For those of you who don't know, XPPS stands for Expected Points Per Shot. We all know certain types of shots tend to yield a greater amount of points then others, (close-range>3-point>everything>mid-range) so the folks over at Hickory High analyzed every shot/shot location over the last 11 years or so. The metric is XPPS, and if you have a high XPPS, you are taking great shots. The opposite is also true.

For this post, you should also be familiar with XXPS difference. This is the difference between each players/teams expected XPPS (based on shot locations), and their actual PPS (based on what actually happened).

Not sure if this was done anywhere else (I checked and found nothing), and I was curious. So, I regressed every team's XPPS and XPPS Difference against their respective winning percentage, from 2004-2013, and the results were interesting.

There is a 1.17% correlation between taking good shots (high XPPS), and winning percentage (winning games). Wow. I would not have called that.

There is a 21.2% correlation between forcing your opponent into bad shots, and winning.

There is a 32% correlation between having a high XPPS difference (shot making), and a high winning percentage.

There is a 34% correlation between forcing a low XPPS difference (shot missing), and winning games.

Okay, a few things jump out. Shooting "good" shots doesn't seem to have a significant impact on winning, which goes against everything we know about everything. However, "making" shots, whether good or bad, has a much larger impact on winning. Lets go into XPPS Difference a bit more.

What would cause a team to have a high XPPS Difference? Two things.

1.) They have great shot-makers.

2.) They are getting open shots

Again, the opposite is also true.

So when we consider XPPS Difference is essentially measuring how open your shots are, and how good at shooting your team is, then it makes sense that XPPS Difference is more important then XPPS.

Given that, I averaged each teams XPPS Difference with the XPPS Difference they give up, and regressed them against winning percentage, from 2004-2013. The result was a 64.4% correlation. Therefore, we could say that 64.4% of wins in the last 8 years came down to winning the XPPS Difference battle.

That's all for now. If teams want to win, they need to win the XPPS Difference battle. I'll probably due a follow up post where I only apply this to playoff teams or champions, to see how XPPS can influence championships.