During after-match interviews, statements like “we dominated the opponents” or “we suffered their playing style too much” are common ways to express a coach’s perception of game dominance in soccer. However, they do not necessarily reflect the actual match dominance.
A new possible objective interpretation of game dominance relies on the concept of invasion index, a metric which quantifies a team’s ability to play close to opponent’s goal.
A team’s invasion index during a game can be computed with a simple algorithm:
– Split the game into possession phases, i.e., sequence of consecutive events on the ball generated by the team;
– For each possession take the event with the highest weight.
An event’s weight is computed as its “dangerousness”, i.e., the probability to score from the position where the event occurs.
-Compute the sum of all the weights obtained during the game.