Rugby Quarb System

[Wumpking]

This system will focus on identifying 'Quasi-arbitrages' or 'Quarbs' in fixed odds rugby union matches and exploiting these as hopefully profitable betting opportunities.

In essence, a Quarb occurs where one bookmaker is offering prices out of line with their competitors but not so far apart from the others as too cause an arbitrage. The theory of Quarbs was first outlined in the work of Paton and Vaughan Williams (2002) in 'Quarbs' and Efficiency in Spread Betting: can you beat the book? This theory was further developed and applied to fixed odds betting by Smith, Paton and Vaughan Williams (2005) in Information Efficiency in Financial and Betting Markets. The system also draws upon other weak form information inefficiency theories, particularly the ‘favourite-longshot bias’, whereby low probability outcomes are overvalued and high probability outcomes are undervalued. Other forumites, particularly mcgin, have analysed the ‘favourite-longshot bias’ in rugby - see for example http://www.punterslounge.com/forum/showthread.php?t=38441 Indeed, this system owes much to mcgin’s work outlined in this thread and is based on his original paper/real life trial so many thanks mcgin - :notworthy The rules of the Rugby Quarb System are as follows:

• Only home sides in rugby union matches, both domestic and international, will be considered for betting purposes. This is because there is a strong home bias in rugby (e.g. 68.5% of games played over the last 3 seasons in the Magners League were won by the home side). Furthermore, the draw outcome has limited impact (e.g. only 2.1% of games played again in the Magners League over the same period were drawn).
• Only mean odds of 1.50 or less will be considered from an analysis of at least 8-10 bookmakers’ prices (normally using the Odds Comparison website). The underlying assumption of the system is that the consensus market price is a good indicator of ‘true’ probability. In this respect, the subjective probability of the home side winning a match will be at least 66.7%.
• Where a bookmaker’s price is out of line with the mean by at least 5% or more (or 7% for Betfair to take into account commission), a Quarb or betting opportunity is considered to occur.
• Stakes are based on the Kelly criteria with an added modification to limit risk and are calculated by the following formulae: Current Total Bank x % Difference between Mean Odds and Best Odds x Subjective Probability of Winning (as derived from the mean odds).

I tested this system on all Rugby Union games during Feb – May 2007 and had a strike rate of 85.4% and yield of 16.9%, hence this will be a real life system and will start with a bank of £1,000.

Would appreciate any input / suggestions for improvement from other forumites.

[Wumpking]

Re: Rugby Quarb System

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
1	31/08/2007	Magners League	Cardiff Blues	1.61	1.50	1.55	1.63	No Bet

[mcgin]

Re: Rugby Quarb System

The system also draws upon other weak form information inefficiency theories, particularly the ‘favourite-longshot bias’, whereby low probability outcomes are overvalued and high probability outcomes are undervalued. Other forumites, particularly mcgin, have analysed the ‘favourite-longshot bias’ in rugby - see for example http://www.punterslounge.com/forum/showthread.php?t=38441 Indeed, this system owes much to mcgin’s work outlined in this thread and is based on his original paper/real life trial so many thanks mcgin - :notworthy

Cheers for the acknowledgment, although the original idea stemmed from from work done by Datapunter & the guy that runs football-data.co.uk :) Good luck anyway, I'm sure you will be successful as I saw every reason there were huge inefficiencies with some of the books out there (keep an eye on Stan James he was always providing some far out odds) A word of warning, you might want to be wary of anything > 1.30. I found those to be a bit dodgy when I was running this. Although that was more of a subjective thing rather then me tracking it and seeing the results. Am looking forward to the WC myself. I believe there will be plenty of short favs that will fall into the system and was actually thinking of resurrecting my old thread for it. Mightn't have to now :) Here's hoping you can beat my 33 in a row :dude

[trollerboy]

Re: Rugby Quarb System can you tell where to get infos about this for soccer?

[Wumpking]

Re: Rugby Quarb System Thanks mcgin for the input and good wishes. Funny you should mention Stan James. I certainly agree that they tend to offer good odds in terms of rugby prices. I'm also currently 11 from 11 with them for rugby bets so enjoy betting with them! Whilst I appreciate the warning in betting at odds > 1.30, I've found the system works well up to 1.50. I feel the risks are manageable, particularly as the staking plan is also linked to the mean odds. Your run of 33 in a row was fantastic and sets the milestone - :notworthy. I was sorry to see your thread end at this point. I'm not confident this system will match that type of run as I expect it to lose around 10-15% of the time. I just hope it starts well :hope.

[Wumpking]

Re: Rugby Quarb System

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
2	01/09/2007	Magners League	Scarlets	1.37	1.33	1.35	1.42	No Bet

Whilst Scarlets potentially qualify as price

[Matthew]

Re: Rugby Quarb System Good luck with this Wumpking. Looks very interesting.

[Wumpking]

Re: Rugby Quarb System

Good luck with this Wumpking

Thanks Matthew for the good wishes. Fortunately for the system, Scarlets price on Betfair never reached 1.44 as would have been a losing bet! :$

[Wumpking]

Re: Rugby Quarb System Enough bookmakers have priced up Friday's opening match of the RWC to assess. France potentially qualify but are currently no value. Will monitor during week just in case any additional bookmaker’s prices are set out of line with the mean odds.

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
3	07/09/2007	RWC 2007	France	1.20	1.12	1.18	1.24	No Bet

[Wumpking]

[Wumpking]

Re: Rugby Quarb System

Unlikely that France's price will meet the system requirements for a bet

Thankfully it didn't as again would have been a losing bet!

[Wumpking]

Re: Rugby Quarb System Have now assessed the matches for the 12th Sept as enough prices available:

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
12	11/09/2007	RWC 2007	Argentina	1.00	1.00	1.00	1.05	No Bet
13	11/09/2007	Magners League	Ospreys	1.40	1.28	1.34	1.40	Ospreys

Argentina game is a no bet as no value can be obtained. However, the Ospreys qualify for what is the first bet of the system. Selection is Ospreys - £35.00 win @ 1.40 with Blue Square - :hope.

[Wumpking]

Re: Rugby Quarb System Enough prices available to assess the Tonga v USA match on the 13th Sept:

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
14	12/09/2007	RWC 2007	Tonga	1.40	1.22	1.29	1.36	Tonga

Selection is Tonga - £63.00 win @ 1.40 with Blue Square - :hope.

[F.]

Re: Rugby Quarb System Hello, First of all, rugby is not my sport... I barely know the rules :$ but I regard it as one of the best sports to watch once you get the hang of it... Anyway, I got interested in your system because you are basing it in sound mathematical theories:

The theory of Quarbs was first outlined in the work of Paton and Vaughan Williams (2002) in 'Quarbs' and Efficiency in Spread Betting: can you beat the book? This theory was further developed and applied to fixed odds betting by Smith' date= Paton and Vaughan Williams (2005) in Information Efficiency in Financial and Betting Markets. The system also draws upon other weak form information inefficiency theories, particularly the ‘favourite-longshot bias’, whereby low probability outcomes are overvalued and high probability outcomes are undervalued.

Not only your selection criteria seems solid, you are basing your staking plan in Kelly's criterion, also very solid (mathematically speaking)

• Stakes are based on the Kelly criteria with an added modification to limit risk and are calculated by the following formulae: Current Total Bank x % Difference between Mean Odds and Best Odds x Subjective Probability of Winning (as derived from the mean odds).

As I'm sure you already know the main downside to Kelly's staking plan is that your bank will be on a "rush mountain ride", but your risk limitation variant should smooth it out... I'll be following with interest. Best of lucks to you... :hope F.

[Wumpking]

Re: Rugby Quarb System

I'll be following with interest. Best of lucks to you... :hopeF.

Thanks F. for the interest and good wishes, it is much appreciated. Sadly the system has got off to the worse possible start with the Ospreys losing at home to the Scarlets :@ :wall :@. As such, the current status is:

Starting Bank	£1,000.00
Current Bank	£965.00
Total Staked	£35.00
Number of Bets	1
Winning Bets	0
Losing Bets	1
Strike Rate	0.0%
Yield	-100%
Profit / Loss	-£35.00

[F.]

Re: Rugby Quarb System It is still too early to tell. Don't despair !! F.

[Wumpking]

Re: Rugby Quarb System Early days indeed F. It is Sod's Law however, that the first bet of the new rugby season would lose. Also particularly galling as the Ospreys haven't lost at home in the Magner's League since May 2006! As you state, Patience is the key, Discipline is the way...

[Wumpking]

Re: Rugby Quarb System Assessment of matches later today are as follows:

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
15	12/09/2007	RWC 2007	Fiji	1.10	1.02	1.05	1.10	Fiji
16	12/09/2007	RWC 2007	Italy	1.03	1.00	1.01	1.06	No Bet

No value can be obtained on Italy. Fiji just about qualify. Selection is Fiji - £49.00 win @ 1.10 with Betandgame - :hope.

[Wumpking]

Re: Rugby Quarb System

Tonga - £63.00 win @ 1.40 with Blue Square

Thankfully, Tonga beat the USA 25 -15 to give the system its first win :cow

Starting Bank	£1,000.00
Current Bank	£990.20
Total Staked	£98.00
Number of Bets	2
Winning Bets	1
Losing Bets	1
Strike Rate	50.0%
Yield	-10.0%
Profit / Loss	-£9.80

[2hcb]

Re: Rugby Quarb System bet you were getting nervous during the Fijian game wumpking!!

[Wumpking]

Re: Rugby Quarb System Fiji just about hang on to beat Japan 35 - 31 :cow

bet you were getting nervous during the Fijian game wumpking!!

Wasn't able to watch the game and didn't know the result until having only just watched the highlights. Phew! I hope in future there aren't that many 1.10 shots that end up being that close. System update:

Starting Bank	£1,000.00
Current Bank	£995.10
Total Staked	£147.00
Number of Bets	3
Winning Bets	2
Losing Bets	1
Strike Rate	66.7%
Yield	-3.3%
Profit / Loss	-£4.90

Despite a losing start the system is nearly back in the black.

[Wumpking]

Re: Rugby Quarb System Assessment of the South Africa v England game as follows:

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
17	14/09/2007	RWC 2007	South Africa	1.15	1.08	1.11	1.17	No Bet

Whilst South Africa potentially qualify as price

[Wumpking]

Re: Rugby Quarb System South Africa bet was matched in full! Bet therefore is South Africa - £45.00 win @ 1.19 with Betfair - :hope.

[Wumpking]

Re: Rugby Quarb System South Africa beat England 36 - 0 :cow System back in the black and showing a small profit!

Starting Bank	£1,000.00
Current Bank	£1,003.22
Total Staked	£192.00
Number of Bets	4
Winning Bets	3
Losing Bets	1
Strike Rate	75.0%
Yield	1.7%
Profit / Loss	£3.22

[Wumpking]

Re: Rugby Quarb System Assessment of the matches on the 15th Sept:

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
18	15/09/2007	RWC 2007	New Zealand	1.00	1.00	1.00	1.05	No Bet
19	15/09/2007	RWC 2007	Wales	5.50	3.50	3.96	4.16	No Bet
20	15/09/2007	RWC 2007	Ireland	1.01	1.00	1.00	1.05	No Bet
21	15/09/2007	Guinness Prem	Bath	1.69	1.53	1.61	1.69	No Bet
22	15/09/2007	Guinness Prem	Harlequins	2.25	2.10	2.18	2.28	No Bet
23	15/09/2007	Guinness Prem	Wasps	2.25	2.00	2.12	2.23	No Bet

No bets on any games as no qualifiers.

[F.]

Re: Rugby Quarb System

South Africa beat England 36 - 0 :cow

Just be careful on the celebration, remember this forum is full of English guys !! :lol

System back in the black and showing a small profit!

The way it should be !! :ok F.

[Wumpking]

Re: Rugby Quarb System Cheers F. :ok Two matches for tomorrow assessed (will do rest later although none likely to qualify):

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
24	16/09/2007	RWC 2007	Samoa	1.11	1.04	1.07	1.13	No Bet
25	16/09/2007	Guinness Prem	Newcastle	1.53	1.33	1.46	1.53	Newcastle

Current price on Betfair for Samoa is 1.15 which is the minimum price required (taking into account commission). Therefore, bet is Samoa - £47.00 @ 1.15 with Betfair - :hope. Other selection is Newcastle - £33.00 @ 1.53 with SkyBet - :hope.

[Wumpking]

Re: Rugby Quarb System Remaining matches for tomorrow assessed:

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
26	16/09/2007	RWC 2007	Fiji	2.05	1.67	1.91	2.01	No Bet
27	16/09/2007	RWC 2007	France	1.01	1.00	1.00	1.05	No Bet
28	16/09/2007	Guinness Prem	Bristol	2.10	1.72	1.88	1.97	No Bet
29	16/09/2007	Guinness Prem	Leeds	6.00	4.00	4.74	4.98	No Bet

No bets on any games as no qualifiers.

[Wumpking]

Re: Rugby Quarb System Samoa lose to Tonga :@ :wall :@ Again very galling as Samoa have won the last 9 matches between the two and have not lost to Tonga since June 2000. Newcastle beat Sale by 33 - 12 :cow System once again back in the red:

Starting Bank	£1,000.00
Current Bank	£973.71
Total Staked	£272.00
Number of Bets	6
Winning Bets	4
Losing Bets	2
Strike Rate	66.7%
Yield	-9.7%
Profit / Loss	-£26.29

[Wumpking]

Re: Rugby Quarb System Assessment of tomorrow's match:

Match No.	Date	Tournament	Home Team	Best Odds	Worst Odds	Av Odds	Av Odds +5%	Selection
30	18/09/2007	RWC 2007	Scotland	1.03	1.01	1.02	1.07	No Bet

No bet as no value.