Event data vs Tracking data
The matches with only event data available use only tagged on-ball actions such as passes and shots. The matches with event and tracking data available combine these on-ball actions with positional data of all players and the ball. This allows detection of off-ball movements and pressure, offering deeper tactical context and more refined sequence definitions.
Definition of Ball Starts (BS)
A Ball Start marks the beginning of a new sequence. How it’s identified depends on the available data.
Event Data Only (BS)
With only event data, a sequence always starts from a set piece (e.g., throw-in, free kick, goal kick). The pitch is divided into 4 zones, and each Ball Start is classified as follows:
BS0: Goal kicks or throw-ins taken at the height of the team’s own penalty box.
BS1: All other set pieces in the same zone as BS0, except BS0 set pieces.
BS2–BS4: Set pieces taken in progressively higher zones up the field.
No information about player positioning is used, only the type and location of the set piece.
Event + Tracking Data (BS)
When event and tracking data is available, we still apply the same requirements as event data BS0–BS4, but now non-set-piece starts can be included as well.
For example:
Keep-ball starts: A sequence of events that involves a team maintaining possession without making any significant progress up the field.
Tracking data adds tactical context: it reveals pressure, space, and off-ball dynamics helping detect more nuanced sequence starts.
How BS1-BS4 is divided (BS0 = zone 1 as well):
Sequence Result
Both event-data only and event + tracking-data categorize results as Negative, Neutral, or Positive, ensuring consistency across outputs. In event-data only, results rely solely on the last tagged action. Tracking data captures player movement and defensive pressure, not just ball events. This enables a more accurate determination of when an attacking sequence truly ends, especially in cases where the decisive moment occurs off the ball rather than through a clear event like an interception or tackle.
Sequence Outcome
The event-data only includes four outcome types:
Transition
Ball Dead
Shot
Penalty
It can’t recognize cases where the ball is held or no clear end occurs.
The tracking- and event-data contains three extra outcome types:
Keep Ball
Goalkeeper End
No End
These additions better capture possession phases, keeper control, and undefined endings.
Summary comparison table
Feature | Event only | Event- & Tracking data |
Definition BW 1-4 | Open-play transition only | Open-play transition only |
Definition BS | Set-piece start only | + keep-ball situations |
BS0 | Goal kick or throw-in at height penalty box | + pressure situations |
BS1–4 | Set-piece from Zones 1-4 | + undecided endings (such as keep-ball) from zones 1-4 |
Result categories | Negative, Neutral, Positive | Negative, Neutral, Positive |
Outcome types | Transition, Ball Dead, Shot, Penalty | + No End, Goalkeeper End, Keep Ball |
Insights | Interpretation: context from just tagged events as input | Interpretation: context from tags and (ball)positions as input |