Correlation between shot quality and number of shots?

[BrettNYR]

Intuitively, I've thought shot quality and number of shots would have some degree of correlation, but I've recently read that is not the case. For example, I thought teams with high Corsi's would be more likely to have lower PDO's/S%. Teams tend to fire shots at the net when down a goal, for example, instead of trying to set up a higher quality chance.

Does anyone have a link to a study or blog that discusses this?

Thank you.

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[shane1342o]

Intuitively, I've thought shot quality and number of shots would have some degree of correlation, but I've recently read that is not the case. For example, I thought teams with high Corsi's would be more likely to have lower PDO's/S%. Teams tend to fire shots at the net when down a goal, for example, instead of trying to set up a higher quality chance.

Does anyone have a link to a study or blog that discusses this?

Thank you.

http://hockeyanalysis.com/2015/01/17/possession-shooting-percentage-outlier-teams/

The only problem with this is that the writer removes a large portion of the data set (outliers) in order to reach the conclusion, but I still think its got some good points.

 

[BrettNYR]

Thanks, Shane!

 

[eklunds source]

Shot Quality Matters, but how much?

I don't think anyone believes that there is no such thing as shot quality, that all shots are equal. The argument is actually that most shot quality effects are smaller than people think, and that over the sample sizes we normally work with, differences in shot quality tend to be dominated more by noise than talent.

Shot Quality Revisited: A look at at the correlation between scoring chances and shot totals

Whatever tendency certain players might have for driving their team to get more scoring chances than a simple shot differential predicts is small and swamped by random noise. This suggests tracking scoring chances isn't adding much information to the readily available shot differential numbers.

Exploring the theoretical limits of shot quality

Expected shooting% is a repeatable statistic at the season level, and it has more predictive power then raw shooting% season to season.

That last one is pretty interesting -- if you know how a players' shots break down (snap, wrist, slap, backhand, tip), how much time he's spends playing while trailing/winning, how far from the net his average shot location is, etc, you can more accurately predict his shooting percentage than using his empirical results.

 

[Micklebot]

Shot Quality Matters, but how much?


Shot Quality Revisited: A look at at the correlation between scoring chances and shot totals


Exploring the theoretical limits of shot quality

That last one is pretty interesting -- if you know how a players' shots break down (snap, wrist, slap, backhand, tip), how much time he's spends playing while trailing/winning, how far from the net his average shot location is, etc, you can more accurately predict his shooting percentage than using his empirical results.

Weird to see that backhands have the highest sh% of any shot other than tip ins and deflections. the only logical reason I can think of is you are far less likely to take a backhand unless you have a gaping open net or something.

Also interesting that shots immediately following a faceoff are less likely to score; perhaps they are more likely to be slap shots (lowest sh% type of shot) and less likely to have a moving goalie?

 

[Ohashi_Jouzu*]

Weird to see that backhands have the highest sh% of any shot other than tip ins and deflections. the only logical reason I can think of is you are far less likely to take a backhand unless you have a gaping open net or something.

Backhands are also most common in wrap-around type scenarios, and dekes to get around goalies, opening up more net.

Also interesting that shots immediately following a faceoff are less likely to score; perhaps they are more likely to be slap shots (lowest sh% type of shot) and less likely to have a moving goalie?

Also more likely to have a high number/concentration of bodies in the way, I'd say.

 

[Feed Me A Stray Cat]

Weird to see that backhands have the highest sh% of any shot other than tip ins and deflections. the only logical reason I can think of is you are far less likely to take a backhand unless you have a gaping open net or something.

Also interesting that shots immediately following a faceoff are less likely to score; perhaps they are more likely to be slap shots (lowest sh% type of shot) and less likely to have a moving goalie?

Backhands are almost always in close proximity to the net. Slapshots are far out, and so are many wristers.

 

[Mickey Marner]

Weird to see that backhands have the highest sh% of any shot other than tip ins and deflections. the only logical reason I can think of is you are far less likely to take a backhand unless you have a gaping open net or something.

Also interesting that shots immediately following a faceoff are less likely to score; perhaps they are more likely to be slap shots (lowest sh% type of shot) and less likely to have a moving goalie?

In addition to what others have said, goalies also have a harder time reading/predicting the trajectory of backhand shots than they do forehand shots.

 

[oilerbear]

Intuitively, I've thought shot quality and number of shots would have some degree of correlation, but I've recently read that is not the case. For example, I thought teams with high Corsi's would be more likely to have lower PDO's/S%. Teams tend to fire shots at the net when down a goal, for example, instead of trying to set up a higher quality chance.

Does anyone have a link to a study or blog that discusses this?

Thank you.

Shot quality RE: goalie Elevation.

I find a puck directed at the net (corsi)
does not go in if it is
1. blocked
2. misses the net
3. shots that hits a stationary goalie:
-in the glove
-in the blocker
-in the Pads
-in the chest
-in the pants
4. the shots at the open areas of elevation that are actually saved.

The shots at open areas of Elevation not saved are goals.

Quality shots are the ones that require goalie movement to open area of net elevation to stop!

 

[Micklebot]

Backhands are also most common in wrap-around type scenarios, and dekes to get around goalies, opening up more net.

Yep, while I didn't elaborate on why there would be an open net, those are pretty much what I had in mind.

Also more likely to have a high number/concentration of bodies in the way, I'd say.

Agreed.

Backhands are almost always in close proximity to the net. Slapshots are far out, and so are many wristers.

Good point, it would be interesting to break up shot types into groups of similar distances. I don't thing it's fair to compare a wrister from the point that was made in hope of getting a tip to a backhander from 5 feet out.

In addition to what others have said, goalies also have a harder time reading/predicting the trajectory of backhand shots than they do forehand shots.

Sure, but given the choice, the shooter would likely prefer to take a wrister or a snap shot I think. I guess what it comes down to is shots after a deke are likely much more successful, and backhands are likely most common after a deke.