SoccerSTATS.com - updated on: 18 Jun 2020
The Relative Performance table aims at contrasting some basic team performance indicators such as Points and Points Per Game,
by factoring-in how presumably easy or difficult each team's played matches might have been.
The resulting Relative Performance Index is calculated for each team, based both on Points per Game and on an evaluation of
the team's played opponents Points Per Game.
You may also want to read more contextual information regarding that table on the following page:
Evaluating team performance
The table lists team ranked by points and shows, for each team:
- Games played
- Points Per Game
- Opponents Points Per Game
- Relative Performance Index
Below is a view of some of the columns of the Relative Performance table:
Points Per Game (PPG)
The value is calculated based on the number of points for each team, divided by the number of matches played by the team.
Opponents Points Per Game
The Opponents PPG value is calculated based on the combined value of Away Points Per Game of opponents played at home and
Home PPG of opponents played away. The details of each opponent PPG value can be displayed by hovering the mouse cursor over any
Opponents PPG value on the table.
Relative Performance Index
That value is calculated by multiplying the team's PPG value with the played opponents' PPG value.
Such Relative Performance Index (RPI) is aimed at giving a sense of a team's performance in terms of results, by taking
into account how "easy" or how "difficult" the points picked up by the team might have been. To estimate such a "difficulty level",
the RPI uses the Points Per Game of the opponents already played by the team.
In the example below, two teams are equal in points (18 points each) and, as they have played the same number of matches, their Points Per Games ratio is
logically identical (2.00 PPG for each team). However, since one of the teams has played opponents that have a higher combined PPG (1.48 vs 1.41), that
team has a higher RPI value.
Another example, if Team A has a PPG a little bit lower than Team B's PPG, but with Team A having already played against the toughest opponents while
Team B so far only played against lower-level teams, then Team A's Relative Performance Index might end up being higher than Team B's, despite Team A having
fewer points and a lower Points Per Game value.
However a higher RPI will not necessarily mean a superior strength. It only includes an estimation of the oppositions' strength in the equation,
instead of focusing only on total points or Points per Game.
You can view an example on the Relative Performance page for the Bundesliga.
The Relative Performance Index value calculation gives as much importance to the team PPG as it does to the Opponents PPG.
The idea is to apply some sort of "weight" to a team's PPG, in order to factor-in the level of opposition the team's points have been picked up against.
However in the early stages of the season, the PPG values can be much higher or much lower than what they become as the season progresses.
This may cause such a calculation, based on PPG averages, to use values that can be more extreme at the begining of the season.
The more matches have been played in the season, the more meaningful the PPG values will become.
In addition to the RPI, another statistics table making use of opponents PPG is the Run-in analysis table,
which is also discussed in Evaluating matches difficulty-level.