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Showing posts with the label Plus-Minus

Expected goals plus-minus

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As the season ticks on, we're starting to get a bit of data to work with, albeit sometimes in small samples. This season I am not working with a relatively complex player model but am really interested in trying to "play the fixtures" as much as I can. A couple of sources of frustration, therefore, have been as below: 1. Sites which provide the difficulty of fixtures often seem a bit simplistic. For example, the Premier League site shows Wolves as an average "3-rated" opponent, both at home and away yet the reality is more complicated. While at home they have been very solid defensively, with an Expected Goals Conceded (xGC) of just 4.71 in five games, which ranks third best, yet on their travels they have surrendered 7.94 xGC, which is the third worst . Even more confusing is that most sites ( though not all ) don't distinguish between attacking and defensive fixtures, so facing Leeds at home is presented as an easy "2-rated" fixture when in reali...

Team Plus-Minus Page

If you direct your attention to the navigation bar you will note that there is now a new link to the team plus-minus page. I've added a brief summary below but it's a pretty simple principle. One word of caution: the data is based solely on 2015-16 data so the sample sizes are ludicrously small. That said, these numbers (particularly with penalty box touches and total shots) do stabilise relatively quickly so it's worth at least having a glance at these numbers in the coming weeks if you are worried that your initial assessment of a team is a bit off (are Chelsea really struggling? Are Leicester for real?). Workings Plus-minus (+/-) is a very simple metric which simply tries to adjust stats to put them in a context of a team's opponents to date. For example, we might note that two teams have each registered five shots on goal per game and conclude they are of equal ability but if one team did it against Man City and Everton while the other did it against Norwich and...