Blinded by stats?

Fantasy Football Scout member Cheeseoid asked today who he should play from two goalkeepers whose teams face each other tomorrow: Kasper Schmeichel or Jack Butland? He was answered by a string of people saying Butland… until I came along and said Schmeichel.

Butland v Schmeichel

None of those advocating Butland gave a reason for their decision, but I assume most named the Stoke City stopper because of his performance last week against Arsenal. It might be they watched Butland’s display and were recommending him because he played well. Or maybe they remembered he recorded 10 saves and earned three save points that helped minimize the impact of conceding twice. They were his fifth, sixth and seventh save points of the campaign so the suggestion was not without merit. Schmeichel has just two save points this season.

However, it is worth remembering that a goalie gains one save point for every three saves made. Rarely will a keeper record the four points needed to match the points accrued for securing a clean sheet. If the keeper is facing that many shots on target, the chances are he will concede, reducing his points return by one for every two goals given up.

If a goalie can pull off that many saves and keep a clean sheet he is probably looking good for a nice haul of bonus points too, but a high-save clean sheet will be a lower percentage play than looking for a regular clean sheet. It’s also worth remembering that Leicester are not Arsenal. Despite scoring more than twice as many goals as Arsenal, the Foxes have done so with 40 per cent fewer attempts on goal. That doesn’t bode well for clean sheet points or save points for Butland.

Some may argue that Schmeichel, like Butland, hasn’t kept a cleansheet this season so, if both defences look leaky, go with the keeper who will bring you more saves. There is logic in that: Stoke have conceded 35 per cent more big chances than the next worst Premier League team this year and the Potters sit third for shots in the box conceded. Given those stats, the fact they are only joint sixth worst for goals conceded could be a good reflection on Butland’s ability.

However, there’s also the possibility of getting blinded by save points to the detriment of other useful data. I said Schmeichel because I took a quick look at the goals scored and goals conceded numbers for both sides. Both sides have conceded seven goals so there’s nothing between them there. But Leicester have scored 11 goals while Stoke have scored just three this season; Stoke have scored in 60 per cent of games played, while Leicester have scored an average of more than two goals per game. The underlying data suggests Leicester is over performing and Stoke under performing, but those numbers still say the Potters don’t carry a great attacking threat.

Leicester Stoke goals scored

Butland may produce more heroics to secure a huge haul of points, but it seems to me that there is a better chance that Leicester records a simple clean sheet.

We’ll find out the answer for sure in a few hours, but the exercise was a useful reminder to not become overly fixated on one or two stats.

I tend to use a handful of stats on this blog to analyse players. I do so because it allows comparison but avoids posts getting bogged down in too much detail. But please don’t read my analysis in isolation – add it to what else you know and welcome it or reject it as you see fit. And if you think I’ve missed an important detail, please feel free to add it in a comment. Thanks!

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2 thoughts on “Blinded by stats?

    • Thanks Doosra, so your ticker is liking Stoke for this one? I’m guessing your prediction is built upon a multitude of data, more than that captured in my musings above.

      Like

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