One of the biggest critiques of analytics and statistics in
general is that they don’t take into account intangibles like confidence, “wanting
it more”, desire and heart. On the surface this seems like a fair argument, we
don’t have a statistic for leadership, heart and character per 90, but to
suggest analytics is ignorant of these ideas ignores how these factors actually
affect the game.
I’m not a sports psychologist so I’m not going to say which
of these intangible traits matter in a game like football and which don’t, but
let’s assume for the sake of argument that some of them do matter. I don’t
think this is a ridiculous assumption, personally I’m much better at a lot of
things when I’m confident or motivated.
Assuming these things do matter there’s a few ways they
could present themselves on a football pitch, let’s unpack these one-by-one.
First imagine two players, let’s call them Heart of a Lion
Joe and Lazy Bob. On a purely technical level Heart of a Lion Joe and Lazy Bob
are equivalent, they are both strikers and have the exact same skill set. What
is different about them comes down entirely to attitude. Heart of a Lion Joe
loves football, has lots of heart and always wants to win football matches
above everything else. Lazy Bob isn’t that bothered about winning and probably
won’t commit to a 50-50 ball with the same vigour that Heart of a Lion Joe
will.
Individual Effects
Now assume that intangibles affect the game through
individual effects. That is to say that because Heart of a Lion Joe has better
intangibles than Lazy Bob he will be a better player. Well if he is a better
player because of these intangibles than these effects will show up in the
data. Sure in a comparison of individual skills outside of a game context Heart
of a Lion Joe and Lazy Bob are identical, but if these intangibles really do
make you a better player then we will see that Heart of a Lion Joe putting up
better numbers than Lazy Bob.
Since they are strikers we will probably see Heart of a Lion
Joe score more and take more shots than Lazy Bob because he “wants it more” and
will be more aggressive in going for the ball or pushing himself that little
bit harder. So sure in the statistics we won’t see that Heart of a Lion Joe has
more ‘heart’ than Lazy Bob, but we will see that Heart of a Lion Joe is a
better player who puts up better numbers than Lazy Bob and if we are capturing
that does it really matter that we aren’t capturing the exact intangible that
makes him better? Probably not.
Team Effects
The second argument that anti-stats people will tell you
about intangibles is that you can’t measure them because they don’t just affect
one individual player they affect the whole team. When a team plays with Heart of a Lion Joe up
front it gives the whole team a boost and they all play better because they are
inspired by Heart of a Lion Joe’s incredible leadership. When Lazy Bob starts
up front though he just mopes around and that dampens everyone’s mood.
Well luckily we can measure this as well! Using Shapley
Values or GoalImpact we can compare how players affect their teammates. These
are completely agnostic measures which means they don’t try and pin down the mechanisms
through which players are making their team play better or worse they just
compare how the team plays with or without them in the team (weighting for
other factors like who they are playing with, strength of opponent etc.). So
even though there isn’t a way to directly measure how one player’s intangibles
affect another’s, if these mechanisms exist they will be picked up by Shapley
Values or GoalImpact. Good news for Heart of a Lion Joe, we can even figure out
if he makes his teammates better through his inspiring leadership.
One argument against this method, which is probably the only
one I don’t have a good answer for is that maybe a player’s magical leadership
qualities are so powerful that he doesn’t even need to be on the pitch to
transfer them to his teammate. His presence in the dressing room alone is
enough to make his team better. If that’s the case then maybe there is room to
hire players purely for their dressing room abilities, but we probably
shouldn’t pay them player’s wages. Teams should hire these people as
inspirational speakers or as people who just “hang out” with the team.
Jekyll and Hyde
After all this time maybe we find out that Heart of a Lion
Joe and Lazy Bob were actually the same person. When he’s playing well he has confidence
and takes on the persona of Heart of a Lion Joe and when he’s playing poorly he
becomes Lazy Bob. This is probably the narrative we hear most often in the
media, the confidence storyline. Analytics people respond to this narrative by
saying it’s just random variation.
If you take off your analytics-tinted-glasses for a second
you have to admit the mainstream media story of ‘confidence’ is a lot more
satisfying than ‘randomness’. Randomness is an ugly word in sport. We like to
think that everything happens for a reason so attributing these changes in
performance level to confidence just feels better than saying it’s random
variation.
The correct response here is who cares? Really, maybe the
media are right and all random variation in scoring or performance level comes
down to confidence, but it looks random from a data perspective. All that
matters in the end is output, so if a player can’t control when he is Heart of
a Lion Joe or Lazy Bob then why should teams?
If it looks like random variation that the player can’t
control and it acts like random variation the player can’t control then for all
intents and purposes we should treat it like random variation the player can’t
control. Sure, maybe it’s confidence but if confidence is completely exogenous
to what a footballer has control over why should teams care about it or
evaluate based on it?
The mainstream media is probably right that the footballing
world is full of mixture of Heart of a Lion Joes and Lazy Bobs, but they are
wrong to suggest that analytics ignore the differences between these two
players.
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