Long time readers will recall a discussion last summer about a stat I called xWSR, weighted expected success rate (I agree, it’s a mouthful, and I need some help in the PR department). My motivation for the stat was to evaluate teams based on the sum of their expected points change across the season. Simple enough, right?
I stole a lot of inspiration from baseball’s xwOBA stat, wherein a statistician has access to data regarding the quality of contact: exit velocity, launch angle, and direction of the hit. Then, putting those together, statisticians can attach an expected run value to each batted ball - a double is worth, on average, something like 1.