Sunday 30 July 2017

National Steamers Away

A comment (above) via Twitter on my Black Cats and T-Bones post certainly hits the nail on the head.

Also via Twitter, and Statistical Trading ( @Statsbet ) has been keeping me busy validating various possible weaknesses in football markets. I became a little concerned when he asked me to take a look at Aways in League Two  - has he not been paying attention and reading this blog?

Shame! Back in February I wrote:
League Two is again where the Aways are leading the way, and for the sixth straight season, it looks like they will end above the 30% level.

Using Pinnacle's Closing prices, this continues to be a money-spinner, but don't tell everybody
Apparently this joke was taken literally, and no one told old Statty.

In May I published the final numbers in his post, although cautioning that "past performance is no guarantee of future success of course, especially in a division that churns 25% of its members each season, but one to watch next season."
Also via Twitter, and Miguel referenced an old post of mine from almost 18 months ago, which highlighted the challenges of finding an edge in the top leagues where you are competing with the likes of Starlizard, although 10% of EPL matches will be off-limits to them this season as:
Starlizard don't place any bets on Brighton, given Bloom and other directors' roles at the club.
As a Crystal Palace fan, one can only hope they are off-limits in the EPL for just the one season, although the six guaranteed points will come in handy as we push for a top four finish. I'm kidding of course - not about the top four finish, but the desire to see Brighton struggle this season. Tony Bloom deserves a lot of credit for what Brighton have achieved and so long as they finish below Palace, which most teams will do this season, the M23 derby (currently locked at 37 wins each, with 24 draws), and arguably up there with El Superclásico and the plain old El Clásico, sees a welcome renewal this season. 

As it's the eve of a new season, and most readers will forget this as soon as they've read it, I thought I might share a thought I had regarding the lower leagues. Back in May I mentioned that:
If you go too far down the football pyramid, you run into problems not only of liquidity, but also the problem where the VORP (Value Over Replacement Player) of certain key players becomes critical.
Many of you will be familiar with Skeeve, who has been profitable in the National League since forever. How does he do it? By studying the teams in great detail. See this post for an example. Since there are so few people studying this league to the extent that Skeeve does, he gets himself an edge.

Most of us don't have the time for this level of research and analysis however. 

As with League Two, backing Aways blindly in the National League over the past three seasons has been profitable.
Not that many of us have the time to do this, but were you to wait until close to kick-off, and limit your bets to Away teams who have drifted slightly (up to 2.5%) or shortened by up to 10%, your return increases to 93.25 points from a more manageable total of 912 bets (ROI 10.22%). 

An easier way to increase your ROI is to simply use the Home price as a filter, and back the Away team when the Home team has an Implied Probability in the 0.25 to 0.649 range +125.65 points from 1369 bets. 

I'll take a look at League One next and see how high up the food chain the steamer / drifter effect is seen. I'd expect it to be highest in the lowest division and decrease but we'll see. 

Friday 28 July 2017

Black Cats and T-Bones

Model Trader had a comment on my Top Notch post, writing:

I'm interested that you warn against waiting for statistical proof before getting involved? I can see why you might not want to wait for the routinely accepted definition of 'proof', where for certain areas, the bar is very high, but surely calculating some statistics (what is the likelihood that the edge occurred by chance) can only help?
I imagine that many times it's common sense. If I flip a coin 100 times and get 90 heads, I'm confident the coin is biased. If I get 51 heads, I intuitively know that I probably don't have an edge. But what about 55, 60, 65? Where do I draw the line? And let's say that I believe the 65 out of 100 coin is biased with a 0.65 probability of heads. Once I've started betting there's a very good chance that even with that edge, I'll be down at some point, so how do I decide when to get out because the edge has gone, rather than because of random chance?  
Model Trader ask some good questions. My thoughts on this are that betting markets are not ideally suited to the traditional standards of proof, mainly because they are constantly evolving and adapting and if any edge is present, it should soon be discovered and the market will adapt accordingly. That's why I suggest that if you wait for statistical proof, you'll have missed the boat, and the edge will have sailed.

Statistical proof is great for something like controlled medical studies, but essentially useless for sports betting where the environment is constantly changing. Rules change, players change, strategies change. Does anyone really expect to study results from the ATP or WTA and be able to have statistical confidence in a system that has been profitable in the past? I would hope not.

I think where the idea of statistical proof does have some merit in betting is when evaluating a tipster's record. Joseph Buchdahl wrote a book on this called "How To Find A Black Cat In a Coal Cellar". Well worth a read, but for those with shorter attention spans, or retired NFL players, this shorter article is also very interesting. It concludes:
However, until I see some significant sample of data that contradicts everything I have reported on here, I am prepared to stand by my assertion that almost all so-called tipsters are anything but, and that most of what is being sold represents nothing more than slick marketing in an attempt to attract customers to products that in fact are not what they claim to be. For the most part, that is not because the sellers are trying to defraud the buyers, but simply because the sellers haven't yet realised that luck is not the same thing as skill.
How to decide when the edge has gone is a tricky question. Where to draw the line is a personal decision. For me, it depends on the confidence I had in the strategy in the first place, and I suggested a few days back using a stop-loss while continuing to track results. Monitoring the ROI can be useful too, although since most sports have a relatively small number of bets in a season, I wouldn't put too much weight on a percentage based on less than 100 bets.

One example about confidence is the T-Bone System, which I've written about several times, and which has three components - Money Line, Run Line and Overs. Last season, in July, I wrote a post about the large profits from backing the Overs in these games. I wrote at the time:
Whilst both the Money Line and Run Line profits are steady enough in the last five seasons, the profitability of the Overs component is something new this season, and rather a mystery.
So I have far more confidence in the Money Line (profitable in 6 of the last 7 seasons) and Run Line (profitable six seasons in a row) part of this system than I do in the Overs which is basically flat over seven seasons. 

Hopefully some of you are playing this simple system this season. 
Eggmund returned with a comment on my Wall Street Journal Best Stock Award post from yesterday commenting:
Looks like an award for building a volatile portfolio, not one that will necessarily perform in the long run. Not a particularly meaningful award, apart from telling you which managers will give you the most exciting roller-coaster ride!
I wouldn't expect an index tracker to win this award even if eligible as they should track the market rather than massively out / under-perform it. That's not to criticise index trackers; they have a different purpose.
Not a particularly meaningful award at all, and Eggmund is quite correct that an Index Fund would never win an award over such a short and meaningless period of time. A return of 0.09% over ten years when 5.47% is the benchmark is frankly dreadful. And then there are the fees.   

Thursday 27 July 2017

And the No. 1 Stock Fund Is Not

Frequent readers will know my thoughts about passive Index funds versus actively managed funds, and my attention was drawn to a recent article in the Wall Street Journal proclaiming, and rather misleadingly:

And the No. 1 Stock Fund Is… Miller Opportunity Trust wins with a 48.55% gain for 12 months
That sounds quite impressive, but when you look a little deeper, it turns out that it's a bit like the end of season Most Improved Player Award, which is easier to win the worse you were the previous season.

You're still a crap player, but it's much easier to improve from a low starting point than from one of excellence. You may be Most Improved, but calling yourself No. 1 Player would be a stretch.

Going back over the past ten years, July 2007 to July 2017, and the Miller Opportunity Trust fund is up a total of 9.37%, which is less than 1% per year - 0.09% to be precise.

Contrast that with the S&P 500 benchmark index which is up a total of 70.27% over the same period, an annualised rate of 5.47%.

The "contest" seems a little flawed, in my opinion, an opportunity for undeserved awards and a few drinks to be handed out. Note that Index Funds are not eligible.
The quarterly Winners’ Circle contest is designed to identify which U.S. stock fund with at least $50 million in assets and a record of more than three years posted the best performance in the trailing 12 months. Index funds and exchange-traded funds don’t qualify because they aren’t actively managed

Brains, Rugby and Diamonds

Some of you, if you're not former NFL players, may recall a post I wrote in February 2016 about the NFL and my thoughts on the debilitating brain injuries that it was becoming apparent were related to the sport.
It's also become clear in recent years just how much damage the game is doing to players physically. It's brutal, with Chronic traumatic encephalopathy (CTE) a major issue that could yet see the game's popularity decline significantly (to be replaced by rugby perhaps?) and with thousands of other players suffering life-changing physical injuries. The NFL reportedly reached a settlement in 2013 with around 4,500 former players (or their estates) with chronic traumatic encephalopathy.
This week, the results of a study were published.
Dr. Ann McKee, a neuropathologist, has examined the brains of 202 deceased football players. A broad survey of her findings was published on Tuesday in The Journal of the American Medical Association.
Of the 202 players, 111 of them played in the N.F.L. — and 110 of those were found to have chronic traumatic encephalopathy, or C.T.E., the degenerative disease believed to be caused by repeated blows to the head.
The New York Times has an in depth article on the study here, while a recent article in the New York Daily News for those with shorter attention spans is included below - I'm not quite sure if the headline writer was trying to be funny with his use of "stunningly": 
Football on the brink: Stunningly scary news about the NFL and CTE
The evidence is now overwhelming: Football, the most powerful, popular and profitable sport in America, is hazardous to the health of those who play it.
A neuropathologist examined the brains of 111 deceased National Football League players. All but one turned out to have chronic traumatic encephalopathy, the neurological disease that causes depression, memory loss and dementia.
This was, it’s important to note, not a random sample. The brains were donated to science because players’ families suspected something was wrong.
But so high were the numbers, incidence of CTE would remain well above the norm even if every other dead one-time NFL player turned out to have a perfectly healthy brain.
We can’t unlearn this, not even with pre-season enthusiasm bubbling. A lifetime of playing football correlates strongly with lasting harm to the human brain. Barring major changes to the game, it’ll be hard to ever cheer the same way again.
The door might be opening for Rugby. I'll be in the US in September for the Newcastle Falcons v Saracens Premiership fixture, a much appreciated and belated Fathers Day gift from my kids, one of whom very conveniently lives in Philadelphia, where the game is to be played. I'll be the one in a Bath shirt. 

A previous visit to that fine city coincided with the Autumn Internationals last year, and admittedly an Irish Pub (Tir na Nog, known to at least one reader) isn't a random bar to perform a formal study, but there was a lot of interest in the back-to-back games that day. Several people I spoke to, I'm a friendly chap, had made the trip to Chicago a couple of weeks earlier, to watch Ireland defeat the All Blacks.

As the concluding paragraph in the Daily News article says, we can't unlearn the knowledge that hits and concussions in American Football are not amusing, and can no longer be casually dismissed with jokes along the lines of "he had his bell rung there". The consequences of these events are serious. 

Most sports inherently have some level of risk, but a sport where injuries are expected, and players are almost expected to cause injury to other players, is a brutal sport which needs to evolve or fade away.

The New York Times mentions that:
The N.F.L.’s top health and safety official has acknowledged a link between football and C.T.E., and the league has begun to steer children away from playing the sport in its regular form, encouraging safer tackling methods and promoting flag football.
If you've not yet seen the 2015 award winning film Concussion, which covers this subject matter, I recommend it.

In other NFL news, the hunt for a $150k diamond earring lost in a Georgia lake goes on...
As if losing the Lombardi Trophy by coughing up a 28-3 lead in the Super Bowl wasn't enough, Atlanta Falcons wide receiver Julio Jones lost a $150,000 earring on a jet ski this week.
Jones emerged from a ride on the motor-propelled personal watercraft on Lake Lanier in Georgia and noticed one of his massive diamond-stud earrings dislodged when he crashed into the water. Jones otherwise was unharmed during the joy ride.

"It was worth a little bit," Jones said of the earring in a television interview.
Jones' jeweler told WXIA-TV in Atlanta the gem was worth about $150,000. The 28-year-old All-Pro has earned $51.71 million since entering the NFL as the sixth overall pick in 2011. His 2017 base salary is $11.5 million. That's about $179,687.50 for every quarter of football over 16 regular-season games.

Wednesday 26 July 2017

ATP Tour Results 2015 to Date

I finally got around to looking at the ATP tour results going back to 2015, and the results by round are here:

Nothing to see here for the most part, but the consistency of favourites in Grand Slam semi-finals doesn't carry over into the lower quality tour events, with this round generating the worst ROI of all.

Backing the underdog in these games is a loss maker too, down 6.13 points at Pinnacle's prices, although at best this strategy would show a 1.85 point gain. 

In theory, backing all favourites at the best prices would have won you 19.83 points, representing an ROI of 0.28%, but that's a miserable return given the time required to follow such a 'system'.

The full results are here:

One thing that does stand out, which you should all know by now anyway, is what a difference just a 0.01 difference in the price achieved makes over a large number of bets.

It reminds me of the huge difference in returns from investing in low cost index funds and higher cost managed funds. It's easy to ignore a 0.25% difference in fees per year, but over 30 or 40 years it adds up to a significant amount of money. 

Dogs on Tour Redux

A few days ago, I wrote a post extolling the virtues of backing the underdog in the later round of WTA Singles events. Not for the first time in my life, validation and due diligence again confirmed the old chestnut that if something looks too good to be true, it probably is.

The problem in this case was that the raw data I used included prices on walkovers and early retirements, early in this case being prior to the completion of the first set, so returns from such "wins" were in fact null and void. The perils of publishing research findings before they have been peer reviewed. 

The updated results from all WTA events from 2015 to date are below:

Note that I have treated the Round Robin round of the end of season tournaments as Quarter-Finals. 

Quite a come down from the 6%+ ROI originally identified, but at least it ended up in the green.

In complete contrast with the Men in Grand Slams, (I've not yet looked at the ATP tour in full), Semi-Finals are hugely profitable for the underdog Women with an ROI of at least 23%.

While the favourite-longshot bias appears to be missing from the later rounds of the WTA tour, across all rounds, it's there. 

Tuesday 25 July 2017

Top Notch

Miguel Rodrigues ( @Adonis9898 and well worth following on Twitter) had a comment on my Men's Singles Grand Slam post from yesterday:

Cassini your blog articles are top notch without a doubt but I'm still very sceptical regarding this type of technical analysis mainly due to the fact that it seems to me very random and with technical analysis you will never now if the market adapted already in the current price.
This is not a criticism, just trying to understand how to check these two limitations with technical analysis, I guess for sample size you use p-ratio,but regarding knowing if the market has already adjusted I don't have any idea.Thank you, all the best
I appreciate the comment regarding the quality of my articles and completely agree that any observations need to be treated with a healthy dose of scepticism.

My goal with these things, whether it be football, tennis, baseball, american football, basketball or whatever, is to try and identify areas in the market where there appears to be a weakness, i.e. the prices are inefficient. I'm all too aware that past results are no guarantee of future results, indeed the expectation is that any weakness should soon be corrected by the market. 

It is why I long ago cautioned against waiting for statistical 'proof' of an edge before getting involved. It's a paradox that by the time an edge is proven, it probably no longer exists! 

As I've written before, markets change overnight. In my opinion, the trick is to identify a trend, and ride it to the end with sensible stakes. Ideally you add to your bank, move a trailing-stop up as profits grow and if the stop is breached, stop betting. 

Of course you can and should, still continue to monitor the system to confirm that the edge is gone, as I will do with the Bundeslayga system, which was a loser last season after many seasons of giving.

Specifically with the tennis findings in yesterday's post, my 'research' confirms that the favourite-longshot bias is very much alive and well in Men's Singles Grand Slams, and that blindly backing underdogs is akin to throwing your money away.
I was interested in looking at a few possibilities, one of which was to see if the First Round of these tournaments showed any weaknesses, but as the results above show, although the market tends to undervalue the favourite, it's a very slender advantage.

But here's an example of what I find interesting when looking at these things. 

If you dig a little deeper, you find that the First Round is a graveyard for favourites in the U.S. Open. Back First Round favourites in the first three Slam events each year, and historically (2013-2017) you would have been able to achieve an ROI between 2.6% and 4.6%. Will this hold in 2018? We'll see.  

Finally, James, possibly his real name, had some thoughts on poor Eadwig's early demise at age 19 or 20 - opinions differ: 
I would assume Eadwig died of exhaustion.
Quite possibly. The tale of young Eadwig being pried from his bed, and from between the arms of his “strumpet” and the strumpets’ mother, reminds me of a similar incident that befell me a few years ago.

I was in a 'lower end' pub chatting to a reasonably attractive lady who I was guessing was probably in her early 40s, based on appearance and from the fact that she had been talking about her daughter who was currently at university, and from the pictures she showed me, extremely attractive. 

After last orders was called, she asked me if I'd be interested in a 'Sportsman's Double', a term which at the time, coming from a sheltered upbringing and leading a quiet life, I had never heard of.

She explained what the term meant - a threesome with a mother and daughter, lest you not know - so of course, I was all over that.

We headed down the road to her place, and on arrival she opened the door and yelled up the stairs.

"Mum! Are you still awake?"

Monday 24 July 2017

Men Slams Redux

A fair portion of my weekend was spent revisiting the Tennis Spreadsheet, removing matches where there was either a Walkover or a retirement prior to the completion of the first set. 

For the men in Grand Slam (Singles) events, my suggestion that:

if you're betting on Men, stick to the favourites in Australia and France, and take the rest of the year off
still holds. 

Since 2013, the outcome of backing the Pinnacle favourite at these ten events is:
More selective price shoppers could theoretically have increased their ROIs by up to 4.5% and 5.6% respectively. 

For most of us, placing ~125 bets per Slam would be a daunting task, but betting on semi-finals (favourite) and finals (underdog) only across all Grand Slams is much more rewarding in terms of ROI, up between 10.90 points to 12.60 points from the 57 matches since 2013.

Women up next, as time permits. 

Friday 21 July 2017

Bastad Walkovers and Retirements

Don Pablo asked:

Is this article based on the analysis of singles matches only or both singles, doubles and mixed doubles matches. Clarification will be much appreciated
I didn't realise anyone bet on doubles matches, and I don't know where historical odds for these matches could be found anyway, so to clarify the results are for Singles matches only.

Brian of Betting Tools fame and fortune helped out with the walkover question writing:
Yes most require the 1st set to be completed, others the full match. When I checked at the start of the year there were 2 'first ball served' bookies who would pay out if the match had started but just checked and they both now require the first set to be completed. As far as I know there isn't anyone who pays out for a walkover.
This post on his website gives more details on rules by bookmaker, but as Brian mentions above, rules can change so don't rely on this.

Next time I have a week to spare, I'll run the numbers again excluding Walkovers and First Set retirements. 

Unfortunately, with more than half of the retirements / walkovers favouring the underdog, (for 2015 and 2016), this system isn't as good as it might have first appeared. 

Losing the likes of 14.8 and 13.0 winners (Rome and Bastad 2015) and a green system can soon go red. 

Bastad indeed!

Dogs on Tour

I mentioned yesterday that:

...if the Women's game is your preference, stick to underdogs from the fourth round onwards.
I decided that it might be worth taking a look at how this strategy has played out this season across all tournaments on the Sony Ericsson WTA Women's Tour. 

The Fourth Round in Grand Slams is the Round of 16, or Eighth-final, for non-slam events, and after 34 total tournaments, backing the underdog would have returned a profit of between 25.32 and 36.16 points from 501 bets, and ROI in the 5% to 7.2% range. 

On the face of it, not bad, but when we consider the returns from Grand Slams alone I mentioned yesterday, it's clear that this is a losing strategy across the 31 non-slam events.

I did learn something through this little exercise, which is that the Women have three tiers of event - Grand Slam, Premier and International, and in the 19 International Tournaments so far, this strategy is up between 27.34 and 34.37 points. 

Incidentally, on Hard surface tournaments, the strategy is up between 46.66 and 53.11 points most of that on Outdoor courts.

So far so good, but the season is 60 tournaments long, so I went back to 2016. Backing the underdog in the later rounds (Round of 16 to Final) would have won between 47.50 and 74.52 points from 876 bets, a similar ROI to that so far in 2017.

2015?, I hear you ask. It just keeps getting better. Only 59 tournaments that year, but the strategy is up between 60.71 and 85.93 points from 837 bets, an even higher ROI than 2016 and 2017.

So from 2015 to date, backing underdogs in the last 16 or later in every WTA event would have won between 133.53 and 196.61 points from 2,214 bets, an ROI of between 6% and 8.9%

This is in no way a criticism of them, you can't beat free and they are very useful, but be careful if you decide to use the spreadsheets yourself, as there are several errors in them. Typically the Maximum isn't the maximum, and other times the favourite and underdog are incorrect, but a simple validation will catch these and manually correcting them isn't difficult.

I've also noticed that while there are not hat many, walkovers are included in the sheets which I should probably adjust for. Perhaps someone more familiar with tennis betting than myself can confirm that books generally only pay out on completion of the first set.  

Thursday 20 July 2017

Wimbledon Favourites (W) Buck the Trend

Following on naturally from my previous post, for the Ladies Singles, Wimbledon 2017 was a different story where backing the favourite in every game was a very profitable strategy, up 13.40 points, an ROI of 11%.

Here are the results for backing Ladies Grand Slam favourites this year at Pinnacle's prices:

Not that I am complaining, but I did find a couple of errors in Joseph Buchdahl's Mens Wimbledon 2016 data.

In the Final, I'm pretty sure that Andy Murray was not a best priced 4.36 to win, and similarly I don't think Grigor Dimitrov was a 1.75 favourite with Pinnacle to beat Stevie Johnson in their 3rd Round match.

The previous post has been updated to correct this palpable error.

I'll update the numbers after the US Open completes the 2017 Grand Slam season, but it's clear that since 2013, if you're betting on Men, stick to the favourites in Australia and France, and take the rest of the year off, and if the Women's game is your preference, stick to underdogs from the fourth round onwards. 

Such a strategy would have profited between 34.11 and 58.47 points (Men) and between 37.10 and 53.75 points (Women). 

Not a great return for the effort involved on the men's side, and frankly not my cup of tea, but for the women, 15 matches a tournament is a manageable number of bets, and since 2013 (19 tournaments) would have an ROI of between 13% and 18.9% (37.10 to 53.75 points).

Wednesday 19 July 2017

Favourites (M) Slammed

Wimbledon 2017 ended a run of six Men's Grand Slam tournaments where backing the favourite in every game was a profitable strategy.

Here are the results for backing Grand Slam favourites this year at Pinnacle's prices:

and for the 2016 season:
Conventional wisdom for tennis betting is that in line with the favourite-longshot bias, backing the favourite will result in you losing your money slower than you would by backing the outsider. 

Backing the outsider would have been profitable in Australia this year, simply because of two long-priced winners - Istomin beat Djokovic at a best priced 41.0 and Zverev beat Murray at a top price of 28.0.  

In the eleven Grand Slams (Men) since 2015, an underdog backer at Pinnacle's prices would have lost 181.22 points, 16.47 per tournament, while a favourite backer would be up 14.24 points, 1.29 per tournament.

If you believe in unicorns, Santa Claus, angels or gods, then by backing at the best priced books, your losses would be reduced to 108.02 points on underdogs, and profits boosted to 35.24 points on the favourites.  

Tuesday 18 July 2017

Patsies and Strumpets

Eggmund, possibly not his real name, commented on my Physics Presumptions post:

Hello, nice blog.
I used some of the principles of Statistical Mechanics that I picked up from my Physics degree when writing my Cricket model. It could be that this is the sort of thing referred to as "Physics Presumptions".
A very charitable explanation, and one that in my opinion, isn't supported by the evidence when you consider the individual's writing in more detail. 

Here's his Pinned Tweet:
It's hard to view this nonsense as the product of an educated mind, from an individual who might be into "particle physics" or "Statistical Mechanics". 

To me, it's a nonsensical rambling with the end goal of selling a worthless tipster service to gullible individuals by adding faux intellectual gravitas to the subject. 

Eggmund, (if there was never a King Eggmund** back in the day, there should have been), is clearly a much nicer and more intelligent person than myself, and he continues: 
By the way, I like your principle of Bet-And-Forget. It nicely expressed what I've been looking for for a while as gambling time competes with family time! I'm now working on how I can build positions purely during intervals in test matches, without having to follow games live. Thank you for the tip.
The only person who benefits from betting in-play these days is someone trading the game with the advantage of being court-side / green-side / pitch-side / table-side / etc. If you do not have this edge, and most of us don't, Bet-and-Forget is the only strategy that makes any sense.

It's gratifying to see that this message is finally getting through. Trading sports sounds dangerously simple, an easy way to riches, and back in the early days of the concept it was quite possible to find a trading edge, but the markets have evolved.

One more time - If you are trading in-play, you are competing against others with more information than yourself.

Here are my thoughts from a few weeks back:
You are not going to obtain any information from your TV that hasn't already been seen, evaluated, and acted upon, by others before you.
If you, and I think quite logically you can, assume that these full-timers are not donating their money to the market each day, i.e. they are net winners, how can you, sitting at home, seriously think that you can overcome this disadvantage over the long-term and make a profit?

It's a zero sum game, and as the Warren Buffett quote from yesterday puts it:
"If you've been playing poker for half an hour and you still don't know who the patsy is, you're the patsy."
No guide in the world is going to be able to help you overcome this disadvantage. You are always working with stale information, which would be a level playing field if everyone else was too, but you're competing in markets where others have more current information than you.

It's frankly delusional to think you can be competitive under such conditions.
** I checked - no Eggmund, but we did have a couple of Edmunds and an Eadwig (955 - 959) with an interesting background:
The eldest son of Edmund I, Eadwig was about 16 when he was crowned king at Kingston-upon-Thames in southeast London. Legend has it that his coronation had to be delayed to allow Bishop Dunstan to prise Eadwig from his bed, and from between the arms of his “strumpet” and the strumpets’ mother. Perhaps unimpressed by the interruption, Eadwig had Dunstan exiled to France. Eadwig died in Gloucester when he was just 20, the circumstances of his death are not recorded.

Saturday 15 July 2017

Physics Presumptions

There are worse ways of passing a Saturday night than doing research on behalf of @Statsbet, who prompted me to compare the League 2 Away returns discussed here, only using the Pinnacle odds scraped several hours prior to kick-off rather than the Pinnacle Closing Prices.

For the five seasons where the data is available, the results are as above. Closing prices beat the earlier prices (let's be clear that these are not "opening" prices), but over the past two seasons betting earlier has been the optimal strategy, possibly because someone revealed this simple system and the money consequently floods in towards kick-off, driving the price down. Or possibly not.

If you follow @Statsbet on Twitter, you'll find that he crosses paths and swords with some strange characters out there. 

One such individual is setting up a tipping service for next season, the cost:
Will be £50 per Calendar month for model data covering 6 leagues this season. Only accepting 10 clients to begin.
Only £50 a month! This sounded like a bargain, except that no verifiable results are to be found, and when asked how publicly available data could provide him an edge, the response was a nonsensical:
My interest was short-lived. If anyone knows what "physics presumptions" means, please let me know. My money, and I hope all of yours, shall also remain private. 
Call me old fashioned, but when someone admits to having no money, and is looking at betting on in-play football in China, it sends a message of cluelessnes and desperation rather than one of success. A few minutes later:
Imagine my surprise.

Closing Lines

Rodolfo commented: 

In recent weeks Joseph Buchdahl has published several articles on the importance of beating the closing odds. Do you consider beating the closing odds as an important factor whether particular betting strategy is profitable or not? Have you ever recorded closing odds yourself on a regular basis?
Long-time readers of this blog will know that I am a firm believer in the importance of beating the closing odds, which is why I became so excited when Joseph added Pinnacle's Closing Prices to his football sheets dating back to the 2012-13 football season.

As Joseph explains:
Closing odds reflect the largest amount of information about matches, and the maximum number of opinions being expressed through wagering on that information, and hence are most likely to be the most efficient.
As a part-timer, I have never had the time to record closing odds myself, but fortunately for all of us, Joseph has now filled the gaping hole in this area. 
Readers will know that one of my favourite sports for betting is baseball, and several years ago saw this quote on a forum discussion about closing prices:
In all free markets - pricing efficiency is generally enhanced with the addition of market participants and incremental information over time. The MLB wagering market is no exception. The closing line is generally a sharper number than the opening line. The fact that a winning MLB handicapper beats the closer more often than not is not the reason he's a winning handicapper but rather a reflection of his being a winning handicapper. He has the ability to identify the smart side of the early (weaker) number. More often than not, his good judgment will be confirmed by the subsequent line movement. His early wager will thus, more often than not, have a value edge vis a vis the ultimate closing number. It's as simple as that.
Anyone who is profitable in MLB over more than a half season without beating the closing price more often than not - who thinks he is good - is mistaking good luck for good play. And to any of you who believe that beating the closer is a meaningless or overrated measure of a good handicapper - I can only say you are wrong - and assure you that the Las Vegas books would agree with me.
So the importance of beating the closing line has been clear to me for several years and is why my MLB, NFL, NBA systems etc. all use the closing prices. In reality of course, it's impractical to place all bets at these closing prices, (sometimes you'll get lucky, other times not so lucky) but it's always the benchmark to be used when evaluating a system. It also allows others to easily verify the results. 

One of the many problems with measuring a football tipster's edge is that the prices they claim are often, to put it favourably, somewhat arbitrary. Prices move throughout the days leading up to a match, reacting to new information and money coming in to the markets. This allows someone to cherry pick the prices they record their results against. 

It is why my own selections and results were recorded using Pinnacle's prices wherever possible. This consistency and transparency was a welcome improvement to the opaqueness of others, but three seasons ago, was still less than perfect. 

Prices were scraped, at best several hours, and at worst, several days before kick-off, thus the role of luck played a bigger part than it should - for example, the late news that a star player would miss the game wasn't reflected in the odds used. The most extreme example is the scraping of a price on a Friday afternoon for a game on Monday night. Clearly less than ideal.

The long overdue addition of Closing Prices for football means that everyone now has a standard to measure their performance against. Be wary of anyone who doesn't report their results against this benchmark. 

A Closing Line for the Over / Under markets would be a nice addition too if Joseph is reading this.

Finally, Football Investor Stewboss clarified things, writing:
Sorry if I got the wrong end of the stick re your draws betting. Perhaps you should have replied to my last tweet
With everything else that's going on in my life right now, correcting a minor misunderstanding by one person on Twitter wasn't particularly high on my list of priorities. It became more important when repeated in a comment, but we're all on the same page now.

Friday 14 July 2017

A Slightly Better Bettor

Stewboss commented on the Filter Bursting post with:

"Secrets are secrets. An edge shared is still an edge halved. If I give or sell you a secret then it's no longer a secret."

That would be true if indeed you were placing the bets yourself but as you've already informed me that you haven't I don't see why you're so keen to keep it a secret. I'm not that bothered personally as I have created my own version with slightly better results than yours :-)

Maybe you could introduce an paywall version of your blog for those in the know so to speak !!
I'm not quite sure where Stewboss got the idea from that I wasn't using this system myself. 

In response to Stewboss's initial enquiry about my Draws, I did say that I hadn't updated my own ratings in almost two years.

This was a very time consuming activity whose rewards were not justifying the additional time over a more basic single filter system.

With regard to the less time consuming Draw system, I stated that "it was a loser last season anyway!", but unfortunately for my wallet, that didn't mean that I hadn't followed the system.

Anyway, a minor misunderstanding, and good for Stewboss that he has a Draw System with improved results over mine, although some clarification on 'slightly better' is needed.

Are we talking ROI% or points?

Looking at the past five EPL seasons (i.e. those where the Pinnacle Closing Price is available), the highest ROI for backing the draw with one filter is 150.4%. Unfortunately this was from just seven selections, which across five seasons isn't too useful.

In terms of points, the best single filter for backing the draw returns a profit of 82.65 points (from 710 bets), while the best ROI from a filter generating an average of at least one bet per round (i.e. 38+ a season) is 21.5%, from 294 selections.

Filter Bursting

Jameson wasn't the first to ask:

hi. what is the second filter you applied for draws? 1st is ip 25+, and second?
Unfortunately, as I told Stewboss, since this filter has added value in each of the five EPL seasons for which we have Pinnacle Closing price data available, the filter will remain proprietary. A great man once told me:
Secrets are secrets. An edge shared is still an edge halved. If I give or sell you a secret then it's no longer a secret.
How valuable is such a 'secret' though? 

Some of you undoubtedly noticed that the number of Draws in last season's Serie A was the lowest since 1995-96. Of the 50 top flight seasons in England, France, Germany, Italy and Spain during the last ten years, only four have been lower, and two of those were in the traditionally higher scoring Bundesliga where you'd expect fewer draws. 
Unsurprisingly backing the Draw in every Serie A match last season would have been costly as usual, but the benchmark (matches where the Draw probability is 0.25 or greater) would have again been improved by applying the filter, reducing a loss of 35.01 points to a loss of just 8.99 points. 
It was the same story across Europe last season, with the filter adding a total of 133.54 points to the benchmark:
An ROI% of -1.61% isn't usually something that sets the pulse racing, but it's a whole lot better than the -12.37% on the benchmark.

One swallow doesn't make a season though, and one season doesn't make a golden goose, so I looked back a couple more seasons to see if the pattern held. 
As you can see, it did, turning a benchmark loss of nearly 150 points into a profit of over 100 points. 

For the five seasons for which we have Pinnacle's Closing prices, the results are here sorted by league / season Draw percentage:
While the correlation between the Draw and returns is obvious, the (usually) added value of the filter isn't apparently influenced by the Draw percentage.  

Sunday 9 July 2017

Drawing Blind

Football Investor Stewboss asked me via Twitter "will you be revisiting your Draws system on the blog anytime soon?"

I think the Draws System he refers to is the one I mentioned early last season in this post.

Back then I mentioned that:

Backing the draw in the (conveniently exactly) 1,000 matches where the implied probability of the Draw was 0.25 or greater at kick-off would have boosted your account by 49.22** points, and you can all work out the ROI% on that.
I also mentioned a simple additional filter which can be applied to both reduce the volatility and increase the profits, and published the table below showing the results of blindly backing the Draw in all English Premier League matches, applying the Draw filter (IP 0.25+) and the second filter. 
Unfortunately for Draw backers, last season saw the second fewest Draws in the last eleven seasons, and the third fewest in the top English division in the last 30 seasons.
It's hardly a surprise then, that the numbers for last season reflected this. 

Blindly backing the Draw in every match would have cost you 38.92 points, using the draw filter would have lost 37.08 points, but by applying the second filter, the losses are reduced to just 4.51 points, which in the circumstances, almost seems like a win! A five year ROI of 12.25% for a simple system is excellent, and unless Draws are heading into a long-term decline which seems unlikely, the profits will soon be back. 
As I mentioned to Stewboss, last season was very much a season for Home teams, not just in the EPL but across the top leagues in Europe where the percentages were strangely consistent everywhere, Homes up, Draws down (if you'll pardon the expression): 
That Homes in the EPL would leap to 49.21% the season after the lowest percentage for English top division homes (41.32%) since the Second World War, makes it all the more surprising.  

For the record, blindly backing the Home win in the top five leagues in 2016-17 would have won you 97.80 points, an ROI of 5.36%

Eliminate the longshots with an Implied Probability less than 0.1 and the ROI climbs to 7.3% (130.31 points from 1,781 selections). 

** All calculations use Pinnacle's Closing Odds courtesy of Jospeh Buchdahl's excellent Football Data website.