Expected threat
xT°An estimate from a model we built. Useful, but not a fact — every modeled stat's page says where it's weak.
Definition
The pitch is divided into zones, each carrying a value: the probability that possession starting there ends in a goal. Moving the ball from a low-value zone to a high-value one generates expected threat equal to the difference. Only successful moves score. A pass that is intercepted, or a clearance that concedes possession, generates nothing.
How it is computed
Zone values are solved iteratively over the transition and shot probabilities observed in the event record. Credit is awarded only to actions that keep the ball.
How much is enough
Per-90 figures settle around 600–900 minutes.
Where it is weak
Blind to whether a pass was difficult. A simple square ball into a high-value zone scores the same as a line-breaking one.
What it refuses to measure
xT does not value shooting. It values ball progression, so a striker who only finishes will show near-zero xT and may still be excellent.
What would prove this wrong
If team expected threat summed over a season fails to correlate positively with points, the credit assignment is not measuring threat creation. An earlier version of this model failed exactly that test, because failed passes and clearances scored.