Not to worry; this won't last says Myrtle

[Dentoman]

This thread makes my head hurt.
I have come to the conclusion that I am not anti-advanced stats ..... just too old and too tired to figure them out.

[Street Pharmacist]

Originally Posted by Enoch Root

It's not irrelevant though.

Shot blocking has become a defensive strategy. If both teams make 60 shot attempts and one team blocks 20 of them while the other team doesn't, the team that blocked 20 is in a good position to have given up fewer goals.

This is a situation where the game has changed. 20 years ago (probably even 10), a blocked shot would be considered essentially identical to a shot that missed the net - in both cases, it was simply a failed shot but if you kept doing it, presumably you would eventually hit the net or get it by the block and be successful.

But in today's NHL, blocking shots has become more and more of a defensive strategy. The Flames, as an example, collapse to the centre of the ice, allowing the other team to maintain possession at the perimeter. The strategy is to keep shots to the outside and to block as many as possible, reducing scoring chances that way.

It is simply a different way to play defense.

And the stats, as designed, haven't adjusted to it.

If all teams employed the strategy equally, it would be fine and the numbers wouldn't get skewed. But when teams are playing different strategies, and one strategy freely allows for more shots against, the stats as they are, will be miss-leading.

Having said that, the difference would be unlikely to be really massive - the question is: how significant is the difference?

I didn't say shot blocking was irrelevant, it's a legitimate strategy for less talented teams to win. It works.

However, corsi is a really accurate surrogate for possession. Corsi is used to measure possession. Blocking shots doesn't change this so why are we gumming up this stat? I think it's for people who think corsi implies which team is better, which it does not. A team with a good corsi and lousy defensive coverage and goaltending is still a bad team. Fenwick just seems like a "yeah we never have the puck, but we block shots!" kinds of stat. What exactly is it measuring????

[corporatejay]

Originally Posted by _Q_

I agree with this for the most part but I have to disagree that what's being quantified is accurate with regards to Corsi or Fenwick quantifying "possession". Those two stats quantify shot attempts and not possession, full stop. Sure, they can be used as a model to help understand possession, but they are not able to measure anything other than shot attempts. The only way to measure possession right now is to get a stop watch and time the number of minutes a team has possession of the puck during the game (and I'm sure some teams have employed that strategy).

For example, say you are trying to figure out how rich a group of 1000 people is, but for some reason, they don't want to tell you how much money they make. You find a correlation between wealth and the price of vehicle they drive. So you create a model in which you figure out what type of vehicle each one of those 1000 people drive and figure out where each one of them stands in terms of wealth. Sure it might make sense and it might be an accurate model for 95‰ of the population, but if one rich guy is happy driving a 1995 Accord or one not so rich guy puts all his money into a brand new Benz, then that throws everything out of whack.

Similarly, if a team employs a strategy in which they don't try to limit shot attempts, but try to limit scoring chances instead and instead of randomly firing pucks on net they hold on to the puck a bit longer in order to get into good scoring lanes, then it throws the whole corsi/Fenwick possession model out of whack as well.

In the vehicle wealth model, you can't say you're measuring wealth. By measuring the price of the vehicle you're measuring vehicle price and interpreting the data to figure figure out wealth.

Similarly, corsi/Fenwick aren't measuring possession no matter which way someone tries to spin it.

That's his point. Corsi and Fenwick SHOULDN'T be used to measure possession. People using them incorrectly are saying "Corsi is high therefore they are a high possession team".

What Enoch is saying is both Corsi and Fenwick measure, for lack of a better team, "Shots AT goal" (one with blocked shots, one without).

Stats guys have managed to conclude that measuring Shots at goal is a pretty good proxy for possession (i.e. someone who has a lot of shots at goal is more likely to be controlling the play).

Presumably this is a lot easier to calculate than using a stop watch, which is why people use them.

[calgarygeologist]

I haven't really looked into or explored the advanced stats but I'm wondering what the stats are saying about the Canucks? I certainly wasn't expecting them to be a top team and do the advanced stats point toward a regression or are they actually a legit team?

[GioforPM]

Originally Posted by calgarygeologist

I haven't really looked into or explored the advanced stats but I'm wondering what the stats are saying about the Canucks? I certainly wasn't expecting them to be a top team and do the advanced stats point toward a regression or are they actually a legit team?

The stats say they've played the Oilers 4 times already, so that's 8 easy points.

[Resolute 14]

Originally Posted by calgarygeologist

I haven't really looked into or explored the advanced stats but I'm wondering what the stats are saying about the Canucks? I certainly wasn't expecting them to be a top team and do the advanced stats point toward a regression or are they actually a legit team?

The Canucks actually look to be a bit of an odd bird. Their PDO is extremely low - 97.7 - primarily because they are getting the worst goaltending in the league at 5 on 5. .895 save percentage. Even Edmonton (.901) is better. The truth is, neither Miller nor Lack has been very good, and that suggests to me that the Canucks are incredibly lucky to be where they are. Miller, certainly, should not be 12-3. I expect that save percentage (and PDO) will come up, but I suspect their record will regress. Especially now that they don't get to beat up on Edmonton's defence every other game to cover that poor goaltending.

Their ES shooting percentage is around average, and they are 19th in CF% overall and 8th when the score is close.

If I had to make a prediction, they are a playoff calibre team, but a wild card team. Playing 20% of their games against the Oilers has masked a few problems.

[Tinordi]

The primary problem is that the people wielding them often don't understand how to utilize stats for analysis.

Who are these people? Alot of straw men being used by both sides of this debate. Of all the bloggers and analysts I read I rarely see people making deterministic arguments like you suggest. Most people go out of their way to qualify their conclusions using stats.

[Tinordi]

opendoor should opine on the Canucks...

[_Q_]

Originally Posted by Tinordi

Who are these people? Alot of straw men being used by both sides of this debate. Of all the bloggers and analysts I read I rarely see people making deterministic arguments like you suggest. Most people go out of their way to qualify their conclusions using stats.

Oh come on, you can't be that dense.

The whole premise behind the article in the OP is that the Flames will be out of a playoff spot because the advanced stats say so.

[SebC]

The Canucks are vastly outperforming their goal differential.

[EldrickOnIce]

Originally Posted by _Q_

The whole premise behind the article in the OP is that the Flames will be out of a playoff spot because the advanced stats say so.

No. The premise was their current level of play doesn't support them being at the top of the Western Conference.
Cheers to them defying the norm.

[EldrickOnIce]

Originally Posted by SebC

The Canucks are vastly outperforming their goal differential.

Simple answer: Oilers

[JetsFlamesFan]

Originally Posted by BACKCHECK!!!

We're not trying to predict "everything".

We are predicting ONE thing.

That the Flames are not going to finish the season in 2nd place in the Western Conference.

So are we basing that on the fact that their shooting percentage is so high, and it must average out over 82 games? If that's the case, is their shooting percentage so high because their shots on goal are so low and they are just getting lucky right now? If they are way below average in shots on goal, couldn't I also suggest that their shots on goal will go up because it must average out over 82 games? And if they take more shots, the quality of those shots will will probably diminish bringing down their shooting percentage but with the overall goal production remaining steady? And what if it is a deliberate strategy like the previous poster said? If there is a higher chance of scoring from a certain area of the ice and they forfeit all their opportunities from the other areas of the ice in favour of getting to the higher scoring areas, then their goals may not go down. That would be dependent on the other teams being able to keep them out of those scoring areas, and so far I don't think any team has been able to do that to the Flames except maybe St. Louis. I'll be honest and say I haven't really done a lot of research into the stats, I'm just trying to think about it logically, and reading off what other people are posting. I'm probably wrong, I almost always am, but I think the Flames were able to do what they wanted to do last night in spite of the loss. It's just that Chicago did what they do even better. I do agree with you, I'm not of the opinion that the Flames will keep it up and finish 2nd in the conference and I never said that I thought they would, but I'm also not of the opinion that they will fall off the face of the earth like some of my friends think. I think the only way we don't make the playoffs is if a) our goaltending goes sour or b) Giordano, Brodie have a significant injury. Just my opinion

[edslunch]

Originally Posted by corporatejay

Fenwick just thinks that Corsi is meant to be a proxy for scoring chances, not play control per se. This is why he omits blocked shots.

My argument is basically: 1. The whole (or perhaps best) use of Corsi is to have objective figures that can be used as a proxy for scoring chances (what else are you using it for?).

2. A shot that is blocked is either a) not a scoring chance at all, or b) on average from a worse scoring area than shots/posts/missed shots.


He wrote that in 2007, and I feel like 7 years later there are a lot more blocked shots, even those from the slot, so I'm not sure how useful argument 2 is anymore.

Are we trying to measure scoring chances or possession? I think possession, in which case even for a blocked shot you possessed the puck, so it should count.

[edslunch]

Originally Posted by corporatejay

That's his point. Corsi and Fenwick SHOULDN'T be used to measure possession. People using them incorrectly are saying "Corsi is high therefore they are a high possession team".

What Enoch is saying is both Corsi and Fenwick measure, for lack of a better team, "Shots AT goal" (one with blocked shots, one without).

Stats guys have managed to conclude that measuring Shots at goal is a pretty good proxy for possession (i.e. someone who has a lot of shots at goal is more likely to be controlling the play).

Presumably this is a lot easier to calculate than using a stop watch, which is why people use them.

I'm sure people would switch to stopwatch time in a heartbeat if it was available. Put a tracking chip in the puck and on each player plus a bit of software and you could get a much more accurate assessment of possession. In the meantime shots may be the best we've got

[Fighting Banana Slug]

Not sure why people are defensive about these stats and the conclusion that the Flames will likely regress. This is a good test to see if there is any validity to the predictive power of the stats. Fair to question whether Fenwick or Corsi is a better proxy for possession, but ultimately, these would have value if it is a better predictor of future success, than current W-L.
What worries me about this discussion, is that many are sounding much like Leafs fans did last year. "Sure the stats are bad, but that is because our system creates high grade shots", or "Our goalies can sustain the save percentage, because our defensive system allows more low grade shots". Neither of those held out, and the stats argument proved correct. Same thing happened a few years prior with the Minny starting strong.

[Jay Random]

Originally Posted by Fighting Banana Slug

What worries me about this discussion, is that many are sounding much like Leafs fans did last year. "Sure the stats are bad, but that is because our system creates high grade shots", or "Our goalies can sustain the save percentage, because our defensive system allows more low grade shots". Neither of those held out, and the stats argument proved correct.

The same argument was made about the 2003-04 Flames (who had a deliberate strategy, after Kiprusoff arrived, of letting teams shoot from the outside and clearing the path so Kiprusoff could see them to make the save). In that case, it turned out that the save percentage and GAA were sustainable – all the way to game 7 of the finals. So there are examples on both sides. Which side this year's Flames will fall on is precisely what is in question, and you can only deny the doubt by denying that the other side exists.

To start by making an argument from statistics, and then suddenly do a 180 and finish your argument with pure anecdotes about the Leafs one season and the Wild another season, is too acrobatic for my taste. My head hurts. There are many ways to make an argument from statistics, but this is not one of them.

[Fighting Banana Slug]

Originally Posted by Jay Random

The same argument was made about the 2003-04 Flames (who had a deliberate strategy, after Kiprusoff arrived, of letting teams shoot from the outside and clearing the path so Kiprusoff could see them to make the save). In that case, it turned out that the save percentage and GAA were sustainable – all the way to game 7 of the finals. So there are examples on both sides. Which side this year's Flames will fall on is precisely what is in question, and you can only deny the doubt by denying that the other side exists.

To start by making an argument from statistics, and then suddenly do a 180 and finish your argument with pure anecdotes about the Leafs one season and the Wild another season, is too acrobatic for my taste. My head hurts. There are many ways to make an argument from statistics, but this is not one of them.

If the stat guys said that the 2003-04 Flames success was unsustainable based on stats, then point taken, but I don't recall any discussion of that 10 years ago. My recollection is that they were saying that based on the eye test, but if you have a link I would certainly like to see it.

There is no 180 in my post. What I said was the arguments against advanced stats in the Leafs and Wild case are very similar to what I am reading here (purely anecdotal, not stat based). Those arguments were not supported by the advanced stats and proved wrong. My point is that the advanced stats crowd provided a hypothesis, the reaction was similar to what we see here, and the advanced stats proved correct.

[PeteMoss]

Flames had a positive Corsi in 03-04 but did have a higher than normal PDO (although not crazy high)

[PeteMoss]

Best Flames team in terms of Corsi in recent history is 08-09 (03-04 forward). They finished 5th in conference in got beat out by Chicago in 6 games.