Thread by @FlorisgoesF

In #football #Analytics we often refer to the analysis of attacks as sequence analysis, implying an attack can be modeled as a cascading sequence of events. A thread on why the term “sequence analysis” can be misleading.

#DataScience #Research

Despite the popular analogy (often used to describe strategic moves), #football is actually nothing like a game of chess. In chess, one piece can be moved at a time, after which the opponent reacts. In #football, 22 pieces can be moved simultaneously.

The movements of the 22 pieces are strongly bound together, and #Science has shown that attacking play is not the result of individual, sequential, actions, but rather the product of inter-player & inter-team interaction.

Chess players think in terms of action-reaction, and the best ones can “think 3 steps ahead”, if this then that and that and that. Research has shown #football isn’t determined by action-reaction, but rather by coupled interaction.

Thus “think 3 steps ahead” means something entirely different for #football players. It means deriving patterns from interactions, and seeing opportunities to break the coupling with an opposing team.

This has large consequences for the way we analyze the game. If a reaction cannot be attributed to a single action, how would that impact #Analytics?

Take the example of a pass, to whom should we attribute the decision to pass, and the chosen destination? Should this be the passing player, the receiver? In reality the pass decision is largely determined by the interaction of 22 moving pieces.

Off the ball, teammates try to get open, opponents try to block passing lanes, largely determining the resulting action. Ofc individual abilities & quality play their part, but any action can be seen as the product of at least multiple players on different teams.

In other words, 1+1+1 != 3 in #football #Analytics, just like pass + dribble + assist != goal. An attack is not the product of the sum of individual actions, but rather the product of interactions. But does this mean for you shouldn’t be doing sequence analysis?

The opposite, sequence analysis can be very valuable, when used to identify moments of interest.

Certain actions are likely to signal key phases of an attack, and can therefore serve as a starting point for analysis. One should be very careful however when attributing causality

Take an accelerating line-breaking pass, or a key-pass leading up to a shot. These actions are typically the product of a key-phase of interactions, and analyzing the preceding 5-10 secs can reveal valuable insights.

In #Analytics these moment are often framed as the action causing a result, while from the perspective of interactions, these actions are a result themselves.

In other words, if you want to understand the attacking determinants of succes of a team, finding the player that gives most key passes will not hold much meaning in and by itself.

If however you’d go back in time and study the interactions leading up to the action, you can start to identify patterns that determine the succes of attacking play.

Using #DataScience techniques and position tracking data, you can come to very interesting insights this way, unraveling the underlying tactical patterns.