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overpass 08-15-2012 11:17 AM

On-ice Shooting percentage - luck or skill?
 
The answer to the question, is of course, both. But in what degree?

5 vs 5

I used behindthenet.ca's .xls files, with data from the 2007-08 season through the 2010-11 season.

EDIT: See post 22 for updated numbers - I used saved shots instead of total shots for these numbers.

Using the binomial approximation to a normal distribution, I calculated the z-score for each NHL player's on-ice shooting percentage over this time period, where z-score = (On-ice GF - On-Ice SOGF*LgSH%)/(Standard deviation calculated using binomial approximation)

Here are the players with the highest and lowest z-scores

Player Z-score 5-on-5 on-ice SH%
SIDNEYCROSBY 6.42 13.3%
HENRIKSEDIN 5.75 12.5%
DANIELSEDIN 5.22 12.3%
MARIANGABORIK 5.17 12.9%
BOBBYRYAN 5.15 12.7%
EVGENIMALKIN 5.12 12.4%
RYANGETZLAF 4.98 12.1%
ILYAKOVALCHUK 4.93 12.2%
COREYPERRY 4.59 11.8%
DANYHEATLEY 4.54 11.8%
JASONSPEZZA 4.52 12.0%
ALEXTANGUAY 4.36 12.1%
NATHANHORTON 4.29 11.8%
ALEXBURROWS 4.27 11.8%
JAROMEIGINLA 4.27 11.5%
RYANWHITNEY 4.21 12.1%
PAULSTASTNY 4.14 11.8%
MARTINST. LOUIS 4.12 11.5%
MIKERIBEIRO 4.09 11.7%
NICKLASBACKSTROM 4.07 11.4%
ALEXANDERSEMIN 3.97 11.7%
PAVELDATSYUK 3.86 11.3%
DARRYLBOYCE 3.80 17.5%
ALEXOVECHKIN 3.77 12.1%
JEFFSCHULTZ 3.76 11.4%
STEVENSTAMKOS 3.75 11.8%
NICLASHAVELID 3.53 12.4%
ALEXANDEROVECHKIN 3.48 11.7%
BRENDENMORROW 3.48 11.6%
JOETHORNTON 3.43 11.1%

Player Z-score 5-on-5 on-ice SH%
TRAVISMOEN -4.09 6.0%
SHAWNTHORNTON -3.91 5.8%
COLTONORR -3.89 4.7%
RADEKMARTINEK -3.79 6.3%
ADAMHALL -3.78 5.3%
BRENDANWITT -3.77 5.8%
DEREKMEECH -3.69 4.7%
CRAIGADAMS -3.66 5.7%
RYANHOLLWEG -3.63 2.6%
DONALDBRASHEAR -3.58 4.6%
STEPHANEVEILLEUX -3.49 6.0%
JEFFTAMBELLINI -3.45 5.9%
ANDYGREENE -3.43 6.8%
NATETHOMPSON -3.37 5.8%
RODPELLEY -3.33 4.8%
TODDMARCHANT -3.27 6.3%
SAMUELPAHLSSON -3.23 6.5%
RAITISIVANANS -3.19 4.5%
FREDRIKSJOSTROM -3.19 6.3%
TIMSTAPLETON -3.19 3.6%
DANIELWINNIK -3.12 6.7%
SCOTTGOMEZ -3.09 7.2%
ANTTIPIHLSTROM -3.06 4.0%
TOMWANDELL -3.06 5.5%
ANDREWMURRAY -3.05 5.8%
THOMASPOCK -2.90 4.3%
JAMIEMCGINN -2.90 5.7%
ANDREWPETERS -2.88 2.5%
MIKEWEAVER -2.86 7.0%
DALLASDRAKE -2.82 3.8%

Generally speaking we see skilled players outperforming the league average and "less skilled" NHL players underperforming the league average in on-ice shooting percentage.

Taking the standard deviation of the z-scores, I get 1.47. If random variation was the only factor, the standard deviation of the z-scores would be 1.00.

Following the process from this blog post:
Quote:

Step 1: Figure out how much one standard deviation is based on a binomial distribution. Vokoun faced 4249 shots, and the league average save percentage was .920, so one SD is sqrt (.92*.08/4249) = .0042.

Step 2: Figure out how much away you are from the mean. Vokoun’s save percentage was .931, and so was +.0108 from the mean.

Step 3: Figure out how many SD that is. .0108/.0042 = 2.59. That’s his z-score.

Step 4: Do it for all the goalies. (Thomas is 2.57, Luongo is 2.53… Holmqvist is -3.11, Raycroft is -2.34).

Step 5: Find the standard deviation of all the z-scores. In this case, for these 55 goalies, it’s 1.38.

Step 6: Rejoice if the number is substantially higher than 1.00. Happiness sets in at 1.10. You did good at 1.20. If you get 1.40, you’ve definitely found something.

Step 7: Figure out the average number of opportunities for each player. In this case, the average shots faced was 2665.

Step 8: Do this: 1 - 1/1.38^2 = 0.47. That’s your r or r-squared. (Longer story later. Just call it r for now.) That 1.38 was from Step 6.

Step 9: Do this: (1-r)/r * 2665. We get 2969. The 2665 is from Step 7.

That’s the key number. 2969. Let’s call it 3000. That’s how much you use to regress a goalie’s performance. You add 3000 shots of league average performance. So Vokoun’s 4249 shots at .931 save percentage gets added to 3000 shots at .920 save percentage for a best-estimate true talent level of .926. Holmqvist’s .900 with 1809 shots becomes .912. So, the observed difference between the two goalies (.031 saves per shot) becomes a true difference of .014.
Step 7: 768
Step 8: 0.54
Step 9: 657

So, given a player's on-ice shooting percentage from 2007-08 to 2010-11, the best predictor of his 2011-12 on-ice shooting percentage is his 2007-08 through 2010-11 shooting percentage plus 657 shots at a league average shooting percentage. Because Sidney Crosby was on the ice for 1867 shots at a 13.3 SH%, his predicted 2011-12% would be 12.2%.

Best and worst predicted 2011-12 5 vs 5 on-ice shooting percentages

Player Predicted 5vs5 on-ice SH%
SIDNEYCROSBY 12.2%
HENRIKSEDIN 11.7%
MARIANGABORIK 11.7%
BOBBYRYAN 11.6%
EVGENIMALKIN 11.5%
DANIELSEDIN 11.5%
ILYAKOVALCHUK 11.4%
RYANGETZLAF 11.4%
JASONSPEZZA 11.2%
ALEXTANGUAY 11.2%

Player Predicted 5vs5 on-ice SH%
COLTONORR 6.8%
TRAVISMOEN 6.9%
ADAMHALL 6.9%
SHAWNTHORNTON 6.9%
DEREKMEECH 7.0%
BRENDANWITT 7.0%
CRAIGADAMS 7.0%
DONALDBRASHEAR 7.0%
RADEKMARTINEK 7.1%
STEPHANEVEILLEUX 7.1%

I'll see if I can get the 2011-12 data to test the predictions.

wgknestrick 08-15-2012 11:23 AM

Quote:

Originally Posted by overpass (Post 53594165)
The answer to the question, is of course, both. But in what degree?

5 vs 5

I used behindthenet.ca's .xls files, with data from the 2007-08 season through the 2010-11 season.

Using the binomial approximation to a normal distribution, I calculated the z-score for each NHL player's on-ce

There is certainly some skill involved and most of that skill comes from getting yourself and the puck as close to the net as possible.

Czech Your Math 08-15-2012 12:02 PM

It's all luck... Pretty Darn Obvious

CanadianHockey 08-15-2012 12:27 PM

There are certainly examples of players having high shooting percentages but not being particularly skilled shooters.

Milan Lucic is a perfect example. One of four players to appear in the top-20 S% leaders (using NHL.com as reference) in both 10/11 and 11/12. That's not indicative of his shooting skills - rather, it's indicative of his style of play. He crashes the crease, and as a result is in a position where he rarely takes shots, but when he does it's in close and often with the goaltender out of position (be it due to a loose puck in the crease, a rebound, or a cross crease pass).

On the whole I'd say higher shooting percentages are generally indicative of better shooters, though. Your data seems to indicate just as much.

TheDevilMadeMe 08-15-2012 02:24 PM

This is a really simple example, but look at the list of the highest shooting percentages in NHL history:

http://www.hockey-reference.com/lead...ct_season.html

The list is littered with players who played on the same line as all-time great playmakers. Mario Lemieux's famous leaches (Rob Brown and Warren Young) are right near the top. Charlie Simmer was Marcel Dionne's triggerman.

Sergei Makarov, who was trained in the Soviet system which favored precision passing and shot quality over quantity, is also prominent on the list.

Mystlyfe 08-15-2012 02:36 PM

Many of the commentors seem to either have not read the OP or misunderstand what on-ice shooting% is. On-ice shooting% is not the same as shooting%. On-ice shooting% is his teams' shooting% while he is on the ice, not just the players'.

So if my team takes 10 shots in a game and scored on 2 of them, my on-ice shooting% for that game is 20%, regardless of how many of those shots or goals were scored by me.



Semi-related to the above, LOL @ Jeff Schultz being carried towards the top of that list.

Dr Quincy 08-15-2012 02:58 PM

Quote:

Originally Posted by Mystlyfe (Post 53600777)
Many of the commentors seem to either have not read the OP or misunderstand what on-ice shooting% is. On-ice shooting% is not the same as shooting%. On-ice shooting% is his teams' shooting% while he is on the ice, not just the players'.

So if my team takes 10 shots in a game and scored on 2 of them, my on-ice shooting% for that game is 20%, regardless of how many of those shots or goals were scored by me.



Semi-related to the above, LOL @ Jeff Schultz being carried towards the top of that list.

Exactly and the theory would be that Crosby's on ice shooting pct is so high because of his playmaking abilities. His ability means easier goals for other guys on the ice with him.

wgknestrick 08-15-2012 03:08 PM

Quote:

Originally Posted by Dr Quincy (Post 53601523)
Exactly and the theory would be that Crosby's on ice shooting pct is so high because of his playmaking abilities. His ability means easier goals for other guys on the ice with him.

The skill is getting the puck close to the net. Good players can do this and their teammates also benefit from it. Also remember that this list is almost entirely forwards and the top guys are individually 1/3rd (or maybe more) of the contribution to their "team" SH%.

TheDevilMadeMe 08-15-2012 03:59 PM

Quote:

Originally Posted by Mystlyfe (Post 53600777)
Many of the commentors seem to either have not read the OP or misunderstand what on-ice shooting% is. On-ice shooting% is not the same as shooting%. On-ice shooting% is his teams' shooting% while he is on the ice, not just the players'.

So if my team takes 10 shots in a game and scored on 2 of them, my on-ice shooting% for that game is 20%, regardless of how many of those shots or goals were scored by me.



Semi-related to the above, LOL @ Jeff Schultz being carried towards the top of that list.

I didnt see anyone in this thread who misunderstood that. The point of my post was to show how guys like Gretzky, Lemieux, and Dionne drive up the shootin percentages of players they play with.

And yeah, Shultz definitely "got lucky" by sharing a lot of ice time with Mike Green and Alex Ovechkin

Talks to Goalposts 08-15-2012 04:24 PM

The biggest factor in most cases is going to be the the player's own personal shooting percentage, which is definitely skill based.

Remember that the 3 forwards take the bulk of the shots at even strength, and that a star forward is going to take a disproportionate number of his line's shots. So their personal rate is going to affect much more than 1/5th of the total shots.

Tanguay, Kovalchuk, Horton, Gaborik, Stamkos and Crosby being examples

Then your going to have linemate factors. The guys that are usually at the tops of these lists are also those that have consistantly been on lines with good players/good shooters, which is why they tend to come in pairs and trios.

e.g. Sedin-Sedin-Burrows, Riberio-Morrow, Getzalf-Perry-Ryan, Backstrom-Ovechkin-Semin, Stamkos-St. Louis.

After that we have actual ability to drive team-mates shooting, which seems to exist but is relatively small and not very prevalent. Crosby would definately be an example though.

Mystlyfe 08-15-2012 10:35 PM

Quote:

Originally Posted by Talks to Goalposts (Post 53604085)
Then your going to have linemate factors. The guys that are usually at the tops of these lists are also those that have consistantly been on lines with good players/good shooters, which is why they tend to come in pairs and trios.

e.g. Sedin-Sedin-Burrows, Riberio-Morrow, Getzalf-Perry-Ryan, Backstrom-Ovechkin-Semin, Stamkos-St. Louis.

Ovechkin and Backstrom have spent a majority of their time together during the span of this data, but Semin was typically found on a different line. He typically topped out at around 20% of his even strength time with Ovie and Backstrom, while the rest of it was spent with an assortment of players (Laich, Johansson, Arnott, Belanger, Morrison, Chimera, Sturm, Fleischmann, etc).

They were typically united on the powerplay, but these stats are only 5-on-5.

TheDevilMadeMe 08-15-2012 10:57 PM

Quote:

Originally Posted by wgknestrick (Post 53601857)
The skill is getting the puck close to the net. Good players can do this and their teammates also benefit from it. Also remember that this list is almost entirely forwards and the top guys are individually 1/3rd (or maybe more) of the contribution to their "team" SH%.

I'm sure there's a reason you're so adamant that the stars who drive up on-ice shooting percentage do so by getting the puck close to the net, rather than by playmaking, but I don't know what it is.

Talks to Goalposts 08-15-2012 11:33 PM

Quote:

Originally Posted by Mystlyfe (Post 53614779)
Ovechkin and Backstrom have spent a majority of their time together during the span of this data, but Semin was typically found on a different line. He typically topped out at around 20% of his even strength time with Ovie and Backstrom, while the rest of it was spent with an assortment of players (Laich, Johansson, Arnott, Belanger, Morrison, Chimera, Sturm, Fleischmann, etc).

They were typically united on the powerplay, but these stats are only 5-on-5.

I forgot about that. Semin would be more like Kovalchuk/Gaborik then.

I'm also pretty sure there's an error in how the OP found the team on ice shooting percentage of the top guys. I looked at top on-ice shootings from 2007-2011 found this.

Gaborik: 11.31
Crosby: 10.91
Ryan: 10.84
Tanguay: 10.82
H Sedin: 10.50
S Sedin: 10.40
Downie: 10.39
Dumont: 10.37
Malkin: 10.30
Horton: 10.23

SmellOfVictory 08-15-2012 11:34 PM

Further evidence that Crosby is ridiculously good. Love the work, by the way.

SmellOfVictory 08-15-2012 11:38 PM

Quote:

Originally Posted by TheDevilMadeMe (Post 53615327)
I'm sure there's a reason you're so adamant that the stars who drive up on-ice shooting percentage do so by getting the puck close to the net, rather than by playmaking, but I don't know what it is.

I'd argue that playmaking is a facet of getting the puck close to the net. When is playmaking most effective? When the recipient is in the slot or close in, just outside the slot. Although 'getting the puck close/open' might be slightly more accurate, since there are times when the shooter is relatively far out and the playmaker simply gives him an open net to shoot at.

I agree with the other poster that it would be more accurate to say that Crosby's skill is getting the puck close to the net, because although he's a fantstic playmaker, he's also just really good at taking it there himself and scoring (hence his high personal shooting percentage).



@TalksToGoalposts: Just wanted to mention that Tanguay is a bad example of "high SH% player taking lion's share of shots", since he averages around 100 shots/season. His personal shot percentage is ludicrously high, though, and he does play on a line with Iginla.

Talks to Goalposts 08-16-2012 12:34 AM

Quote:

Originally Posted by SmellOfVictory (Post 53616263)
I'd argue that playmaking is a facet of getting the puck close to the net. When is playmaking most effective? When the recipient is in the slot or close in, just outside the slot. Although 'getting the puck close/open' might be slightly more accurate, since there are times when the shooter is relatively far out and the playmaker simply gives him an open net to shoot at.

I agree with the other poster that it would be more accurate to say that Crosby's skill is getting the puck close to the net, because although he's a fantstic playmaker, he's also just really good at taking it there himself and scoring (hence his high personal shooting percentage).



@TalksToGoalposts: Just wanted to mention that Tanguay is a bad example of "high SH% player taking lion's share of shots", since he averages around 100 shots/season. His personal shot percentage is ludicrously high, though, and he does play on a line with Iginla.

Any even strength forward that takes a reasonable portion of their lines shots can have an effect. In this case Tanguay shots at near 20% on 5 on 5 while a typical forward gets about 9%. But as a forward who isn't getting a ton of shots Tanguay would be getting around 1/4th of his team's shots 5 on 5 (defensemen shot rate is about half a forwards). 1/4th boost to twice the typical rate results in about 20% higher team on ice rate for Tanguay. If we use average shooting as 8% and multiply by 1.2 we get 9.6 which is in the ballpark of what Tanguay's on ice is like.

This only works for such a low shot rate because Tanguay's personal shooting% is so through the roof.

These aren't the exact numbers for Tanguay but are in the ball park to show the general idea. That he's often played with another high % shooter in Iginla as well would also be a factor but only for two of the 2007-11 seasons.

Ohashi_Jouzu 08-16-2012 07:54 AM

Quote:

Originally Posted by TheDevilMadeMe (Post 53603349)
I didnt see anyone in this thread who misunderstood that. The point of my post was to show how guys like Gretzky, Lemieux, and Dionne drive up the shootin percentages of players they play with.

And yeah, Shultz definitely "got lucky" by sharing a lot of ice time with Mike Green and Alex Ovechkin

Of course, that's not just about their ability to get pucks to the net for their teammates to bury; they drive up the on-ice S% through the chances they buried themselves, also (obviously). Somewhere along the line someone has to get some credit for getting them the puck in those situations, too.

So year-to-year trends are going to show how "luck" has affected them (through linemates, matchups, team, role, whatever), but if you look at multiple year stretches, players who appear near the top should be considered "skilled" - even if they are "leaching" off of "top" players over that period. Schultz though...

Fourier 08-16-2012 08:03 AM

Quote:

Originally Posted by TheDevilMadeMe (Post 53600397)
This is a really simple example, but look at the list of the highest shooting percentages in NHL history:

http://www.hockey-reference.com/lead...ct_season.html

The list is littered with players who played on the same line as all-time great playmakers. Mario Lemieux's famous leaches (Rob Brown and Warren Young) are right near the top. Charlie Simmer was Marcel Dionne's triggerman.

Sergei Makarov, who was trained in the Soviet system which favored precision passing and shot quality over quantity, is also prominent on the list.

Conjecture: Playing with great playmakers helps your shooting %. :)

overpass 08-16-2012 11:03 AM

Quote:

Originally Posted by Talks to Goalposts (Post 53616145)
I forgot about that. Semin would be more like Kovalchuk/Gaborik then.

I'm also pretty sure there's an error in how the OP found the team on ice shooting percentage of the top guys. I looked at top on-ice shootings from 2007-2011 found this.

Gaborik: 11.31
Crosby: 10.91
Ryan: 10.84
Tanguay: 10.82
H Sedin: 10.50
S Sedin: 10.40
Downie: 10.39
Dumont: 10.37
Malkin: 10.30
Horton: 10.23

I'll look at the numbers again. I may very well have misunderstood something in the excel file.

Pog Form 08-16-2012 11:52 AM

I just finished taking a Sociology statistics class (Quantitative Analysis) and wish my z-scores had been this interesting. :(

overpass 08-16-2012 12:25 PM

It appears that I misread the "saved shots" column as "total shots". I'll rerun the numbers.

overpass 08-16-2012 12:31 PM

5 vs 5

I used behindthenet.ca's .xls files, with data from the 2007-08 season through the 2010-11 season.

Using the binomial approximation to a normal distribution, I calculated the z-score for each NHL player's on-ice shooting percentage over this time period, where z-score = (On-ice GF - On-Ice SOGF*LgSH%)/(Standard deviation calculated using binomial approximation)

Here are the players with the highest and lowest z-scores

Player Z-score 5-on-5 on-ice SH%
SIDNEYCROSBY 6.12 11.7%
HENRIKSEDIN 5.49 11.1%
DANIELSEDIN 4.98 10.9%
MARIANGABORIK 4.93 11.4%
BOBBYRYAN 4.91 11.3%
EVGENIMALKIN 4.88 11.0%
RYANGETZLAF 4.75 10.8%
ILYAKOVALCHUK 4.70 10.8%
COREYPERRY 4.37 10.6%
DANYHEATLEY 4.33 10.5%
JASONSPEZZA 4.31 10.7%
ALEXTANGUAY 4.15 10.8%
NATHANHORTON 4.10 10.5%
ALEXBURROWS 4.08 10.6%
JAROMEIGINLA 4.07 10.3%
RYANWHITNEY 4.02 10.8%
PAULSTASTNY 3.95 10.6%
MARTINST. LOUIS 3.93 10.3%
MIKERIBEIRO 3.90 10.5%
NICKLASBACKSTROM 3.88 10.2%
ALEXANDERSEMIN 3.78 10.5%
PAVELDATSYUK 3.68 10.2%
DARRYLBOYCE 3.62 14.9%
ALEXOVECHKIN 3.59 10.8%
JEFFSCHULTZ 3.59 10.3%
STEVENSTAMKOS 3.58 10.6%
NICLASHAVELID 3.37 11.0%
ALEXANDEROVECHKIN 3.32 10.5%
BRENDENMORROW 3.32 10.4%
JOETHORNTON 3.27 10.0%

Player Z-score 5-on-5 on-ice SH%
TRAVISMOEN -3.90 5.6%
SHAWNTHORNTON -3.73 5.5%
COLTONORR -3.71 4.5%
RADEKMARTINEK -3.62 5.9%
ADAMHALL -3.60 5.0%
BRENDANWITT -3.59 5.5%
DEREKMEECH -3.52 4.5%
CRAIGADAMS -3.49 5.4%
RYANHOLLWEG -3.46 2.6%
DONALDBRASHEAR -3.42 4.4%
STEPHANEVEILLEUX -3.33 5.6%
JEFFTAMBELLINI -3.29 5.6%
ANDYGREENE -3.27 6.4%
NATETHOMPSON -3.22 5.5%
RODPELLEY -3.18 4.6%
TODDMARCHANT -3.12 5.9%
SAMUELPAHLSSON -3.08 6.1%
RAITISIVANANS -3.05 4.3%
FREDRIKSJOSTROM -3.04 5.9%
TIMSTAPLETON -3.04 3.4%
DANIELWINNIK -2.97 6.3%
SCOTTGOMEZ -2.95 6.8%
ANTTIPIHLSTROM -2.92 3.8%
TOMWANDELL -2.92 5.2%
ANDREWMURRAY -2.91 5.5%
THOMASPOCK -2.77 4.1%
JAMIEMCGINN -2.76 5.4%
ANDREWPETERS -2.75 2.4%
MIKEWEAVER -2.73 6.6%
DALLASDRAKE -2.69 3.6%

Generally speaking we see skilled players outperforming the league average and "less skilled" NHL players underperforming the league average in on-ice shooting percentage.

Taking the standard deviation of the z-scores, I get 1.41. If random variation was the only factor, the standard deviation of the z-scores would be 1.00.

Following the process from this blog post:


Step 7: 838
Step 8: 0.49
Step 9: 860

So, given a player's on-ice shooting percentage from 2007-08 to 2010-11, the best predictor of his 2011-12 on-ice shooting percentage is his 2007-08 through 2010-11 shooting percentage plus 860 shots at a league average shooting percentage. Because Sidney Crosby was on the ice for 1867 shots at a 11.7 SH%, his predicted 2011-12% would be 10.7%.

Best and worst predicted 2011-12 5 vs 5 on-ice shooting percentages

Player Predicted 5vs5 on-ice SH%
SIDNEYCROSBY 10.7%
HENRIKSEDIN 10.4%
MARIANGABORIK 10.3%
BOBBYRYAN 10.3%
EVGENIMALKIN 10.2%
DANIELSEDIN 10.2%
RYANGETZLAF 10.1%
ILYAKOVALCHUK 10.1%
JASONSPEZZA 10.0%
ALEXTANGUAY 10.0%

Player Predicted 5vs5 on-ice SH%
TRAVISMOEN 6.6%
COLTONORR 6.6%
SHAWNTHORNTON 6.6%
ADAMHALL 6.6%
BRENDANWITT 6.7%
DEREKMEECH 6.7%
CRAIGADAMS 6.7%
RADEKMARTINEK 6.7%
DONALDBRASHEAR 6.7%
STEPHANEVEILLEUX 6.8%

Master_Of_Districts 08-16-2012 07:10 PM

Quote:

Originally Posted by overpass (Post 53626249)
5 vs 5

I used behindthenet.ca's .xls files, with data from the 2007-08 season through the 2010-11 season.

Using the binomial approximation to a normal distribution, I calculated the z-score for each NHL player's on-ice shooting percentage over this time period, where z-score = (On-ice GF - On-Ice SOGF*LgSH%)/(Standard deviation calculated using binomial approximation)

Here are the players with the highest and lowest z-scores

Player Z-score 5-on-5 on-ice SH%
SIDNEYCROSBY 6.12 11.7%
HENRIKSEDIN 5.49 11.1%
DANIELSEDIN 4.98 10.9%
MARIANGABORIK 4.93 11.4%
BOBBYRYAN 4.91 11.3%
EVGENIMALKIN 4.88 11.0%
RYANGETZLAF 4.75 10.8%
ILYAKOVALCHUK 4.70 10.8%
COREYPERRY 4.37 10.6%
DANYHEATLEY 4.33 10.5%
JASONSPEZZA 4.31 10.7%
ALEXTANGUAY 4.15 10.8%
NATHANHORTON 4.10 10.5%
ALEXBURROWS 4.08 10.6%
JAROMEIGINLA 4.07 10.3%
RYANWHITNEY 4.02 10.8%
PAULSTASTNY 3.95 10.6%
MARTINST. LOUIS 3.93 10.3%
MIKERIBEIRO 3.90 10.5%
NICKLASBACKSTROM 3.88 10.2%
ALEXANDERSEMIN 3.78 10.5%
PAVELDATSYUK 3.68 10.2%
DARRYLBOYCE 3.62 14.9%
ALEXOVECHKIN 3.59 10.8%
JEFFSCHULTZ 3.59 10.3%
STEVENSTAMKOS 3.58 10.6%
NICLASHAVELID 3.37 11.0%
ALEXANDEROVECHKIN 3.32 10.5%
BRENDENMORROW 3.32 10.4%
JOETHORNTON 3.27 10.0%

Player Z-score 5-on-5 on-ice SH%
TRAVISMOEN -3.90 5.6%
SHAWNTHORNTON -3.73 5.5%
COLTONORR -3.71 4.5%
RADEKMARTINEK -3.62 5.9%
ADAMHALL -3.60 5.0%
BRENDANWITT -3.59 5.5%
DEREKMEECH -3.52 4.5%
CRAIGADAMS -3.49 5.4%
RYANHOLLWEG -3.46 2.6%
DONALDBRASHEAR -3.42 4.4%
STEPHANEVEILLEUX -3.33 5.6%
JEFFTAMBELLINI -3.29 5.6%
ANDYGREENE -3.27 6.4%
NATETHOMPSON -3.22 5.5%
RODPELLEY -3.18 4.6%
TODDMARCHANT -3.12 5.9%
SAMUELPAHLSSON -3.08 6.1%
RAITISIVANANS -3.05 4.3%
FREDRIKSJOSTROM -3.04 5.9%
TIMSTAPLETON -3.04 3.4%
DANIELWINNIK -2.97 6.3%
SCOTTGOMEZ -2.95 6.8%
ANTTIPIHLSTROM -2.92 3.8%
TOMWANDELL -2.92 5.2%
ANDREWMURRAY -2.91 5.5%
THOMASPOCK -2.77 4.1%
JAMIEMCGINN -2.76 5.4%
ANDREWPETERS -2.75 2.4%
MIKEWEAVER -2.73 6.6%
DALLASDRAKE -2.69 3.6%

Generally speaking we see skilled players outperforming the league average and "less skilled" NHL players underperforming the league average in on-ice shooting percentage.

Taking the standard deviation of the z-scores, I get 1.41. If random variation was the only factor, the standard deviation of the z-scores would be 1.00.

Following the process from this blog post:


Step 7: 838
Step 8: 0.49
Step 9: 860

So, given a player's on-ice shooting percentage from 2007-08 to 2010-11, the best predictor of his 2011-12 on-ice shooting percentage is his 2007-08 through 2010-11 shooting percentage plus 860 shots at a league average shooting percentage. Because Sidney Crosby was on the ice for 1867 shots at a 11.7 SH%, his predicted 2011-12% would be 10.7%.

Best and worst predicted 2011-12 5 vs 5 on-ice shooting percentages

Player Predicted 5vs5 on-ice SH%
SIDNEYCROSBY 10.7%
HENRIKSEDIN 10.4%
MARIANGABORIK 10.3%
BOBBYRYAN 10.3%
EVGENIMALKIN 10.2%
DANIELSEDIN 10.2%
RYANGETZLAF 10.1%
ILYAKOVALCHUK 10.1%
JASONSPEZZA 10.0%
ALEXTANGUAY 10.0%

Player Predicted 5vs5 on-ice SH%
TRAVISMOEN 6.6%
COLTONORR 6.6%
SHAWNTHORNTON 6.6%
ADAMHALL 6.6%
BRENDANWITT 6.7%
DEREKMEECH 6.7%
CRAIGADAMS 6.7%
RADEKMARTINEK 6.7%
DONALDBRASHEAR 6.7%
STEPHANEVEILLEUX 6.8%

Nice work.

I can't remember if the data at behindthenet includes empty net goals.


I know the data is ostensibly 5 v 5 only, but 6 v 5 situations may have been included.

What is the aggregate on-ice shooting percentage in your sample?

If it's not almost exactly 0.08, then empty net goals haven't been removed.

overpass 08-16-2012 07:52 PM

Quote:

Originally Posted by Master_Of_Districts (Post 53638151)
Nice work.

I can't remember if the data at behindthenet includes empty net goals.


I know the data is ostensibly 5 v 5 only, but 6 v 5 situations may have been included.

What is the aggregate on-ice shooting percentage in your sample?

If it's not almost exactly 0.08, then empty net goals haven't been removed.

The aggregate on-ice shooting percentage in the sample is 8.28%.

Master_Of_Districts 08-16-2012 08:31 PM

Quote:

Originally Posted by overpass (Post 53639119)
The aggregate on-ice shooting percentage in the sample is 8.28%.

Thanks.

Yeah, empty net goals definitely weren't removed in that case.


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