Liverpool’s painful inability to take chances this season has now been well-documented. Last season, the Reds scored 59 goals from 434 shots, a conversion rate of 13.6%. This season 21 goals have come from 256 attempts at a paltry conversion rate of 8.2%.
I thought I’d illustrate this alarming decline by testing the probability of scoring 21 goals from 256 attempts given last season’s conversion.
If Liverpool’s ‘true’ conversion rate is 13.6%, there is a 0.5% chance of scoring 21 goals or less from 256 shots. This is a substantially small enough p-value to suggest the conversion rate has significantly fallen this season. No surprises there, particularly as we are quite a way into the season. (The chart above shows cumulative probability; that is the probability of scoring the amount of goals stated or less given an underlying conversion rate of 13.6%).
In other words, Liverpool’s conversion rate fall can’t simply be attributed to random variation, or chance. There is something fundamentally wrong with the Reds in front of goal this season – most would suggest it is a confidence issue.
Liverpool would’ve expected to have scored in the region of 34 goals this season given last season’s conversion rate.
If Liverpool have 15 shots per game over the next three games, they’ll need to score 10 goals over the three matches for a repeat test to suggest no significant fall in conversion rate from last season. As things are, that would be a serious goal glut.
