http://www.ultimouomo.com/a-che-punto-sono-le-statistiche-nel-calcio/
That article was in Italian, and had plenty more contributors, so check it out, but here are my thoughts pre-translation, for anyone interested.
How can analytics evolve beyond xG?
Expected goals provided a strange line in the sand for football analytics primarily because the data required to build a reputable expected goals model fell outside the published statistics from public sites and the technical aptitude to build such a model was specific and not trivial.
So for a long time, people built xG models, or looked on from outside wondering about xG models. This had the effect of slightly focusing the evolution of football analytics around xG related topics—people built ever more complex models, and eventually graduated towards models that valued the movement of the ball wherever it was on the pitch, but the basic concept was still an expected goal value.
More recently studies of passing have become more prevalent a with a desire to identify players and teams that are most efficient or successful at moving the ball. Still though it is difficult to separate descriptions of style from actual beneficial results that tally with winning football matches--a long term core issue with any metric development.
There is a lot of hope for tracking data, that it might add in extra factors that aid precision but nothing is public there yet and it's possible that benefits from that will only be marginal, a charge that could also be laid at the addition of running and sprinting data.
Defensive analysis remains hard to work with at a player level and it must be hoped that advances in quality of data can shed light here.
Stats in the media
The level of stats use in the media
has seen a sharp rise in recent years, and with fantasy football,
Football Manager and data sites such as Squawka and Whoscored, the
acceptance of numerical descriptions of players is firmly entrenched
in younger fans' minds. More often we see talk of shot or shot
creation numbers for teams and players which add a necessary second
layer for analysis beyond goals and assists (xG may still be too
esoteric for total mainstream usage) and this is positive.
Less positive is the use of other
statistics that do not represent what they are being used for.
Defensive stats like tackles and interceptions are often presented in
a more = better fashion, when they are little more than descriptive,
they do not necessarily reflect quality of play. Goalkeepers cannot
be graded accurately by volume of saves and simple lists based on one
or two stats do not do a good job of grading players outside of
attacking metrics.
So we have more presentation of stats,
more description of stats, but a long way to go to before actual
nuanced and thoughtful analysis of stats is anything like normal. And
there is certainly a knowledge gap here. It takes time and
understanding to read genuine meaning into football statistics yet
there is a requirement for media companies to incorporate information
to their presentations, and maybe only in certain cases is this
backed up by genuine understanding. This same problem presents
itself inside clubs, where performance analysts are bringing
statistics into their work without sufficient grounding in what
matters and what does not. Until both the media and football
understand that they require knowledgeable people to direct their
usage of stats, offerings will fall short of their potential and we
are in danger of finding stat use marginalised (in clubs) or used as
trivia but nothing more (in media).
