Welcome to the first weekly edition of SuperGrover’s team
rankings! If you are new to the site,
you can find some background on the topic here. Before we unveil the rankings, let me walk
through the process in which they are derived.
The first step in formulating team rankings is to analyze
attacking and defensive performances so far this season. Rather than use goals themselves which are
prone to luck and sample size problems, I use a more complex model which combines
shots on target and Big Chances to predict goals scored and conceded. Thus, I use a team’s shots on target and Big
Chances, both for and against, to determine how many goals that team should have scored and conceded. This value is the basis of each team’s attack
and defensive quality.
While valuable, those rates are not enough. You need to adjust that rate by quality of
opposition, factoring in opponent’s quality of play and home advantage. While the impact of schedule is eventually
nil, early in the season opposition strength can be badly skewed. Hence the need to accommodate.
Determining opponent strength is done by calculating the
ratio of each team’s goals scored/conceded in comparison to the average goals
scored/conceded by each club on its schedule after factoring for home pitch
advantage. A clarifying example:
In this case, Team A has an attack that is 20% better than
“average” and a defense that is 5% below “average” (lower defensive numbers are
better). Note that “average” is quoted
as this does not represent the average of all team attack/defense ratings but
rather a team who performs exactly as it’s strength of schedule would predict
(i.e., 100% ratings for attack and defense).
That’s pretty much all there is to it!
Once calculated, I can use these ratings to predict scores
between any two teams, home or away.
That calculation is simple; I take one team’s attacking percentage and
multiply it by the other team’s defensive percentage and vice versa. This gives me two predictive factors for each
team. I then take that factor against
average goals scored in the league thus far, deriving expected goals produced
for each team. All of these factors are,
of course, adjusted for home pitch advantage.
That is the process for defining my team ratings in a nut
shell. Below you will find this week’s
ratings and predicted scores. Starting
next week, I will provide commentary on each week’s games, identifying fixtures
in which the model simply broke down.
The Total rating below represents the combined
percentage advantage over a team with attack and defensive ratings equal to
100. It is simply a sum of attack rating
over 100 and defensive rating below 100 with no additional adjustment.
As always, questions, comments and criticisms are strongly
encouraged.
Projected Scores:
NB: The score prediction model SuperGrover uses differs from the one used for the main articles, projections and captain picks on this site.
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