By Matthias Kullowatz (@mattyanselmo)
Perhaps I played my best card too early, publishing year-to-year expected goals correlations first. I won't waste a lot of words explaining what's going on here, but basically I'm just looking to see what shooting metrics correlate from the end of last year to the beginning of this year. This time, let's go back and look at raw shot totals. Without further ado, to the pretty plots!
Shot-to-shot correlations hold up pretty well against expected goals when it comes to repeatability. However, that doesn't necessarily mean they should be used in predictive models in place of expected goals. Expected goals not only predict themselves well ("stability"), but also predict outcomes well, like goals scored and games won.
For the most part, we see stronger correlations between shots on target than between total shots. This is not the first time I've found that some form of goal mouth placement at the team level is repeatable. The expeted goals model we use for goalkeeper ratings is based partially on placement, and this version of expected goals will almost surely creep into my prediction models this season.