So I asked over in the McHale Evaluation Post about the correlation between team's roster turnover versus their win percentage, but since no one knew, I eventually broke down and looked it up myself.
However, I'm sure there's flaws as I only had energy for this season and I counted by hand (using Basketball Reference) so I might be off. Also, since it's Basketball Reference and I only did a simple count, it doesn't take into account a team's pct before and after in-season trades. But because most in-game trades happen pre-break and there's a decent amount of games under a team's belt, that it'll be a quick and dirty simple reference.
These are the numbers I got (Win Pct from ESPN):
Which graphs out to this:
Upper Right ares team that's kept most of its players and are good, Upper Left are teams with lots of new players that are still good. Lower half are teams below .500.
And it's particularly interesting to compare it to this chart on Age versus differential (From SBNation NBA page: How the best and worst NBA teams stack up in terms of age).
Interestingly, the teams that are in the lower right quadrant of Age v. Quality are also in the lower right in Roster Turnover v. Win Pct.
Actually, let's try a Roster Turnover v. Quality too...
And you get roughly more separation with Houston, Clippers, and OKC. You can argue that OKC has gotten their age issue with low roster turnover, and that the Clippers around their roster turnover by adding vets.
But there's basically no excuse for Houston, and it seems that by any measure we're looking at something really special here.
(Someone not me should really look at Turnover V. Differential for the past 10 years. HINT.)
- Clippers and Knicks are both older teams with high roster turnover, but that didn't seem to help Boston and Dallas.