Sunday, December 20, 2009

Even Strength Data for Games 1-500



As a continuation of a previous post, I figured that I'd throw up EV data for the first 500 games of this season.

I've included both overall EV data, as well as data on even strength play with the score tied. Empty net goals have been excluded.

The first sheet shows data for games 1-500, the second for games 1-252, and the third for games 253-500. I've also included a fourth worksheet that compares each team's corsi ratio with the scored tied from the 1st half of the year (games 1-252) to the 2nd half (253-500).

Some comments:

It pains me to admit it as a Habs fan, but Gabe Desjardins is absolutely correct -- the Canadiens look like a terrible team by the numbers. Over the last 250 some games, the Habs have had the worst corsi ratio in the league at EV with the score tied, and by a large margin at that. The scoring chance numbers don't look any better.

To make matters worse, the Habs have also been getting bombed on special teams. In the same 250 game period, they've given up almost twice as many shots on the PK as they've accumulated on the powerplay (55 vs. 98). In fairness to Montreal, that has more to do with their league worst penalty differential than it does with special teams performance per se. In any event, the numbers aren't good.

Curiously, the team's underlying numbers were actually quite respectable over the first 250 some games. It'll be interesting to see where they end up.

On the other side of things, the Ducks appear to have improved considerably at EV relative to the first 250 games. While their current record may not be impressive, they're definitely trending in the right direction. If they can find a way to take fewer penalties, they should be able to at least compete for a playoff spot.

Phoenix continues to perform well at EV. The season is almost halfway over at this point and the Coyotes currently have the 2nd best corsi ratio in the league when the score is tied. This is surprising considering that they were 28th last year in this regard.

I'm not entirely sure on how to account for their turnaround, although I suspect that it boils down to two things. For one, they've gotten rid of and/or sent to the minors a lot of guys that were really hurting them last year (Turris, Lindstrom, Hale, Fedoruk, Lisin, Porter, and Carcillo). The replacements -- Lombardi, Prucha, Fiddler, Lang, Vandermeer, Aucoin, and Vrbata -- are demonstrably better hockey players.

Secondly, I think that the coaching change has likely had an effect as well. Tippett's teams in Dallas were consistently able to outshoot the other guys, both at EV and overall. While it's hard, if not impossible, to quantify his contribution, I think that it's safe to say that he's an upgrade over a relatively inexperienced Gretzky.

11 comments:

Olivier said...

The annoying part for the habs is the complete disparition of their ability to shoot the puck at the opposition's net (and thus drive possession). They actually are in the top ten for shooting %, so you can't say they were unlucky there. I'm surprised at how low a .917 ESsv% ranks them tough.

Sunny Mehta said...

fantastic stuff, jlikens.

correlation between EV tied corsi and EV corsi is r= .91


here are some correlations between 1st 250 EV tied stats and 2nd 250 EV tied stats

corsi ratio: r= .58

(not bad for such small samples.)

Sh%: r= .26

corsi Sh%: r= .32

(i'm kind of surprised it's that high. too much noise here to conclude anything definitely though.)

Sv%: r= 0

corsi Sv%: r = .17

(i'm going to reiterate my stance that all Sh% and Sv% numbers should use total shot attempts as the denominator)


with all this stuff, the samples are just way too small right now, but if you keep posting these updates every 250 games, I think we're gonna learn some cool stuff by season's end.

Sunny Mehta said...

it's interesting because using the 08-09 EV tied data, i get the following correlations between first half of the season to second half of the season

corsi ratio: r= .75

corsi Sh%: r= .1

corsi Sv%: r= .19


Vic found similar numbers iirc, and his study was more in-depth.

Sunny Mehta said...

also, if we consider special teams ratio to be (PP corsi for)/(PK corsi against), correlation between 1st 250 games STR and 2nd 250 games STR is r = .52

JLikens said...

Sunny:

Yeah, I too noticed that there was a correlation between the 1st and 2nd halves of the sample in terms of EV SH% with the score tied.

I also noticed that the standard deviation for the entire sample was 0.0195, which seemed a little high to my eye.

I decided to do some simulations (50 simulations, to be exact) in order to determine what one would expect to see on the basis of chance alone.

The results:

Average STDEV: 0.01586

# of Seasons where STDEV was greater than 0.0195: 4/50 (8%)

So there's roughly an 8% chance that the standard deviation would be that wide or wider by chance alone.

This, of course, differs from what was observed in 0708 and 0809, where the STDEV in some 55-60% of the simulated seasons was broader than the actual STDEV.

Of course, we're not even halfway through the season yet, so I'll refrain from concluding anything at this point.

In terms of using total shot attempts in calculating SH and SV%, I agree that that's probably an improvement over the current method, what with the home recording biases and what not.

I plan to look at the subject of shot recording bias in greater detail in the near future in order to determine which rinks are truly undercounting or overcounting shots.

JLikens said...

Olivier:

Yeah, it's definitely frustrating to watch.

The Habs haven't iced a team that outshot the opposition with the score tied at EV since 2003-04. And before that, you'd likely have to go back as far as 1997-98.

I was hoping that would change this year, but it's just not going to happen.

Sunny Mehta said...

J,

what happens if you run that sim for ev tied corsi Sh%?

i'm seeing an observed stdev of .0108 is that what you see too?

JLikens said...

Yeah, I get the same observed value of 0.0108.

Simulation Results (50 simulations):

Average Expected STDEV: 0.0083

In none of the 50 seasons did the expected STDEV exceed the observed value of 0.0108.

The greatest expected STDEV in any of the simulated seasons was 0.01075.

Sunny Mehta said...

whoa

Hawerchuk said...

Phoenix's improvement is surprising to me. But that's because I think I (we?) discount defensive skill too much, or just do a terrible job of evaluating it. I knew Fiddler and Aucoin would help, but losing Sauer after one game and replacing him with Jovanovski should have hurt.

But generally, I think I agree with you - Phoenix added a bunch of players who actually play defense, plus Vrbata, who has played well, and everything has turned out way better.

JLikens said...

You're right in that defensive ability at the player level is poorly understood and difficult to quantify.

Vic had a great post from a while back that examined the effect of individual players on EV shooting and save percentage. He found that while individual players were able to affect their on-ice EV shooting percentage to some degree, the same was not true of save percentage. More specifically, there was no difference between 1st, 2nd, and 3rd pairing defensemen in terms of on-ice EV save percentage. Of course, the fact that 1st pairing D-men play against tougher competition (i.e. forwards with better on-ice shooting percentages) than lower-pairing D-men implies that there is some affect, just not much.

That being the case, it seems that the best way for individual players to prevent even strength goals against their own team -- at least over the long run -- is through keeping the puck out of their own zone. The Coyotes have definitely excelled in that regard thus far.