Ilya Bryzgalov and the Shootout
There are currently 26 NHL goalies who have faced at least 100 shootout attempts.
Confirmation bias dominates one's reading of the list; the person who follows the natural assumption that some goalies are better at shootouts than others will point to Pekka Rinne being first on the list and Henrik Lundqvist being fourth as supporting evidence for their argument. The person who is out to prove that shootouts are random will point to Johan Hedberg being second on the list, Mathieu Garon fifth, and Rick DiPietro sixth.
Ironically, both sides probably think that Marc-Andre Fleury being third supports their point of view.
So instead of doing this anecdotally, let's look at the data.
Here's the relationship between career save percentage and shootout save percentage:
Save percentage during play is worthless as a predictor of the shootout; Rinne and Lundqvist are the only goalies to have a really high save percentage both in normal play and in the shootout. So pretty much every team but two has had to come to grips with the idea that their goalie won't be great in both situations, and I can promise you that the fans of the Devils, Lightning, and Islanders don't consider "good in shootouts" much of a consolation prize.
Moreover, Ilya Bryzgalov isn't even particularly bad at shootouts. At 63.2%, he's slightly below the 67.7% league average (if you were wondering, that dot down at 56.3% is Niklas Backstrom). Yeah, giving up 8 goals on 10 attempts this year is atrocious, but the fact that he could be a 66% goalie for his career up to now and then 20% so far this year just underscores what a small sample size we're worrying about.
It is natural for a Flyer fan to focus more on the four games that they saw than the multiyear career in Phoenix, but a rational look at whether he is genuinely bad at shootouts would have to weight the multiyear career more than those last ten shots. Being incredibly frustrated that the team keeps losing shootouts is reasonable; panicking about it and calling for the Flyers to bring in a relief goalie for the shootout is not.
Bryzgalov is going to eat up a lot of cap space for a long time and hasn't been very good so far in any phase of the game. There are plenty of much more humongous big fish to fry than those four shootouts.
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Flyers need to win in regulation
They played very well last night but still have such difficulty scoring. Reimer went down way early like bryz and bob but we did not make him pay for that. we shot low. Also in the shootout bryz has not been good but neither have the shooters. If you are tired don’t shoot or tell me why you are shooting and skating right down the middle with no move. You have to make a move bottom line. And I watched the game closely last night and see a big problem with our team. The flyers offensive players get back but they don’t defend they try to defend space and then chase. I saw three guys on one goal chase one guy and he did not score lol. coburn was owned by lupul, you have to clear the crease boys. The plus in all of this, was the last 6 minutes in the third. That was some of the best hockey i have seen from the flyers all year.
by whosyourjockey on Feb 10, 2012 11:16 AM EST reply actions
They played very well last night but still have such difficulty scoring.
The Flyers are second in the league with 3.26 goals per game. I don’t think they have difficulty scoring.
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by Geoff Detweiler on Feb 10, 2012 11:22 AM EST up reply actions
Obviously that's skewed by Winnipeg letting them score 8 in a game
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Broad Street Hockey - Covering the Philadelphia Flyers. Have you accepted Ilya Bryzgalov as your savior?
by Travis Hughes on Feb 10, 2012 12:31 PM EST up reply actions
Hey, if Jeff Carter taught us anything, it’s how to pad your stats with meaningless goals.
Lightning strikes once, Hextall strikes twice!
"I think there is virtue in pissing off idiots." - Fehr and Balanced
by hintzy64 on Feb 10, 2012 12:32 PM EST up reply actions 3 recs
This showed up as non-sarcasm font on the SBN app and I was confused as to whether or not you were serious.
by everybodyhitswoohoo on Feb 10, 2012 3:34 PM EST up reply actions
2.54 combined goals per game against Rangers, B’s, Devils, Pens (elite teams- and I know this can be argued, obviously). And I know one can argue, “well of course goals per game will go down when playing the league leaders,” but I’m really just pointing this out for consideration to show what that goals per game number is really like when facing some good squads, no doubt, teams we’ll have to get trough to reach the cup (knock on wood)
For you guys and girls that live and breath this stuff on a whole another level than I do, does 2.54 g/g seem low or high against solid teams, or just warm enough for mamma bear? Obviously we’d all love it to be 10 g/g, but does 2.54 stand out to you in any way?
"It's not the size of the dog in the fight, it's the size of the fight in the dog" -Michael Vick
Season-long GA/G for those four teams are:
NYR – 1.96
BOS – 2.23
NJD – 2.76
PIT – 2.56
(avg – 2.38)
It’s somewhat of a crude comparison, since I’m mixing Flyers combined against those four teams with those four teams individually vs the league, but we score more goals against NYR and BOS than they typically allow, slightly less than NJ’s average, and pretty much even with the Pens’ average. That at least suggests we’re also an elite team and challenge them more than other teams, doesn’t it?
Lightning strikes once, Hextall strikes twice!
"I think there is virtue in pissing off idiots." - Fehr and Balanced
they do struggle to score i am sorry
with the amount of shots they get they should have way more goals that is the problem.
by whosyourjockey on Feb 10, 2012 7:06 PM EST up reply actions
I think your memory is overweighting recent games where they got a lot of shots and didn’t score.
The Flyers have a shooting percentage of 10.0%, fifth in the league. That’s just as big a part of their #2 offense as their shot rate (also fifth, at 32.6 per game).
In fact, if you lower their shooting percentage to league average, it costs them 0.36 goals per game, while lowering their shooting rate to league average only costs them 0.27, so I would argue that their shooting percentage is a bigger factor in their high goals per game rate.
In other words, they’ve been very good both at generating shots and at having more than their share of those shots go in. The problem has been at the other end; they’re 23rd in goals against per game.
@BSH_EricT
Writer at Broad Street Hockey
Not only what Eric said, but the Flyers are 5th in the league in shots per game and 2nd in the league in goals per game. Don’t know how you can say they aren’t efficient enough.
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by Geoff Detweiler on Feb 10, 2012 7:22 PM EST up reply actions
Given that the numbers don’t match up with this, I wonder if part of it is a mental adjustment to the fact that the team sucks in its own end. Once you admit the defense isn’t doing it then the only way to win is to score more. When we don’t win it’s because we haven’t scored enough. We ignore what we’ve given up on and are only disappointed by what we still hope for. When I used to be a baseball fan I’d hear a version of this with pitching and hitting.
/s, more often than not
by flyersfaninchicago on Feb 10, 2012 7:28 PM EST up reply actions
Right. Let’s not forget the Flyers have scored 4 goals in three of their last five games. They’ve scored 3 goals or more in eight of their last thirteen.
The problem is that they’ve given up 4 goals or more in five of their last twelve. It just doesn’t mesh with reality.
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by Geoff Detweiler on Feb 10, 2012 7:32 PM EST up reply actions
i think
There’s also a lot of pressure on him because we rarely score in shootouts..atleast when I watch. I can imagine he’s over thinking things because he’s always getting burned so bad but if lavy can stop picking Simmonds to shoot and they score more it will take a lot of pressure off Bryz
by FLYERS_ALL_DAY on Feb 10, 2012 11:16 AM EST via mobile reply actions
Flyers shooters have scored 5 times out of 17 tries, or 29.4% of the time. League average this year is 33.11%, it was 30.59% last year, and 32.12% the year before.
Or, the Flyers are barely below league average shooters.
Bryzgalov has stopped 2 of 10, or 20%. League average is 66.89%.
Simply put, Bryzgalov should not feel any extra pressure since the Flyers are basically average in shooting. If he does feel pressure, it’s on him and not the shooters.
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by Geoff Detweiler on Feb 10, 2012 11:26 AM EST up reply actions
Just out of curiosity, you give the league average for shootout scoring, what’s the standard deviation? Is it a fairly close grouping and the Flyers are an outlier, or is it a wide distribution and the Flyers are close to (but slightly below) the average? I don’t know why it’s never occurred to me to ask this before, but you described both Bryz and our shooters as being slightly below average, so it made me wonder if “slightly” is in the eye of the beholder. :-p
Lightning strikes once, Hextall strikes twice!
"I think there is virtue in pissing off idiots." - Fehr and Balanced
I honestly don’t know. I don’t think that’d be easy to find, so I don’t see myself doing the work :)
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by Geoff Detweiler on Feb 10, 2012 11:59 AM EST up reply actions
I presume you plugged all the numbers into Excel to work out the league average? Just use =STDEV and you get the standard dev
Simon Gagne AND Mike Richards may move between towns, wear new jerseys and call different arenas home but, at the end of the day, they will both always be Philadelphia Flyers.
One day Sean Couturier will win the Conn Smythe. You heard it here first.
by PursuitOfLappyness on Feb 10, 2012 7:45 PM EST up reply actions
Would you like to do it? Otherwise I could just plug in the numbers myself, because I’m curious too
Simon Gagne AND Mike Richards may move between towns, wear new jerseys and call different arenas home but, at the end of the day, they will both always be Philadelphia Flyers.
One day Sean Couturier will win the Conn Smythe. You heard it here first.
by PursuitOfLappyness on Feb 10, 2012 7:46 PM EST up reply actions
Actually, the NHL has all-time team stats. I didn’t realize that despite being there a minute ago.
It wouldn’t be hard to find the data, but I still don’t care to do that work :) Saying Bryz feels pressure and that’s why he sucks isn’t going to be countered with “their standard deviation from the mean suggests that they are quite average.”
:p
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by Geoff Detweiler on Feb 10, 2012 12:02 PM EST up reply actions
Hahaha, fair enough. I guess I’m just wondering if being 3.71 percentage points below average is a significant amount or not. You say “barely below average”, but to me that sounds larger than that because I imagine that the teams would be clustered fairly closely in shootout percentage. I’d be surprised if the variation from the best to worst teams would be that large.
Lightning strikes once, Hextall strikes twice!
"I think there is virtue in pissing off idiots." - Fehr and Balanced
It kinda doesn’t matter though. A couple percent below average is going to mean about a point per year — it doesn’t really matter whether there are teams giving up (and getting) more than that or whether a point per year is more than anyone else gives up or gets; it’s still just a point per year.
@BSH_EricT
Writer at Broad Street Hockey
And I’d be wrong, I went to nhl.com to look it up myself (gasp!) and there is a rather large spread. So far this season, NJ shoots 55.6% and TB shoots 14.3%. Flyers are 18th, just below the middle.
Lightning strikes once, Hextall strikes twice!
"I think there is virtue in pissing off idiots." - Fehr and Balanced
and TB shoots 14.3%
Good thing they have Garon to bail them out.
@BSH_EricT
Writer at Broad Street Hockey
And they have Stamkos
Who was complaining (sort of) about not being used in the s/o during the All-Start competition. And won the breakaway competition.
Small sample and all, but if you’re Guy Boucher, why do you NOT use Stammer in shootouts much?
by Georgia_Flyer on Feb 10, 2012 1:11 PM EST up reply actions
Stamkos is 0-3 this year. He was 0-7 last year. He is 4-24 for his career.
I can understand the perspective that his long history of scoring lots of goals during play might tell you more than 24 shootout shots. But it’s also reasonable to say that his goals often come from things like positioning and a quick release more than puck-handling and that his terrible shootout results might be more relevant.
@BSH_EricT
Writer at Broad Street Hockey
That was pretty funny. So he’s been in the doghouse since then, eh?
Kovy famously lost the puck on a shootout, too – and he’s tearing them up this year. He got forgiven.
by Georgia_Flyer on Feb 10, 2012 1:32 PM EST up reply actions
Haha I doubt it, I would assume more of what Eric has said; but I enjoy that video because, well, how often to you see a player lose his edge in a shoot out or penalty shot at that level.
being obnoxious and self righteous while ignoring the point since 9/29/11
a rational look at whether he is genuinely bad at shootouts
At “rational view on shootouts,” you lost about 75% of Flyers fans.
Keeping alive the old Vaudeville joke, "I'd rather be dead than play Philadelphia."
Be Glad
Good analysis.
But be glad because this is a playoff team and one of our (perceived) biggest weaknesses will not matter when we are in the playoffs. Winning these games only improves the playoff seed. This team has been better “when it matters” as lower seeds and on the road anyway. Right?
I know it’s completely anecdotal but from the small amount of highlights I’ve seen of Bryz in Phoenix it looks like he was a lot better with the poke. It seems the vast amount of times he has gone for the poke here in Philly it always seems to burn him. Maybe teams have scouted this? I could also be making this entire thing up.. Either/or.
What, Eric, no one told you? Dave Tippett’s system included lining the path between the goalie and shooter with defensemen on penalty shots.
by everybodyhitswoohoo on Feb 10, 2012 12:03 PM EST via iPhone app reply actions 2 recs
See, that’s the kind of insight you don’t get from a stat sheet. Glad someone watched the game.
@BSH_EricT
Writer at Broad Street Hockey
Nah, Bryz just used the water-bottle trick.
by Georgia_Flyer on Feb 10, 2012 1:13 PM EST up reply actions
Soccer vs. hockey
Bryz says he feels like he’s defending a soccer net, which makes me wonder…..is a SO (hockey) goalie required to be the same one who closed the game? In soccer, it can be any of the players on the pitch at the last whistle. I ask this because I would love to see Bryz yield to Bob in the event of a shootout. Bob goes through the effort of dressing out, so why not let him get a little muddy? Plus, he’s a good dancer.
by Lesion of Doom on Feb 10, 2012 12:26 PM EST reply actions
Bob has stopped 52.2% of shootout attempts in his career.
Bryz has stopped 62.3% of shootout attempts in his career.
Why would you bring in a cold goalie who has so far been worse at shootouts?
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by Geoff Detweiler on Feb 10, 2012 12:29 PM EST up reply actions
Because he stopped all of Florida’s attempts! Recent memory trumps your silly career numbers!
Lightning strikes once, Hextall strikes twice!
"I think there is virtue in pissing off idiots." - Fehr and Balanced
I understand the stats and agree that bringing in a cold goalie doesn’t make a lot of sense, but if the improbable SO losses continue to pile up at Bryz’s expense, then it couldn’t hurt to try. Bryz has been playing a lot better recently though, hopefully his slump is over.
Jagr shoots, Jagr scores!!!!!!
Name your poison: a tired starter or a cold reliever. But Bryz’s earlier comment about “not liking shootouts” still gnaws at me. As a soccer goalie, I loved PKs — and that’s without being allowed to creatively freelance in the “crease.” But back to the question: would the rules allow a SO switch?
by Lesion of Doom on Feb 10, 2012 12:34 PM EST up reply actions
Yes, the rules allow it.
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by Geoff Detweiler on Feb 10, 2012 12:35 PM EST up reply actions
I play this from the perspective of both goalies. If I’m Bryz, I go “phew!” and readily relinquish to someone who’s hotter (these days) in SOs. If I’m Bob, I smile and say “watch this!” But Einstein’s definition of madness applies here, and we really need to try something different. (The introduction of SO practice is one encouraging development.)
by Lesion of Doom on Feb 10, 2012 12:44 PM EST up reply actions
They only need to try something different if you think Bryz will continue to stop fewer than 55% of shots. And since he stopped 66% up to this year, I don’t see why you would think he’s going to be worse than Bob going forward.
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by Geoff Detweiler on Feb 10, 2012 12:51 PM EST via iPhone app up reply actions
All I know is that against the Leafs, my half-empty glass said “they might get the fourth goal to tie”, and my half-full glass said “well, if it goes to SO, we still have a chance with Bob.” Bryz looks lots better in regulation lately, though, so maybe the SO stuff will be moot.
by Lesion of Doom on Feb 10, 2012 1:09 PM EST up reply actions
Unfortunately, They no longer allow you to pull the goalie in a shootout.
Thanks, Roger.
"Because wives and girlfriends aren’t on the road."
by BannedStreetBully on Feb 10, 2012 12:44 PM EST up reply actions
It could be really dangerous to send a cold goaltender out to face breakaways. If he has been sitting all night on the cold bench and has to throw a full split on a deke his groin is shredded for the remainder of the season. Soccer is completely different in the flexibility that is required to make a save.
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DISCLAIMER: Information written above may not be entirely factual nor provable with the use of complex statistics. But it may induce thought, humor and possibly laughter.
It takes pretty awesome data to get an R^2 of .0001
Also MAF sucks.
OPERATION TANK IS A GO. It’s the only explanation for Mike Weber. He’s on a secret mission.
It takes pretty awesome data to get an R^2 of .0001
Wow, almost as good as Department of Commerce data. Or how consumer confidence data predicts gross domestic product.
Also MAF sucks.
And it’s always good to know that Sabres fans and Flyers fans can find areas of consensus and collaboration.
GMAT verbal section question, Philadelphia sports version.
In 2015, which one of the following will prove to be a better investment?
(a) Ilya Bryzgalov's contract (b) Ryan Howard's extension (c) Mike Vick's extension (d) Greek bonds from 2009 (e) Papelbon's bloat deal
/DiPietro'd
Maybe Bryz would have a better shootout save % if he was willing to rip his groin, break a bone, or otherwise sacrifice his health to make each save.
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- @ScottieUpshall (July 1, 2011 2:15pm EST)
Another Way to Slice the Data
Interesting analysis – Thanks for your work on it.
In looking at the graph, a few things struck me: (1) that there are only 26 data points in the sample and (2) that one or two extreme points can really influence the slope of a regression line with that few of data points. These observations got me thinking of whether a few outliers (of one or two goalies of the 26) might be masking a more general relationship.
Rather than just be satisfied with idle curiosity, I dug into the data a bit more to see what would happen if the sample size was increased, which will decrease the effect of any particular data point. Thus, I sliced the data to look at goalies who have faced at least 50 shootout attempts (instead of the criterion of 100), which increases the sample to an N of 47 (and includes goalies such as Ward, Howard, and Halak that were excluded with the original number of shootout attempts criterion of 100).
When you make this simple change (to 50 attempts instead of 100 attempts), there is a positive relationship between career save percentage and career shootout save percentage – The correlation between these variables is .22. This relationship (r = .22) is small and ultimately doesn’t account for much variance. Further it is not statistically significant, although it approaches significance with a one-tail directional test (p = .07) – This lack of significance is mainly due to the low statistical power given the small sample size.
Overall, I personally think this reanalysis does show that there is some positive relationship (albeit a small one and one that only approaches significance) between career save percentage and shootout save percentage when you expand the data to include a more liberal criterion of 50 shootout attempts. In my opinion, based on this reanalysis, the relationship is indeed small (r = .22), but it is far from "worthless" in understanding shootout performance.
As a postscript – I understand that one could argue that the cut point of 50 shootout attempts is not stable (and that is why 100 shootout attempts should be used); however, this unreliability of the measure could actually work against the magnitude of the relationship such that the correlation would be larger if I corrected for the unreliability. Further, I personally feel that the tradeoff in terms of the positive of almost doubling the sample size and increasing statistical power is worth any potential negative associated with this potential unreliability. I understand that one always needs to make decisions about how to slice the data and reasonable people can disagree as to the best way to do it. Just my attempt at another way to look at things.
(1) that there are only 26 data points in the sample
Fewer data points tends to increase the correlation, not decrease it, right? If we don’t see any correlation between the data points where we have the best sense of the player’s talent, why would you expect a stronger correlation by adding in a bunch of players whose talent is even less well-known?
(2) that one or two extreme points can really influence the slope of a regression line with that few of data points
When the R^2 is 0.0001, you can draw a line with any slope you want and not be wrong. The slope is irrelevant here. And I don’t really see any extreme points driving this result anyway — if you remove Johan Hedberg (90.2, 77.5 in top left) and Niklas Backstrom (91.8, 56.3 in bottom right) you get an R^2 of 0.04.
@BSH_EricT
Writer at Broad Street Hockey
When the R^2 is 0.0001, you can draw a line with any slope you want and not be wrong.
You just need to fix your axes. The tick marks on the x-axis ate 0.5% increments, and on the y-axis they are 5% increments. If it was 5% increments on both, the data would make a vertical line, so then you could say shootout sv% goes up with career sv%. Problem solved.
Lightning strikes once, Hextall strikes twice!
"I think there is virtue in pissing off idiots." - Fehr and Balanced
Fewer data points tends to increase the correlation, not decrease it, right?
Depends really. Usually having a small sample size would predispose you to rejecting the null hypothesis when the null hypothesis (that there is no correlation) is in fact true. But it doesn’t exclude the opposite from happening either. That is, it’s unlikely that fewer data points would decrease the correlation, but it’s possible. At least I think that’s right.
Simon Gagne AND Mike Richards may move between towns, wear new jerseys and call different arenas home but, at the end of the day, they will both always be Philadelphia Flyers.
One day Sean Couturier will win the Conn Smythe. You heard it here first.
by PursuitOfLappyness on Feb 10, 2012 7:52 PM EST up reply actions
Fewer data points tends to increase the correlation, not decrease it, right?
While I am no statistician, I am not aware of any statistical linkage between sample size and magnitude of a correlation. However, there is a linkage between sample size and failing to find an effect when it exists (i.e., a Type II error), as suggested by PursuitOfLappyness. In particular, the smaller sample size will result in less power, which directly raises the rate of Type II errors. Further, my personal opinion is that the larger sample is a better representation of the population of interest (in my estimation as I think it is good to include goalies such as Ward, Howard, etc. as I suggested in my original post).
When the R^2 is 0.0001, you can draw a line with any slope you want and not be wrong. The slope is irrelevant here.
I may be misunderstanding your statement, but I am not sure how you can say that the slope of a regression line is irrelevant. In particular, the slope of the regression line essentially reflects the R^2 of the relationship. So when the R^2 is zero, the slope of the regression line is also zero – That is, the slope must be flat (horizontal) with an R^2 of zero. Thus, you can’t "draw a line with any slope you want and not be wrong" – The slope of the regression line is a direct function of the R^2 (and vice versa). There is a direct connection between these statistical elements.
And I don’t really see any extreme points driving this result anyway — if you remove Johan Hedberg (90.2, 77.5 in top left) and Niklas Backstrom (91.8, 56.3 in bottom right) you get an R^2 of 0.04.
To me, your example reinforces my point – If you remove just two data points, the correlation increases quite a bit. In particular, the relationship goes from r = -.03 with 26 observations to r = .20 with 24 observations. This is quite a dramatic jump for just deleting two data points – Thus, this suggests to me that these two data points were really pulling down the regression line. While you addressed this issue by removing these two potential outliers, the approach that I took in my original post was to address it by increasing the sample size (to be more representative of the population, reduce type II errors, etc.), which also resulted in a correlation of roughly the same magnitude (r = .22)
Again, this is a small relationship (as I noted in my original post)…but, in my opinion based on these analyses, there is a connection so suggesting that there is no relationship between career save percentage and career shootout save percentage is incorrect. Just my $0.02.
But then why not include goalies with 25 shootout attempts against? More data points, increasing the sample, which is what you seem concerned about.
The R^2 there is 0.047
Why use 50, and not 25 or 100?
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by Geoff Detweiler on Feb 10, 2012 11:12 PM EST up reply actions
That’s not really fair. It’s obviously all about finding the right balance. It’s confusing because you’re working with two samples here: one is the number of shootout attempts against (you want to avoid using a small sample there) and one is the number of goalies to include in this analysis (again you want to avoid a small sample there). You avoid a small sample in the latter by risking a small sample in the former. TenZeroJig has a legitimate concern I feel.
Simon Gagne AND Mike Richards may move between towns, wear new jerseys and call different arenas home but, at the end of the day, they will both always be Philadelphia Flyers.
One day Sean Couturier will win the Conn Smythe. You heard it here first.
by PursuitOfLappyness on Feb 10, 2012 11:41 PM EST up reply actions
I am not aware of any statistical linkage between sample size and magnitude of a correlation.
It definitely exists. If you have only two data points, the correlation is unity regardless of the actual relationship between the variables. The more data you have, the lesser the contribution to R^2 from the random alignment of the points (and therefore the more confident you can be in a given magnitude correlation).
I am not sure how you can say that the slope of a regression line is irrelevant.
R^2 is a measure of how good the fit is between the line and the points. When R^2 is 0.0001, the line virtually does not fit the points at all — it may be the best fit, but it’s still terrible. The goodness of fit — the average distance between the points and the line — would scarcely be any worse at all if you rotated the line 90 degrees. There’s no reason to pay any attention to the slope of a line that fits the data that poorly.
To me, your example reinforces my point – If you remove just two data points, the correlation increases quite a bit.
Yeah, we’re just reading this one differently. I cherry-picked (with no statistical basis, a cardinal sin) the two points that would most strongly increase the correlation, and the new line still only explains 4% of the variance. With an R^2 of 0.04, we would still say that there’s basically no relationship — if that’s all we can get to by selectively removing 8% of the data to try to drive the correlation up, I don’t think we can say that a true relationship is being masked by outliers.
@BSH_EricT
Writer at Broad Street Hockey
It definitely exists. If you have only two data points, the correlation is unity regardless of the actual relationship between the variables. The more data you have, the lesser the contribution to R^2 from the random alignment of the points (and therefore the more confident you can be in a given magnitude correlation).
I have a feeling you’re on a different page on this point. Because I’m a bit confused about what the both of you are getting at.
R^2 is a measure of how good the fit is between the line and the points. When R^2 is 0.0001, the line virtually does not fit the points at all — it may be the best fit, but it’s still terrible. The goodness of fit — the average distance between the points and the line — would scarcely be any worse at all if you rotated the line 90 degrees. There’s no reason to pay any attention to the slope of a line that fits the data that poorly.
I agree with Eric on this point. In his sample, the idea is that there is no correlation. The line could’ve come up with a gradient of 15 and it wouldn’t make me any more convinced if the R^2 was still 0.0001.
Simon Gagne AND Mike Richards may move between towns, wear new jerseys and call different arenas home but, at the end of the day, they will both always be Philadelphia Flyers.
One day Sean Couturier will win the Conn Smythe. You heard it here first.
by PursuitOfLappyness on Feb 10, 2012 11:43 PM EST up reply actions
I have a feeling you’re on a different page on this point. Because I’m a bit confused about what the both of you are getting at.
I’ll back up. His suggestion was that having few data points might be the cause of the low correlation, because a few outliers might mask a true relationship. My point is that in fact it works the opposite way: with few data points, random alignment of the points tends to result in a measured correlation that is larger than the true relationship.
If you start with a billion points that have a correlation of 0.5 and select 25 of them at random, the odds are that those 25 points will have a stronger correlation than 0.5.
Again, various extremes are useful to consider:
- Instead of selecting 25 points, let’s select just two. Then the measured correlation will be 1.0 instead of the true 0.5.
- Imagine our billion-point sample had a correlation of 0.0 instead of 0.5. Then the measured correlation of the 25-point sample could (and almost certainly would) be stronger by random chance and can’t be weaker.
- However, imagine instead that our billion-point sample had a correlation of 1.0. This is the inverse of the previous scenario, and the correlation of the 25-point sample can’t be any stronger…but it also can’t be any weaker — it will be precisely 1.0 too!
So out of our universe of points, if we select the group of points that have the least noise in them and see absolutely no correlation between those points, the natural conclusion should be that there’s no relationship between the two sets of numbers, not that having so few points could be hiding a true relationship that we would bring out by including the noisier data.
@BSH_EricT
Writer at Broad Street Hockey
Having just opened this up for the first time in an actual browser, I’m a tad disappointed at the lack of funny URLs and/or photo captions.
Still a good read. I remember back after I think it was the Avalanche game where Bryz went 0/3 in the shootout and someone, in criticizing him, said that “this game’s shootout clearly shows that he doesn’t study the tendency of shooters.” Which, well, yeah.
Shootouts are just nuts. (And stupid.)
by everybodyhitswoohoo on Feb 10, 2012 3:38 PM EST reply actions
Haha, sorry. I went vanilla on the URL because I thought this might be something people would actually search for. And I chose the pic hoping for subtle emphasis of my point, but in retrospect subtlety sucks and I should’ve captioned it “HE EVEN STOPPED PAVEL FREAKING DATSYUK1”
I’ll try to do better next time.
@BSH_EricT
Writer at Broad Street Hockey
It’s all good. Out of curiosity, where did you find career shootout numbers? On nhl.com? I can only see them there by season…
by everybodyhitswoohoo on Feb 10, 2012 4:05 PM EST up reply actions
Yeah, it’s on NHL.com. One of the drop down menu options is “Active Skater – Career” or something.
Man-crushin' on Boucher since 1999 and Matt Calvert since May 2010
Broad Street Hockey - Makin' it look mean since 1967.
SB Nation Philly - Associate Editor
by Geoff Detweiler on Feb 10, 2012 4:08 PM EST up reply actions
Totally missed that. Derp. Thanks.
by everybodyhitswoohoo on Feb 10, 2012 4:13 PM EST up reply actions
The result is interesting.
I think to some extent you are oversimplifying the argument the skill side would make. Fleury is a good example since his best traits as a goalie seem to be quickness, reflexes and the like. His positioning can be bad, his stick handling is dreadful enough that it probably has a real effect and he just has these weird lapses where he lets soft goals so we’ll let’s call that mental focus. If you add it all up he ends up being decentish, but all of his positives seems important to stop a penalty shot and the negatives less so. Also, how sweet was that save on the Ovechkin breakaway in game 7?!?!?!
On the flip side, the correlation is really freaking small. Even with the type of thinking I just went through, if there were pronounced skills that varied across goalies some of that would leak through it seems like you’d at least hit double digits. The only way it would be this extreme and for there to be a big skill component would be for there to be a positive correlation between being lightning quick post to post and having a super strong desire to dick around and lose the puck behind your goal.
It’s worth pointing out that none of this shows that there is no skill, we’d be dreadful defending shootouts, it’s just that NHL level goalies are so close in those skills that they don’t matter.
Driving Play - The Blog with Three First Lines
by JaredL on Feb 10, 2012 7:44 PM EST reply actions 2 recs
Anyone out there watching college hockey. Pretty good action. Also didn’t realize that Lukko’s kid plays for Vermont.
Commenter formerly known as M from Pdaddy, but still just Call Me "M"!
DISCLAIMER: Information written above may not be entirely factual nor provable with the use of complex statistics. But it may induce thought, humor and possibly laughter.

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