Proposal: A New Way of Looking at Shots
I want to start out saying that I honestly don't know a lot about any advanced statistics in the NHL. I know more about baseball stats, but comparing baseball stats and hockey stats are like comparing cat owners to dog owners. One game has very clear start and stop points that makes it easy to gather objective data (pitcher throws ball, batter hits it to the shortstop, shortstop throws him out, next batter, MOVE ALONG TO NEXT DATA POINT, HUMAN), the other is a free-flowing and ever-changing game with fewer similarly produced setups that occur from a stoppage in play.
I also want to point out that I do like stats. That'll be apparent after you read the wall of text after the jump. I also like to take them with a grain of salt and understand that they are not actual predictors of any given situation. A shooting percentage of 20% doesn't mean that you must get the puck to that player and have him shoot 5 times per game.
Perhaps some of what I suggest already exists. Again, I know nothing about advanced hockey stats and really don't have the time to dig right now. I am going to attempt to look at the one stat I think has been getting a lot of attention lately: shots. They have become the new way to determine whether a team WINS OR LOSES THE FUTURE. Jump with me into your more immediate future to see some of my ideas in ways we could improve our understanding of the one stat I think we've seen beaten into the ground.
Next, you could add some flavors to the shot stat. Add the distance from goal to every shot. Longer shots should give the goalie more time to react. Each type of goal is often recorded in scoring, too, yes (wrister, slap shot, tip-in, etc)? Add that, but for shots. That slap shot from the blue line got re-directed into a tip in shot. They potentially have a greater chance of generating a goal since you are reducing the chance of the goalie reacting, but you are also potentially redirecting the shot wide. Another thing that is handy would be one-timers. Obviously a lot of goals are scored by a quick pass laterally across the goal to someone who one-times it past the goalie who can't react in time. Accounting for some sort of movement before a shot will help build a sense of what actually works.
From there I say you record EVERY shot, not just shots on net. How many shots end up going 3 feet wide of the net? Are deflected and go into the stands (or ideally the netting)? Slightly harder to do since it may be hard to deduce what was a shot and what was a dump behind to the boards just trying to maintain the zone. Or whatever. Stay with me, I'm going even more subjective.
From this I think you can get to the meat of what a lot of us are asking for: was the shot impeded in any way? Was there a defenseman's stick poking in at the shooter or the puck as it was shot? Was a defenseman standing in front of the shooter? Was the shooter being checked at all? The problem here is there is a lot of subjective data in what I just proposed. But hockey does have subjective stats already. What exactly is a hit? Why are some recorded and some not? (I could probably Google this, but please tell me in the comments what it is.) Is it when you knock someone off the puck, follow them into the boards, cause them to pass earlier than they wanted? Couldn't you bring that level of scrutiny to a shot? (Just how much impediment is a stick check vs a body check?)
Were there a way to get a reliable and third-party source (Nate Silver?), I think this would shed some light on how offensive and defensive systems actually work. Where are unimpeded shots coming from? Do those unimpeded shots result in goals or do they often get saved (or go three feet wide)? Where are the best places to park a defenseman? When is it best to let a shot happen and where do you absolutely want to stop a shot? Where should we be concentrating our shots on [Insert Enemy Goalie here]? This also just made me thing that you'd probably have to add another layer into each shot as well concerning whether or not the team gained the zone on a breakaway man-advantage, or if it was a play that developed through some clever forechecking, passing, and zone awareness.
Yes, I realize that teams probably already do a lot of things similar to this on their own. They probably have people pouring over tape every day seeing what other teams are doing, what's working, what's not, etc. Sadly we are not privy to team data for obvious reasons. Until our independent stat-trackers can catch up to this level and there are agreeable ways to quantify some of the subjective data, I still think we'll have people grabbing at stats that may or may not prove to be useful. Batting Average and Wins for pitchers used to be the holy grail in baseball. Now with other stats available due to an increased knowledge of the inner workings of the game and an increased use of technology and stat junkies to gather even more data from the game, their weight has been decreased.
I think shots are a good starting point because I don't believe that any two shots are the same. Nor does more shots necessarily mean more goals. I believe that is what a lot of us Wild fans are getting at. Maybe I'm completely wrong (and potentially missing a lot...I've had a lot of coffee today..). Perhaps after collecting data on everything I suggested would also suggest that the Wild are bad and OMG they are teh suck and GO FIGHTING STATS!! STATS WILL WIN THE CUP IN 16 STRAIGHT GAMES!!! If that's the case, well then, in the System I trust.
The opinions posted here are not those of Hockey Wilderness
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Should have read the Walk
Looks like FRB and I were thinking similar things.
No worries
Bryan has already said it once, but never be afraid to expand on an idea that’s in the Walk.
You know you're a Wild fan if Spam Whoopie Gerald-buns comes up in conversation
Regressing all the way back to high school hockey.
by JDesthubert on Dec 13, 2011 12:41 PM CST up reply actions
This.
Editor:Hockey Wilderness Editor:In Lax We Trust Now with more Twitterness: ReynoldsSBN
Master of unsustainable passive regression.
All of this data is available. The (x,y) coordinates of events you can get off the ESPN gamecast or NHL Gamecenter live tracker (Hawerchuk uses ESPN, I know that), and the play-by-play from NHL.com—>(go to game recap)—>stats—>Play by Play.
Anyway, this is relevant.
Red Line Station and @RedArmyLine, featuring coverage of the most frustrating team in the NHL
I believe in next year.
Thanks! Nice read there.
I guess people are taking these things into account. Interesting how apparently distance means diddly. So how about angle, type of shot, etc?
Well, there is this.
I’m pretty sure all of them incorporate shot type into some sort of “expected GF/GA” model.
In a comment here he said that factoring in whether a shot is a rebound (they show up the same on Play by Play, except they’re immediately after another shot) and x-y as opposed to pure distance hardly changes the result, at least in terms of shot quality for. I’m guessing it’s similar for GA, but not sure.
Don’t think distance means “diddly” but I think the point is more that we don’t get enough of a sample for the variance to work its way out of the data
That is, if you assign the exact same chance of scoring to each shot for every team and give each team the same amount of shots and simulate a season, you get a distribution of shooting percentage that is only slightly less wide than the observed distribution, so it’s hard to say where true talent lies.
Can’t remember off the top of my head if there’s a post specifically about defense, but I’ll be on the lookout.
Red Line Station and @RedArmyLine, featuring coverage of the most frustrating team in the NHL
I believe in next year.
by red army line on Dec 13, 2011 1:47 PM CST up reply actions
Seems like having something like what MLB does with pitch tracking would allow the shot data to be more precise. How exactly you’d do that, I don’t know. How the NHL would get something like that installed in every rink, I also don’t know.
Tracked down an article by Hawerchuk that showed how bad the recording is at Madison Square Garden. Woof.
Maybe I should drive up to Winnipeg and have a beer with him. Sounds like he’s doing interesting work.
I read that at NHL R&D camp they experimented with putting trackers in the pucks, but there were some logistical issues with that. As soon as that happens, frankly, Corsi is a dinosaur.
I wonder if you could take wide-angle video and code for a computer to track the puck.
Red Line Station and @RedArmyLine, featuring coverage of the most frustrating team in the NHL
I believe in next year.
by red army line on Dec 13, 2011 3:34 PM CST up reply actions
MLB encouranged third-party startups to devlop new tracking methods.
I’m not sure if that’s going to be economical in hockey, and Bettman probably wouldn’t do it anyway, but it’s almost certainly the right way to go.
"Shot Quality"
It’s just such a small part of a goal because of the (very general) factors it takes to get to the point where a shot is taken from (i.e. zone entry, possession, deflection(s) and more) and then what happens from when it goes in (deflection(s)/block(s), rebound(s), actual time/speed of shot).
It boils down to this: teams that take more shots (no matter what happens: blocked, missed, or on net) are generally better than teams that allow more shots and usually have a better chance of winning. While this always doesn’t work out – and even goes extended periods of time against the odds – that’s why they play the game. One truth amongst all this is that just like in all statistics; when/if the sample size becomes large enough the averages and true values always shine through.
I agree it pretty much boils down to more shots=more goals and in general that works. And that we’ll need to wait and get more data before everything averages out.
In the post that red army line linked above, the Wild are among the top teams in the last couple of years in terms of controlling shot difficulty. Whether that actually leads to being a better team and winning games is another matter, I guess.
It definitely is. Just that controlling shot quality correlates inversely with quantity (so teams that shoot a lot find it hard to get off a high proportion of good shots, while teams which are more selective with their shots have a better “typical” shot), and also the data doesn’t include this season. Hawerchuk, at least earlier, was really high on Lemaire (because he was great with matchups and his goalies were always well above average by save percentage).
Red Line Station and @RedArmyLine, featuring coverage of the most frustrating team in the NHL
I believe in next year.
by red army line on Dec 13, 2011 4:00 PM CST up reply actions
One of the most bizarre things about the Wild this year
Is how incredibly much better they have been at preventing shots when there are four guys on the ice vs. five. To me this says that there’s a definite strategic approach going on to allow more bad shots at even strength, probably because a bad shot is a good way to end a possession quickly when you have good goalies. There have certainly been a lot fewer extended opponent possessions this year than previous years.
One of the things I have real difficulty with from the Corsi supporters is the tendency to just write off special teams as unimportant. Just knocking off a third of the goals in the league can’t be a good idea.
The only view I need of Shots

I shall now leave you to your debate. ;-)
(Good post, by the way.)
Editor:Hockey Wilderness Editor:In Lax We Trust Now with more Twitterness: ReynoldsSBN
Master of unsustainable passive regression.
This
I’m now suddenly thirsty…damn subliminal messages
You know you're a Wild fan if Spam Whoopie Gerald-buns comes up in conversation
Regressing all the way back to high school hockey.
Mmmmm, Whiskey
Thank goodness there’s a game tonight now that you all got me thirsty.
by FinnfortheWin on Dec 13, 2011 3:45 PM CST up reply actions
Heh
Evan Williams is a better pricepoint for shots, in my opinion. I’m not dissing the Johnnie Blue, but if I’m spending that much I’ll go for an Ardbeg Corryvreckan. Or whatever. Ok, off to drink some whiskey.
No shots being had here, just 3 fingers on the rocks being sipped by a warm fire fueled by my new hatred for Bogodisan.
by FinnfortheWin on Dec 13, 2011 10:30 PM CST up reply actions
Let me preface by saying that dlfedie is a friend of mine
1. Love the passion
2. Like the idea of thinking in more specific terms of the type of shot. I think this idea, and consistent measurement across all NHL arenas, have merit.
3. Definitely need to measure the “identity” (for lack of a better term) of the shot. Was the goaltender screened? Is the shot deflected by a player? How many players are between the shooter & target? What type of shot: slap shot, one-timer, odd-man-rush, etc. All shots are not created equal, and as such the “identity” of a shot is more important than the fact that a shot occurred. This is the #1 thing that bothers me about Corsi, Fenwick, etc. They don’t tell the story, they simply amass the number of shots and move from there. It’s not enough with the total number of variables that exist in a hockey game.
If a better type of measurement can be posited, then I will give much more credence to this type of analysis. Until then, I simply don’t buy it. As a quantitative analyst, the concept of NHL advanced statistics bothers me to my core right now.
Proprietor of Hockey Wilderness - We take Minnesota hockey WAY too seriously.
I’ll admit my love of soccer kind of crept into writing this. There as well there’s no real good measure of worth of a player alone from goals, assists, shots, etc. It’s a similar problem to hockey where those aren’t telling the whole story. One shot on goal can actually win a game.
There are also very few ways of describing a team as a unit. Watching Barcelona and watching Man United are two different experiences. Watching Tampa and Philly are two different experiences. You can talk about 4-4-2, 4-2-3-1, and the similar sounding 2-2-1, 2-1-2 setups in hockey, but that still tells you only about the “default” mode of a team. This doesn’t tell you where they may be pressing at a certain moment, how they’re reacting to the current play, etc. You can also be vague and say they play counter attack or they like to press forward. But how your system works against other systems is an entirely different discussion.
I do like stats a lot. Baseball is generating a lot of good advanced statistics at the moment. But I agree and think people put far too much weight on advanced hockey stats right now. I feel they can’t quite actually capture and compare equally what each team or player may do in any given situation. Couple of reasons why baseball stats work so well: we have over 100 years of objective data to pour over (a double recorded in 1932 is pretty much going to be recorded the same as a double in 2011), and most importantly baseball is a more static game. Listen to a hockey game and a baseball game on the radio. One is a perfect game to listen to while driving. “Base hit to left field, that’ll put runners on the corners with no one out! Morneau up next and he is 2 for 5 lifetime against Eide..” vs. “Koivu brings the puck into the zone and dumps it around the boards where Cullen picks it up..Cullen dumps back to Spurgeon who fires a shot from the point…and Goal!!”
Stoppage in play where one thing is exactly the same at least 51 times per game weather permitting (27 outs X2 – 3 for home team winning in the top of 9th) played over many games in a year and having years and years of objective stoppages in play exactly like this is an economist’s wet dream. You can actually get good data for a given player’s (or team’s) potential performance in a certain situation (emphasis on potential…). I dare anyone tell me that they picked the Cardinals with a month left in the season.
Amorphous sports like hockey and soccer give you stats, but since you don’t have people tracking the exact position of everyone on the ice, the exact speed of the puck, the exact position of the goalie, etc, you cannot compare shots. They may have similar qualities, but these exact situations not constantly reproduced over a season.
One more thing crept into my beer soaked head while writing this. I think some people look to stats to prove or disprove an outcome. I think it gets to the heart of what sport actually is: a game. Assuming the rules are fair, anyone can actually win. Generally the stronger team wins or the current method of gauging the strongest team proves to be true. But that’s not always the case. Ask the Phillies. Depending on how much you’re invested in a game, you look for ways to prove that what should happen, will. Did I think the Packers would lose today? Nope. Was I happy when I read on the scoreline ticker that they lost to the Chiefs? Yep.

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