Sunday, 22 September 2013

Subjective Objectivity

The inclusion of Sassuolo v Internazionale in this weekend's XX Draw selections no doubt raised a few eyebrows, including my own, but an objective spreadsheet doesn't read facial expressions too well, only numbers. With the season only three games old, the numbers for promoted teams, including Sassuolo, are largely guesswork, and as mentioned by Scott in an email today:

Selections involving newly promoted teams seem intuitively flawed, although it would be interesting to see if the numbers support this.
While we won't know until a few more games have been played how bad Sassuolo are, with four losses (including today's 0-7) and one goal scored, 15 conceded, it's fair to say that they are not looking too good. They did win Serie B last season and only one Serie B champion in the last 10 years has been immediately relegated (which was Pescara last season - more on those little devils later). I see a new trend starting. With Sassuolo's home ground having a capacity of 4,000, they play at Reggiana's stadium this year so perhaps all games should be treated as away fixtures?

I had a look at last season's promoted teams and how they fared when selected, and interestingly the worst league was Serie A. Pesky Pescara were selected 13 times, and not once did they oblige with a draw. Sampdoria were also selected 13 times, drawing only twice, but Torino helped out with four draws from nine selections. Promoted teams in Serie A thus had a strike rate of 6 from 35 (17.1%) and implied odds of 5.83. Clearly we would have been better off in this league by excluding promoted teams.

At the other end of the spectrum is the English Premier league, where the promoted teams were a combined 12 from 31 - a much healthier 38.7% and implied odds of 2.58. Interesting, again one promoted team (West Ham United) failed to draw any of the eight times they were selected, although Southampton more than made up for it with 8 draws from 13.

Across all five leagues, promoted teams were selected 154 times, and 41 ended in draws (26.6%, implied odds 3.75). Based on this evidence, promoted teams probably should be excluded, but the evidence is from just one season, and I'll continue to include them this season. Perhaps with a disclaimer something like "Warning: The inclusion of newly promoted teams can damage your wealth".

Why should these fourteen or fifteen promoted teams by singled out for special treatment? The reason is that while established teams have a solid rating after at least a year and 34/38 games of adjustment, the initial point allocation is necessarily partially subjective. I wrote an article on this subject a little over a year ago for Betting Expert. This season, I had to break my rules for Monaco and make a manual adjustment, as they were clearly not a typical promoted team. At the time of writing, this decision is somewhat vindicated by the fact that Monaco sit atop the league. Given time, Monaco's ratings would adjust, but to knowingly go several matches with a clearly false rating would have been ridiculous. The problem is where to draw the line. Do I adjust Tottenham Hotspur's rating after Gareth Bale is sold, or temporarily adjust Liverpool's rating while Luis Suarez sits out his latest ban? Clearly these are factors to be taken into account before you place serious money on any game, with the spreadsheet numbers just a starting point, but for the weekend warrior, there is only so much we can do.

Several tipsters seem to be struggling this season. Some say that it is still too early, and caution needs to be paid, and there's nothing wrong with that, but the problem is that if you eliminate too much of the early season, and then start wrapping things up in February because it's near the end of the season, you end up with a couple of weeks in late December or early January when the stars are aligned and it is an auspicious time to bet. I exaggerate of course, but one downside of subjectivity is that there are too many reasons not to make a selection.  

1 comment:

EMP said...

Couldn't agree more Cassini. If you wait till all is clear, there is no longer a price. I think the best opportunities are when other intelligent players feel that they don't want to be involved.

Two points to note:

a) If you were rating the lower league as well, there is no problem with promoted/relegated teams as you can have a seamless transition (unless of course 500M worth of incoming transfers off-season)

b) On transfers and things like that, I think it's just not possible to know precisely what impact new signings/departures/suspensions have, given that football is so team-oriented, that I don't know any particular way to predict whether loss of cohesion offsets improved quality, what the actual quality of transferred players is; etc. I am happy to defer to stats under most circumstances.

And another note, updated table? I have a sneaking suspicion I might have catapulted close to the lead.