NFL, Rest and Heading South

Hopefully some of you ignored the 'Andy Reid and Unders' advice out there last week, and followed me on the Overs this past weekend in the NFL Championship games:

Overs do have a 20-13-1 advantage

Some of you may have seen the trend that since Andy Reid has been the head coach of the Chiefs, Unders is 37-19-4 in home games. While this is true, in playoff games this record is an insignificant 3-2.

So the Kansas City Chiefs will play the San Francisco 49ers in the Superbowl, and I shall be in Cape Town that weekend so you're on your own looking for an edge in this one, and good luck finding one with the game one on the most analysed in all of sports. 

If the market does have an inefficiency it would appear to be that the favourite is over-rated, (6-12 ATS in Superbowls since 2001) which makes sense given the public and 'square' money coming in to add an interest to the game. 

In games where the line is greater than a field goal, the 'dog is 10-2, but unfortunately the line looks like it'll be close to 1.5 with the Chiefs favourites.

I'd have expected Overs to be 'over'-backed also, but 'over'all these are 9-9 over the small sample size. However when the line is relatively small, i.e. fewer than 4.5 points, Overs has a 7-3 record. 

And that will be it for the NFL 2019 season, one that flew by and was again profitable for followers of the Small Road 'Dog System. I'll try to remember to do a summary when I return from South Africa in mid-February.

This will be my last post until then. 

I don't have time to go deep into the topic right now, but I have seen some recent comments about the importance of 'rest' in some sports, but in my opinion the impact of this is pretty well understood and factored in. 

I've written on this topic before, and where someone might want to focus their attention is where the rest might not be as straightforward as simply looking at the number of days since the last game. 

For example, a night game that went into double overtime followed by a day game on the road in a different time zone still counts as zero rest, same as the opponent who is at home following a blowout day game in which the starters were rested for much of the second half. Surely few would agree that the "rest" parameter for both teams is really the same, and it can be useful to consider these details.

Something to think about, but I have a plane to catch for my first, and long overdue, visit to the southern hemisphere and some cricket matches.

I shall return.    

Tesla and Totals

Last week, I cautioned against blindly backing the the Overs in NFL Divisional Playoff games and in the end they split 2-2. 

As for the apparent value for Overs, I'd be wary. We're dealing with a small sample again, and while Overs has a 37-31 record overall, most of that advantage is in games where the line is 12 or higher, and none of this weekend's four games are close to that.

When the total is 48 or higher, the Overs is now 17-9 with the one qualifier (Kansas City Chiefs v Houston Texans) easily covering by 31 points. The win was secured by half-time, and the Chiefs made the 51 points on their own.  

Road Teams in this round getting 7 points or more tend to have an edge, but that didn't work out this weekend with just one winner form the three bets. With a 24 point lead at the end of the first quarter, the Houston Texans were looking good but the Chiefs came back strongly. 

The totals are currently set at 45 for the Chiefs v Tennessee Titans and 52 for the San Francisco 49ers v Green Bay Packers. 

So onto the Championship Round next week and there's half the data we have for the previous two weekends, i.e. not a lot. Road Teams are 16-18 while Overs do have a 20-13-1 advantage

Some of you may have seen the trend that since Andy Reid has been the head coach of the Chiefs, Unders is 37-19-4 in home games. While this is true, in playoff games this record is an insignificant 3-2.  

Neanderthal's blog has an interesting post on the subject of backing the Under in the NBA, something this blog looked at less than a week ago. His numbers are worth comparing with what I have found, and for those of you interested in the College version of the game, there's a little secret given away.

Some of you may recall my recommendation of Tesla shares from back in 2018, when they were trading in the low 300s, and while I doubt that anyone would have followed me on it, nor should you without doing your own research, the stock is certainly flying high right now:

Less than a month ago, Tesla were in the low 400s. 

As the short-sellers get driven out by forced covering and interest costs, the price could go even higher. A one day gain of close to 10% helped the spreadsheet last night, but didn't do much to support the "efficient market" hypothesis.

With parallels to betting markets, Warren Buffett's succinct observations on this topic (EMH) are appropriate:

Observing correctly that the market was frequently efficient, they [academics, many investment professionals and corporate managers] went on to conclude incorrectly that it was always efficient. The difference between these propositions is night and day.

Kyle Lowry - 9.1.15

There was a 'trend' highlighted on Twitter yesterday, which was that, and I kid you not:

Since Jan 9, 2015, in games where the Toronto Raptors are favourite, coming off a loss when they were favourite, and when more than half of Kyle Lowry's made field goals were 3 pointers.

The 'trend' was that of the 17 games since that memorable January day of 2015 (no, me neither), the Unders had a 16-0-1 record.

As often happens with these 'trends', the act of publishing it is all that is needed to doom it, and the game last night (Raptors @ Charlotte Hornets) went comfortably Over.

The thing is, such 'trends' are merely curiosities, the result of some presumably time-consuming data mining. 

Maybe these things are interesting to some, but as indicators of where a market offers value, they are dangerously useless.

Of course nothing happened in Kyle Lowry's life on January 9, 2015 whereby the relationship between his two and three point baskets suddenly took on a mystical importance.

Look at enough combinations of data and of course you will find examples like these, but if there is no rationale behind them, they are worthless. Not to mention that checking a database daily for five years and having just 17 selections probably isn't the best use of your time. 

No one on the planet is looking to back Overs "in games where the Toronto Raptors are favourite, coming off a loss when they were favourite, and when more than half of Kyle Lowry's made field goals were 3 pointers" and thus pushing the value to Unders.

There's another one tonight if anyone is interested:

Since December 2019, a road team that is off a win in which they were not winning at the end of the third quarter and they allowed fewer than 28 points in the fourth. It is 20-0 ATS and it is active tonight!

This one is actually slightly interesting because it's based on a solid idea - that there might be some carryover when a team finishes strongly and wins. 

However, I'd expect the value to be on the side of opposing these teams, since recency is such a strong bias. I'm not interested in the number of points that the opposition scored in that final quarter, nor do I believe that the night of November 30th was momentous. That's just fluff to make the 'trend' look more glamorous. 

So as I do, I took a look at teams who came from trailing after three quarters to winning the game and here's what I found going back to the 1995 season in regular and playoff games:

Over the last one and a half seasons, backing road favourites in this position (regular season) has a 31-21 (59.6%) record.

Going Under In The NBA

I've spent a little more time looking at the free football data and while I was focused on Pinnacle's numbers, it seems rude to ignore those of Bet365. 

Having done so, I can see why I pretty much ignore other books. Based on 3306 matches where we have data from Bet365 and Pinnacle for both the Money Line and the Under / Over 2.5 Goal markets, the average over-round (Money Line) for Pinnacle is 102.4% compared with Bet365's average of 106.7% while for the Over / Under market the numbers are 102.8% and 105.8% respectively.

If you were stupid enough to back the Home, Draw, Away, Under and Over in every game, I hope you'd have at least saved yourself 622.43 units by betting with Pinnacle!

Backing the Draw at the better of the two prices in every match would have resulted in just about breaking even, though not quite, with a loss of 29.49 units, or slightly less than 1%. 

As with financial investing, the impact of commission or fees on your transactions should never be an after-thought. The impact of higher fees on actively managed funds over time has been covered in this blog previously, and one big reason why investing in low fee index tracking funds is my preference, but the same logic applies to betting, with the added complication that the "best" prices might not always be an option for you, in which case you have to go with the best prices available to you.

Polish NBA fan Wojciech Malinowski tweeted:

I'm not sure if Pinnacle operate in Poland or whether Betfair allow bets from there, and if so at what rate of commission, but for sure, overcoming a 12% tax would be quite a challenge to say the least.

Ben sent me this suggestion a few days ago, and rather rudely I don't think I ever said thank you as I was away at the time, but hopefully he will accept a late thank you here and not mind me sharing this personal recommendation more widely:

Have you looked into using a betting brokerage platform like Sportmarket to place your wagers (avoiding the Betfair premium charges)?

I’ve been using the company for a bit over a year now and have withdrawn with ease each time.

I regularly beat the Betfair starting price (inclusive of commission), simply due to the availability of multiple asian books.

Personally I have no experience of this platform, but Ben is a quality individual and I have no reason not to trust his opinion here.

Regarding the second part of Wojciech's comment on the NBA Unders, and the challenge right now is that finding Unders is a little like trying to find a stock to short in a soaring bull market.

They are out there, but a rising tide lifts all boats as the expression goes, so caution is needed. As a refresher for any new readers out there, point totals in the NBA have increased quite dramatically since the 2012-13 season. It's been covered in this blog for some time, but here is an interesting article from this season with tables to show the changes:

The 2012-13 season, or seven years ago, is when the league truly started exploiting the math and realizing they could reallocate some of the hardest field goals to convert into jump-shots with a greater reward (three-pointers).

Sports and consequently sports markets do evolve, even if it is impossible to prove to the satisfaction of a statistician, but then:

Arguing with a statistician is a lot like wrestling with a pig. After a few hours you begin to realise the pig likes it.

To find early signs of changes, it is important to keep tracking key metrics in games. 

If you see the average number of possessions changing, the likely effect is a corresponding change in point totals. 

If you see the number of three-point shots being taken is increasing, likewise. 

Are all teams changing their tactics the same way though? 

Fortunately (from an investing perspective) not. Three point attempts this season range from 44.3 per game (Houston Rockets) to 27.4 (San Antonio Spurs), while possessions per game range 104.4 (Milwaukee Bucks) to 97.1 (Charlotte Hornets).

Not coincidentally, the Houston Rockets lead the league in points followed by the Milwaukee Bucks, while the Charlotte Hornets languish in 28th place (out of 30 teams).

I'm getting slightly away from the original question, but the point I'm trying to make is that any evolution isn't likely to be taking place at the same pace across the league, and with teams playing in conferences, changes may be somewhat localised. 

So, is there value to be found backing Unders when the total is set low? The bias that is in play here is that if the total is set low, instinctively less-informed punters will see value on the Over.

What is a 'low' total? Because this sport is changing so fast at the moment, there is no mean total, so I start with looking back three seasons and the 211.2 number. 

Unders when the total is set below 211 over the two and and a bit seasons since hit at 56.3%. This increases to 57.2% in games between Western Conference teams, I suspect because the West is known for being higher scoring.

Probably the most active bias in sports betting is that of recency and in games between teams where both are coming off an Under, the win percentage goes up to 59.5%.

I'm not sure I like the name 'Anti-Beast' for a system though. 'Teddy Bear' perhaps, but the answer to the question is yes, value is there on lower point totals. At least for now. 

EPL Draw - Over Consideration

The NFL play-offs get underway today with the Wild Card games where historically the value is on Unders. Only twice in the last fifteen seasons has Overs 'won' more than two of the four games, the last time being the 2011 season. Of the other thirteen, three were split for an overall 40-27-1 record.

I hope a few of you were able to make some money on the Wild Card games this weekend, with all four matches going Under, the bet recommended above. 

This is the second sweep on Unders since 2012, and after the league reörganised in 2002, the Under is now 44-27-1. Tuck that thought away for this time next year. I also pointed out that:

Road 'Dogs are generally under-rated at this stage also, with a 28-22-2 record ATS, and in the last two season are 7-0-1.

Not perfect on this one, (Buffalo Bills missed out on making it so by 1/2 a point) but I'll take two out of three winners any day, and overall this bet is now 30-23-2 over the same period. The Seattle Seahawks were road favourites, but the record on such teams was an inconclusive 7-6-2 and as an Eagles fan, it would have been tough to back against them anyway.

Onto the Divisional Round next week where the value play tends to be the Overs, with Road teams continuing to do well ATS. Regarding the value on Road teams, I suspect that the bias at play here is that the Home team is rested in these games after a bye week, and expectations for them to do well are set unrealistically high.

Home teams do win the game 69% of the time, but ATS they are just 30-37-1. Road teams from the Eastern Time Zone have a 23-11 record, but for the first time ever (well, since 2001), there is not an Eastern Time Zone team on the road.

As for the apparent value for Overs, I'd be wary. We're dealing with a small sample again, and while Overs has a 37-31 record overall, most of that advantage is in games where the line is 12 or higher, and none of this weekend's four games are close to that.

I took a look at the data A Lucky A Day linked me too for the EPL Draw, and it has Money Line data going back to the 2007-8 season, 4695 matches and if you had backed the Draw in each one, you'd have an ROI of -3.9%.  

Ignoring the matches where there is no Pinnacle price for the O/U 2.5 market (and remember, these prices are all opening prices, so this exercise is out of curiosity rather than to 'prove' anything) we have 3311 matches, and if you had backed the Draw in all of these, your ROI would have been -1.39%. 

You really have to work quite hard to lose money backing the Draw, because by simply ignoring matches where the Draw is priced at 4.0 or higher, you are into profit, albeit by just 0.04%, but of course, readers will know there are other ways to eliminate losers, namely ignore games where one side is odds-on.

Now the ROI is 5.7%, with profits of 85.16 units from 1497 matches which might get your attention, although not that of everyone if this comment from the Betfair Forum is to be taken seriously (hint: it isn't):

i devised a system returning about 20% roi which is decent but not worth the time and effort that's involved

Good grief. Some people are clueless, this individual in more ways than one, but that's a good thing when using an Exchange!

Now it gets interesting. There are 229 matches where the Under and Over prices were both odds-on. Avoiding backing the Draw in these matches and you'd have boosted your return to 9.4%.

Which leaves 935 matches where Unders opened as the clear favourite, and 333 where Overs was clear favourite.

Now it gets very interesting. One might expect the "Under Clear Fav" row to generate more profit, but as you can see from the table below, this is not the case. 70% of the profits are coming from 26% of the matches. 

Pareto anyone?

Not only do these matches generate a higher percentage of Draws, but the average Draw price is also higher. 

While the percentages of matches resulting in 0:0 and 1:1 are close whether Under of Over is favoured, (and both above the long-term averages for these scores - top row below), the number of Draws of 2:2 and higher is greatly increased when goals are expected. 

It's important to remember that this data set uses the opening Pinnacle prices on the Under / Over market, prices which may well change significantly in the days prior to kick-off, and that the sub-set of matches already excludes games where one team is odds-on or the Draw is 4.0 or greater.

In these games, which in the EPL are already known to be profitable when backing the Draw, using the Under price isn't helpful. While still profitable, they are actually bringing down the ROI.

These are interesting numbers to keep an eye on as the data for Pinnacle's Closing prices from Joseph's site accumulate.

With only half a season of closing U/O data from Pinnacle, the loss is currently 11.32 units from 37 matches.

I mentioned the cost of the closing price data in my last post, which should make you appreciate the access to Joseph's free data all the more. If anyone has this data and wants to check the observations above, I'm sure many Draw lovers would be very interested in the findings. 

Change Is Constant, Mean Not So Much

"The only constant in life is change" - Heraclitus

By some distance, although admittedly with no competition, yesterday's post is already the most popular of the year, prompting comments in abundance on Twitter.

Mel (Scientia Trader) does indeed appear to have vanished from the face of the earth, with Dionysios confirming that:

Indeed, hopefully the latter. Unfortunately for Mel, the laws of probability do not suspend themselves just because you want them to, and the claim of a 50% to 60% strike rate being sustainable at a price of 3.8 (implied probability 0.26) was always quite ludicrous. Hopefully he is alive and well, and gainfully employed and didn't lose anything more than his pride. Of course, it is always possible that his huge edge was genuine, and that he is now retired and living on a private island somewhere. Nah. 

A Lucky A Day sent me some links to data for the Draw and Under prices, with the free version being the less useful (but nevertheless interesting) opening prices from both bet365 and Pinnacle. There's about 210,000 rows of data so I may be gone a while!

The closing prices come at rather a high cost, and I'm not sure senior management here, still seething after seeing my 2019 alcohol expenses, will be approving it.

In addition to being very helpful, Mr Lucky did comment that:

Personally I do think draws get overlooked and inefficiencies could last a long time!

Agreed, and the Draw has served me well over the years with thanks due to Derek McGovern for planting the seed in my brain back in 1999.

They also served many readers well when I shared the XX Draw selections for three seasons in the last decade:

Not a huge return for the effort, but For comparison, backing the Draw blindly in every game in those leagues for the three seasons would have lost you 5.8%. 

In some ways it's a shame I had to discontinue the spreadsheet, as it was based on the idea of expected goals before xG was even a term, but as I've mentioned before, it took several hours a week to make all the updates and a promotion at work meant that was no longer a viable proposition. For most of us, time is a precious commodity and as the cost of spending hours watching a sport in-play waiting for an entry point, so there is a cost to spending several hours a week updating the numbers for ~100 clubs.

Graeme Dand back in 2014 had this to say on the Draw:

I really buy into the idea that few punters back draws and they are more interested in backing a team to win (same idea as why no one backs 0-0 when watching a game as they want to see goals!)

Another expert who saw the potential for value in the Draw (and Under for that matter) was Daily25, who had this to say back in 2012:

I love the "in the right circumstances" qualifier, (aren't all bets profitable "in the right circumstances?") but a quick look at the free data would suggest the Under / Draw relationship I mentioned yesterday might have some merit. 

The Premier League data isn't quite current, with the latest matches from early December, but they go back to the 2010-11 season which is a fair way.

Stripping out the matches where one club is odds-on or the Draw is priced at 4.0 or greater, backing the Draw in matches where the Under is odds-on produce the following results:

I may need to change the wording from "odds-on" to "favourite" but more to come on this, and thank you to A Lucky A Day for the pointer.

Then there was this comment from Joseph, a little passive-aggressive in tone perhaps, but Joseph is more into the theory side of betting than the practical side, so I'll assume positive intent:

The problem with talking about a regression to the mean when it comes to sports and betting, or at least my technical analysis based form of betting, is that there is no specific and invariable mean, because both the sports themselves, and their related betting markets are constantly changing. 

In sports for example, from 1888-1892, the average number of goals per game in the top flight of English football was 4,37, and the percentage of matches ending in a Draw was 14.5%. Is this the mean to which the number of goals is expected to return to?

As mentioned many times previously, sports change over time. Rules are updated and scoring becomes easier or harder. Look at the impact of the 1925 changes to the offside rule in football. Points for events are changed (e.g. Rugby and NFL). Strategies change, e.g, the higher scoring seen in the NBA since 2012. Divisions, conferences and schedules are rearranged. The list is long.

The net effect of this is that data from one season often cannot be usefully compared with another season and the idea of numbers regressing to a mean is nonsense. Values are not constants.

Similarly with the betting markets that accompany these sports. For one example, one need only look at the football markets from Joseph's own website from 2000-01 where the over-round (William Hill) averaged 112.54%. This season the average (Pinnacle) is 102.77%, which marks a huge difference and you can't simply compare the results of a strategy without recognising this difference.

Markets also have to change because the underlying events change. I've written before that if you are able to foresee how a change in the sport might impact results, you should make hay while the sun shines because at some point the market will catch up to you. It has to, and only a fool would think that it won't. 

Of course winning strategies should eventually go "tits up" as Joseph puts it, and there should be no need to "save face" when this happens, unless you are claiming your golden goose will live for ever, and yes, there are probably gullible fools out there who would believe that line. 

As Alfred Lord Tennyson put it so eloquently:

'Tis better to have loved and lost than never to have loved at all.

Assuming you didn't lose all your profits of course.

That some biases appear to be so strong that systems like the Small Road 'Dogs have had more winners than losers in effectively a coin-toss for 19 seasons and counting is the real puzzle:

All my strategies, and those of anyone, should have a limited shelf-life. The key is to identify current market inefficiencies, use them to your advantage until the market catches up and it is no longer profitable, and move on to the next idea. 

Remember that the ideas offered on this blog are all based on technical analysis and are all offered for free, although donation to the retirement fund are always gratefully received. 

The main idea for this blog is to show the process required to identify market inefficiencies rather than offer selections themselves. I hope it also shows that making a profit from betting is also possible with the right approach.

Mean regression might be meaningful (pun intended) if you are measuring the performance of a tipster who is using fundamental analysis to identify selections, but for a technical system where the market is always changing, it is not. 

The idea that markets evolve shouldn't be news to anyone who is actively betting. I don't believe Joseph actually bets on a regular basis, and thus may not be aware of these changes, but as others on various forums have pointed out over the years, successful strategies can stop working literally overnight. 

You're basically buying a property on top of an eroding cliff. At some point, your house is going to fall into the sea, but you should be able to enjoy the view for a while before that happens.

Build up your bank while you have the edge, move a stop-loss up as your profits increase, and stop betting when (not if) your stop-loss gets hit. The idea that one should wait until the system has been 'proven' over 10,000 events, possibly going back years when the markets were quite different, is frankly nonsense. We're not testing a coin-toss or a roulette system - we're playing in constantly changing markets. 

The idea that betting markets evolve shouldn't be a surprise - the financial markets do too, and a punter, like an investor, needs to stay flexible:

The important thing to remember is that there is not a set rule you can apply. You must factor in what is going on in the world. For example, if the economy is in trouble, corporate earnings can be worse than expected. This lowers investor expectations, and stock prices will go down. Even if the market seems fairly valued at a P/E ratio of 14, bad times could cause the market returns to continue on a downward spiral with the P/E ratio going much lower.

On the other hand, during booming economies, corporate earnings can continue to rise, and stock prices can continue to rise for many years in a row. A P/E ratio of 16, or even 20, does not automatically mean the market is overpriced. In the early ’90s, many thought the market was overvalued based on P/E ratios, and thus they missed years of great returns from 1994 to 1999.

The point is that the betting landscape is constantly in a state of flux. New players with new ideas and sometimes sophisticated analytical tools, come in to the markets, sportsbooks with revolutionary business models appear or disappear: 

When Pinnacle began trading in 1998, most gaming companies used bonuses to lure potential customers. Rather than offer sign up or reload bonuses, Pinnacle became the first sportsbook to introduce a reduced margin pricing model or reduced juice, thus deriving profit from lower margins but a far higher turnover. Pinnacle began offering -105/-104 ($1.95-$1.96) prices on head-to-head match odds and spreads, significantly undercutting the standard -110 ($1.91) pricing model that was used by its competitors.

These changes are why the challenge of betting profitably is so much fun. 

What happens when NBA teams play faster and increase the number of possessions per game? There are more points scored. Do the 'traditional' sportsbooks sit and wait for mean regression? No, of course not. There is no 'mean'. There are 'means' over certain periods of time, but they are generally pretty meaningless (sorry, did it again). 

Finally, Mark had this to say on the topic of bookie restrictions:

Hopefully by mentioning him, his interest will continue for at least another day or two, but my point on this topic was really that anyone with the ability to become a long-term winner at betting is unlikely to be someone who would be surprised at having their business declined. Or as I put it last year:

Are you suggesting that someone with the skill to win at betting long-term is someone who would be unaware that they might not be able to extract money from a business indefinitely? This seems highly unlikely to me.

Anyone starting out today on Betfair is certainly well aware that in the unlikely event they are successful to the extent of the lifetime limit, there will be a Premium Charge applied on future profits. The complaint from the relatively few customers impacted at the time, (in reality, far more people were complaining than were, or would ever be, affected by the charges) was that the lifetime limit was being retroactively applied, and if you were already there or almost there, it was unavoidable, whereas if you were just starting out, it was fairly easily avoidable.

But life goes on, for me it's only a hobby, and we adapt.

Hopefully a few of you were with me on the Unders last night in the NFL Wild Card games. With two winners already, the worst case scenario for the weekend is a small loss after commission, but while my 'official' results will record the wins at 1.952, the actual bets were made at 2.08 (Tennessee Titans @ New England Patriots) and 2.02 (Buffalo Bills @ Houston Texans) so it will be a profitable weekend no matter what. Fly Eagles Fly. 

 

EPL Draw - Under Consideration

A Happy New Year to everyone reading this, and 2020 is the 13th year in which this blog will have active. This will be post number 1,660 with the current posting rate for the past two years somewhere around two a week, which is probably sustainable for a little while longer. 

While the pedant in me knows that the 202nd decade of the Common Era doesn't end for another year, I'm reasonably comfortable with going along with the masses and thinking of the 'twenties' as a new decade, and the last one was certainly interesting from a betting and investment perspective.

Betting is too individual to draw any sweeping generalised conclusions about, but personally the big change, to use investing terms, has been from active (in-play) betting to passive (bet-and-forget) betting. 

The first investment anyone makes is time. You must do this prudently before you can be successful investing money.

Some of the free time gained from not betting in-play at all hours of the night has been spent researching ideas for the bet-and-forget approach, but the importance of sleep should not be underestimated.

At my advanced age, betting returns are a small percentage of income, with net worth changes hugely dependent on what the financial markets are doing, and long time readers will know my thoughts on low cost index funds and investing in the US:

In more traditional financial markets, once again the main US benchmark index outperformed the UK's FTSE100. Only 4 times in the last 24 years has the FTSE prevailed, and the disaster that is Brexit means the US and Overseas markets are where most of my investments will again be in 2018.

Here are the updated numbers for the last 'decade', and with 9 out of 10 'wins' for the S&P 500 and an overall 189.7% gain over the period, I have no plans to change this strategy in the near future.

Anyway, most of you are here for betting and I've not written about the EPL Draw since the summer, but as the 2019-20 season is now in its second half, it seems like a post on the topic is overdue. 

One of the more popular posts of 2019, at least in terms of views, was this one detailing my history with the Draw, and the importance of selecting matches where the difference in win probabilities is relatively small. While this isn't the most complicated of calculations, it does require a little effort, but here is an idea that requires literally no effort at all.

Long time readers, and followers of the XX Draws from several years ago, will know that there is a correlation between the Unders (under 2.5 goals) and the Draw: 

These selections are also profitable when the Under 2.5 goal selection is backed. I first noticed this early in the 2011-12 season, and I started recording these prices at that time.

When you are looking for draws, you obviously want matches where the probability of goals is low, and as I have written on my blog, in a way, it is more satisfying to select a match that ends 1-0 than it is to fluke a 5-5 draw as I did on the last game of the 2012-13 English Premier League season.

Prior to this season, I didn't have access to an accurate closing price for the Under 2.5 goals markets. Joseph Buchdahl's Football Data web site included Maximum and Average prices from several sportsbooks, but the numbers were all over the place.

However, starting this season, Joseph has added the Under closing price from Pinnacle, and the simple strategy of backing the Draw in matches where the implied probability of Unders is above 0.5 has so far proven to be profitable.

As a benchmark, backing the Draw in every EPL game this season (never a good idea, so don't try this at home) would have cost you 10.34 units, an ROI of -4.95%.

Forget matches where the Draw is priced at 4.0 and the ROI becomes positive at 3.91% and if you only back the Draw in matches where no side is odds-on, the ROI is up to 7.11%.

Looking at matches where the Under 2.5 goals is sub 2.0 and the ROI is a very nice 24.4% (15.89 units from 65 bets). 

And the return is even higher as the probability of goals declines:

If you combine the strategies mentioned above with matches where the difference in win probabilities is less than 20%, the ROI is currently at 62% but half a season isn't the largest of samples.

Dionysios tweeted the following recently:

I'm not so sure this necessarily makes sense. My character restricted reply was that: 

The point is that the betting markets of today, like the underlying sport, are not the same as those in the past. The sports themselves change as do the markets, so comparing the results of a concept or an idea which may be profitable today with results from the past is somewhat limited in value. 

While there are obvious exceptions where markets continue to be inefficient because biases can be extremely stubborn, it seems logical that inefficiencies will, in general, be recognised, and self-correct as money comes in to take advantage, often resulting in an over-correction!

Dionysios' idea seems to revolve around in-play football, which seems optimistic to say the least given the level of competition that is analyzing and investing profitably in this sport's markets. 

As I've written before, tracking the number of minutes elapsed in a game from your bedroom isn't going to cut it. 

Speaking of wild optimism in in-play football, is my old friend Mel (Scientia Trading) still raking in the profits? Things seem to have gone very quiet, although it is quite possible that I've been blocked and am missing out on the continued success of his claimed 60% strike rate at 2.8...   

The NFL play-offs get underway today with the Wild Card games where historically the value is on Unders. Only twice in the last fifteen seasons has Overs 'won' more than two of the four games, the last time being the 2011 season. Of the other thirteen, three were split for an overall 40-27-1 record.

The totals market is most inefficient for matches played on grass, but only one of the weekend's games (Philadelphia Eagles v Seattle Seahawks) is being played on this surface and it's the one game that sees the road team as favourite - despite having lost three of their last four games. I suspect the market is giving too much weight to the Seahawks 17-9 win in Philadelphia at the end of November although a road record of 7-1 is impressive.  

Road 'Dogs are generally under-rated at this stage also, with a 28-22-2 record ATS, and in the last two season are 7-0-1.  

Finally, the NHL system which struggled early on this season has bounced back with a seven game win streak and currently has an ROI much more in line with expectations at 22.4%.