing for the draw. On this basis I would be inclined to adjust the 5% minimum up a tick ot two?

As for the longshot bias - I was curious as to how prevelant this really was in the sphere of rugby and wondered what your profits would have looked like had you adopted your quarb approach to all home teams irrespective of their price, might be worth paper trading this aspect of the system?

I've wondered whether the approach would work in sports such as tennis?

I believe a quarb based approach to betting is a sensible, mathematically sound approach and of course when used with the Kelly Criterion I fail to see any long term downside. I don't see why this approach couldn't be used in any form of sports or financial trading although I think the less the number of particpants/outcomes the easier the calculations become, tennis on this basis is probably a very sensible suggestion.

All the best.

[Wumpking]

France, Stade Francias and Montpellier bets were all unmatched (France and Montpellier both won, but Stade lost). Results update for weekend:


Reds lost against Stormers 16 - 34

Chiefs beat Cheetahs 22 - 20

Waratahs beat Brumbies 24 - 17

Bath beat Newcastle 22 - 11

Wasps beat Harlequins 29 - 25


Systems update:

Starting Bank	£1,000.00
Current Bank	£1,402.19
Total Staked	£5,733.95
Number of Bets	116
Winning Bets	92
Losing Bets	24
Strike Rate	79.3%
Yield	7.0%
Profit / Loss	£402.19

[Wumpking]

I think we may have to agree to disagree

Often the best way to end a debate

On this basis I would be inclined to adjust the 5% minimum up a tick ot two

You could be right. As previusly stated, at the end of the season I intend to review the system to try an improve it. One of the things I will assess will be the margin at which I feel a quarb occurs to see if profitability would be improved at say 6%, 7%, etc.

As for the longshot bias - I was curious as to how prevelant this really was in the sphere of rugby and wondered what your profits would have looked like had you adopted your quarb approach to all home teams irrespective of their price

Unfortunately, the favourite-longshot bias in theory only occurs in events where the favourite is heavily odds on. I use odds of 1.50 as my cut off but it could be argued that even this is too high and should be lower e.g. 1.40 or 1.30 (this is also something I intend to analyse at the end of the season). In this respect, it may not be possible to do what you suggest here. For example, in the Scotland v New Zealand game in RWC 2007, Scotland's mean odds were 43.80 whilst the best odds available were a staggering 53% higher at 66.00. They went on to lose by 40 points. An extreme example, but one which highlights why this system is likely to only work when the home team is heavily odds on.

I don't see why this approach couldn't be used in any form of sports or financial trading although I think the less the number of particpants/outcomes the easier the calculations become, tennis on this basis is probably a very sensible suggestion

I agree with you here. I just wish I had more time to be able to undertake this research.

Thanks again for the input, best wishes.

[Wumpking]

Assessment of first batch of this weekend's Super 14 matches:

Match No.	Date	Tournament	Home Team	Best Odds	Av Odds	Av Odds +5%	Av Odds +7%	Selection
394	14/03/2008	Super 14	Brumbies	2.00	1.95	2.04	2.08	No Bet
395	14/03/2008	Super 14	Chiefs	1.48	1.44	1.51	1.54	Possible via Betfair
396	15/03/2008	Super 14	Blues	1.22	1.19	1.24	1.27	Possible via Betfair
397	15/03/2008	Super 14	Crusaders	1.08	1.05	1.10	1.12	Possible via Betfair

3 potential selections via Betfair. As such, I've requested the following amounts/prices:

Chiefs - £49.00 @ 1.54
Blues - £59.00 @ 1.27
Crusaders - £67.00 @1.12

[Wumpking]

Chiefs bet matched in full @ 1.56

[Wumpking]

Assessment of tomorrow's Guinness Premiership match:

Match No.	Date	Tournament	Home Team	Best Odds	Av Odds	Av Odds +5%	Av Odds +7%	Selection
393	14/03/2008	Guinness Prem	Sale	1.57	1.48	1.56	1.58	Sale

Selection is:

Sale - £57.00 @ 1.57 with Stan James -

[Wumpking]

Assessment of the weekend's Six Nations matches:

Match No.	Date	Tournament	Home Team	Best Odds	Av Odds	Av Odds +5%	Av Odds +7%	Selection
398	15/03/2008	Six Nations	Italy	1.90	1.81	1.90	1.94	No Bet
399	15/03/2008	Six Nations	England	1.55