Little basketball analytics rant. I’ve been seeing more and more people on my timeline use points-per-possession (“PPP”) when talking about actions (and even shooting?). Maybe my timeline has just gotten more college basketball-heavy, but PPP has quietly become a catch-all stat, and it’s getting stretched way past what it measures. PPP is a team efficiency number. It’s great for game- or season-long efficiency, and it’s usually what you’re seeing reported as offensive/defensive rating. When we’re measuring action-level events (picks, drives, isolations, etc.), we want points-per-chance (“PPC”). A chance splits possessions into distinct scoring opportunities, broken up by offensive rebounds and dead balls. Say you run a pindown and the pass gets deflected out of bounds. From the side-out, you run something else and score two. The pindown produced zero points, but PPP credits it with two because you scored on the same possession. PPC gives it zero. If you want to be more precise, you can attribute putback points to the chance that created the miss. Then there’s the concept of direct chances (and true points/shot for shooting!), but this post is already long enough.