Does John Hollinger trust PER? Should we?

John Hollinger created Player Efficiency Rating (details about its calculation here). As John himself puts it,

The PER sums up all a player’s positive accomplishments, subtracts the negative accomplishments, and returns a per-minute rating of a player’s performance.

 

After a successful writing career for ESPN.com, the Memphis Grizzlies hired Hollinger as their VP of Basketball Operations. In his first season as VP of Basketball Operations, Hollinger’s most significant move was trading Rudy Gay for Tayshaun Prince, Austin Daye, and Ed Davis.

From a Wins Produced perspective, that’s a heck of a deal. Rudy Gay is unremarkable; Prince is solid; Daye seems to be productive when he’s played on the perimeter; and, Ed Davis is among the most underrated young big men in the league.

But what about from the perspective of PER?

Prior to the trade, Rudy Gay’s PER was 14.1, just below Hollinger’s average of 15. Prince’s? 12.7. Daye’s was also 12.7 in a weird coincidence, and like WP, PER says Davis is the best player of the bunch at 18.2.

Interesting, right?

When we look at minute distribution since the trade, it’s stranger still. For all intents and purposes, Tayshaun Prince is playing Rudy Gay’s minutes. And even though Daye and Davis have had some good moments, they’re not playing enough to matter.

Practically speaking, this trade was Rudy Gay for Tayshaun Prince.

From the perspective of PER, we’d expect the Grizzlies to be a little bit worse, at least so long as we look at it from a Prince-for-Gay standpoint, which is what it is in practice. Not a lot worse, but a little. But the Grizzlies are not worse. In fact, they’ve been quite a bit better since the trade (obligatory small sample size qualifier . That good play hasn’t been because TAyshaun Prince is playing like an All Star. He hasn’t been. But, Tayshaun Prince is quite a bit more productive all things considered, and that is certainly helping.

The question that then begs to be asked is, “Does Hollinger trust his own metric?”

There are a couple obvious counterpoints to my implicit point in that question. I’d like to quickly respond to some of them.

First, for those who followed the trade as it happened, it was obvious there was a financial reason to do this deal (and the one that immediately preceded it). Fair enough. But Hollinger flat out says that he believed Tayshaun would be able to replace Gay’s production, and that there were plenty of “basketball reasons” for the trade. So it wasn’t just a financial decision; it was also a basketball one. Reading between the lines, at worst it’s a lateral move that saves money. At least this year anyway, as Prince is already beginning his post-30 decent.

Second, Hollinger’s own trade machine predicted the Grizzlies would be better after the trade, but that prediction is heavily influenced Ed Davis’ PER, and as I mentioned, Ed Davis has hardly seen the floor. If this trade were about Ed Davis, this is an awfully strange way of showing it.

Third, you could also say that Davis is a big part of Hollinger’s plans, but from a long-term rather than short-term perspective. We’ll see how they cross that bridge when they get there, I guess, but color me skeptical. It’s hard to see them committing long-term, significant money to Davis after making all these money-saving cuts, and young big men like Davis tend to get MLE deals or better off rookie scale contracts. In a league where Darko makes millions, Ed Davis probably will too. That whole short supply of tall people and all.

To be fair to Hollinger, Rudy Gay isn’t a superstar by PER. He’s had some good, but not great, seasons. Even if Gay is as good as his best PER season, it’s reasonable for Hollinger not to want to pay him max money.

But my critical question is still worth asking, because it highlights the critical flaw in PER: players like Rudy Gay – who score lots of points by taking lots of shots – get significantly overrated by it, and players like Tayshaun Prince – who don’t score tons of points but are competent players overall – get underrated by it.

And maybe Hollinger knows this.

I am certainly anxious to see more of what he does so we can find out.