This isn't how xG works
This is more or less correct
Each shot is given an xG value based on how likely it is to be scored, which primarily takes into account exactly where the shot is taken from, the angle to goal, the position of the goalkeeper, and whether it was a header or not. A goal is scored roughly once every 9 shots, so the average xG value is around 11% / 0.11
The xG value you see on MOTD are the sum of all the individual xG values over the course of the match for each team.
If you look back at our chances, in particular the 2nd and 3rd goals, both would have a pretty low xG value. Foster will have been expected to save the 2nd goal considering how far out it was, and for Hemed's he managed to squeeze it in at the near post where again Foster would have been expected to save it.
On the other hand, West Brom's goal and their chance at the very end each both had quite high xG values, both were about 8 yards out and very central.
This article explains it better than me: http://www.optasports.com/news-area...oals-makes-its-way-into-mainstream-media.aspx
Wow - I had no idea about any of this ridiculous and frankly meaningless analysis by accountancy.
Talk about sucking any last vestige of romance out of the Beautiful Game for no useful purpose whatsoever.