Updated Raw Expt Pts post 2018 Championship

The last published Expected Points (Expt Pts) numbers are contained here. I would strongly recommend that everyone, whether you are currently using Expt Pts or not, (re)read this piece as it outlines the methodology used and more importantly the inherent weaknesses in the numbers.

Changes since last publication

Those numbers were produced in early 2018 but had not baked in the 2017 returns … so in effect were created off Championship data up to and including the 2016 season. Some 70 Championship games have been added to the database since then so it is time to update the numbers.

A quick review of some changes

a) Firstly all attempts, inside Section 8, have been coded as being with the hand or the foot. This does not get anywhere near representing the quality of goal chances but, as can be seen in the differences for both, is a worthwhile change.

b) Secondly the raw averages have been dispensed with and instead a weighting is now in effect; 30% of total outcomes are taken from the two most recent years with 20% each for the two years preceding this. What is happening in more recent years is more prevalent in the Expt Pts output but we spread the return across the four most recent years to ensure any one year change/blip does not completely overwhelm the model.

c) This is the case except for rarer shots (sideline attempts, 45s, penalties etc.). For these we take all the shots in the database rather than applying the weighting. This gives us more certainty on the numbers.

Outcomes
Yes. Yes. Yes. We understand – just give us the bloody numbers …

Caveats
As ever Expt Pts is not the be all and end all. It is another tool to use when honing in on shooting efficacy. One tool (albeit a better one than Conversion Rates). No more, no less.

Consider these numbers as “Raw Expt Pts”. No overlay. No subjectivity. They are the product of the 80:20 rule. A newer model, which overlays strength of competition and game state, is currently in production. The thought behind this updated version is expanded upon here.

That will undoubtedly produce better numbers but it is not necessarily something that can be transferred easily to club football. As such the numbers here are better in that respect.

Happy statting.

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