I love (and I mean love) statistics. I really buy into most baseball sabermetrics. Corsi has its uses, but any hockey statistic (traditional or otherwise) must be taken with a grain of salt. Events in hockey aren’t isolated, but have tons of variables interacting at once, much like most defensive metrics in baseball (thus why articles on fangraphs often also reference the fans’ scouting report to corroborate any defensive metrics they use). Over the long-term, things should normalize (though players’ abilities, linemates, and match-ups are not going to remain static), but short-term stats like this is pretty much worthless. Even to try and note “short-term trends.”

The “trend” is that Roy Halladay is not only the greatest playoff pitcher of all time, but a better hitter than everyone on the Cincinatti Reds.

Heck, the numbers don’t even support the argument that MP85 is better than MaJo defensively. Both gave up 53 scoring chances (and MaJo even played 3 more minutes of time), so the defensive aspects of Corsi were the same. It was only in the chances generated (the offensive aspects), that MaJo lagged behind.

I realize this is all the data that is available, but at this point the data set is just too small to have any value. A 3rd line center is probably going to play around 850-1000 minutes over the course of a season. Using a 60-minute sample size (even in the regular season, much less the pre-season) would be the equivalent of using roughly 2 starts to analyze a starting pitcher in baseball. It’s just not going to provide any meaningful information.

Notice that Sami Pahlsson consistently plays some of the toughest minutes in the league. He’s exclusively used in a checking role with other checking line players.

Marc Andre Bergeron plays some of the easiest minutes in the league, with easy zonestart as well. You’re plucking Corsi out of thin air, without looking at quality of competition, quality of teammates, and zonestarts.

People discount plus minus because it’s without context. Corsi has context, but you’re being blind to it right now, and hence it seems bad to you. Find me a real example.

Also, you’re not understanding that Neil just said thus far Perreault seems to be better. He’s not drawing any conclusions–just pointing out the short-term trend. It’s exactly the same as calling Jordan Eberle “clutch.”

@SantaC–that reasoning would put 18-year old goalie Jack Campbell as the starting goalie for the Dallas Stars right now.

@strungout–the Buffalo Sabres were the ones who started keeping track of Corsi. I’d say they think it’s helpful. The NHL teams probably also have loads of video data and advanced stats we don’t have.

Corsi is not a causation of anything. It’s an indicator that correlates pretty strongly to winning. Once people like you get over this phobia of all things non-traditional then you’ll see how useful it is. It showed me that Marc Staal is a top-5 shutdown defenseman, Duncan Keith is flat-out the best defenseman today, that Tomas Fleischmann is overrated, that Eric Fehr is a good hockey player.

@Neil–it’s pretty much impossible to drag Alex Ovechkin down. Brooks Laich, on the other hand, doesn’t drive Corsi; he’s more of a passenger (and to be fair, so are guys like Holmstrom and Knuble).

On the other hand, you’re probably right that MP is better than MarJo defensively right now. I don’t know if you’ve read Copper and Blue’s “Unrealistic Expectations” piece, but it’s worth a read if you haven’t.

For you doing whatever it is you do? Maybe. But for real NHL teams making actual decisions on playing time and player development…utterly useless.

And you cannot possibly disagree that a team’s chances of winning improve if they’re playing more of the game in the offensive zone.

Hell, Marc-Andre Bergeron was in the top 10 amongst all players with 10+ minutes of 5-on-5 and 60+ games in 2008-09. Peter Regin and Carlo Colaiacovo were second and third this past season.

Many discount +/- as a relevant hockey statistic, why not Corsi? Because it has a fancy name?

And no, the Corsi ratings for MJ and MP this preseason don’t give any context whatsoever, because the sample sizes are statistically meaningless. I know I sound like a broken record, but it’s the major flaw with the analysis. It’s like trying to determine who’s the better hitter by looking at the statistics for 15 at-bats in spring training.

Like any statistic, it provides context – and you discard it at your own peril. As for Alfreddson: he is 37 and clearly on the downside of his career. His Corsi value from last year is not good but that doesn’t mean we discount his other 13 seasons of play.

“the sample size is too small to make the statistics meaningful.”

I would argue that I used ALL the preseason data available to make a conclusion. Granted, in a perfect world I would love to have all the data for SEL, AHL and NHL available, but that wasn’t possible. Would I use 60 minutes of 5v5 TOI to project the careers of centermen? Nope, but does it provide that much more clarity of how they used their opportunity.

@RedArmyLine “the fact MP played with AO is critically important since AO is one of the best Corsi forwards in the NHL”

The fact MP85 played on the 8-22 line AND had positive Corsi means something. Does it mean he is a top line player? No, but it *does* mean he didn’t drag the line down. MJ90 dragged a line of Fehr/Chimera and Fehr/Laich down to negative numbers.

Again, it is important to remember that this is pre-season and stats like these only provide context. Am I saying Perreault is going to be the next coming of Datsyuk? Of course not. Am I saying he will be a better long term player than MJ90? Not at all. All I am saying is that based on the preseason numbers MP85 should have gotten a shot (at the very least over Hendricks – how many 28yo rookies amount to anything? Mark Streit and ????) but didn’t under the guise of MJ90 being better defensively long term.

-Neil

Also,
“So is MJ90 better defensively? Too soon to tell, but to this Corsi-aware blogger it looks like MP85 was sent down because he could be and not because he is an inferior defensive player.”

“Too soon to tell” sounds to me like just noting what the trend of the results thus far have been, not a conclusion.

Neil,

I don’t think scoring chances and Corsi are interchangeable in such small sample, and the fact MP played with AO is critically important since AO is one of the best Corsi forwards in the NHL (as far as I know only Datsyuk and Zetterberg are better). The Capitals actually kind of lack such Corsi-driving forwards; AO, Backstrom, Semin, and Fehr all get the job done, but aside from them guys like Laich, Flash, Chimera, and the fourth line don’t really drive the play as much and as such Johansson’s Corsi would suffer mightily playing with them.

Statistics should represent a players’ abilities over the long term, but in a short window such as the pre-season, they’re not always going to. You can, and players frequently do, have bad stats despite playing well or good stats despite playing poorly.