Gabe Desjardins of Arctic Ice Hockey asks the question about whether a player can influence his teammates shooting percentage. To answer this question he took a look at the Pittsburgh Penguins shooting percentages with and without Mario Lemieux. The conclusion:
I’d posit that Lemieux’s playmaking contribution is about as large as we’re going to consistently find – something on the order of 7-8% – and we can use it to bound the impact that a player can truly have on the quality of his teammates’ scoring chances.
Since I have the numbers handy I figured I’d take a look at some more recent examples but instead of looking at straight shooting percentage I looked at corsi shooting percentage (since I had corsi data more available). Corsi shooting percentage is simply goals for divided by corsi for. I’d consider Joe Thornton one of the premiere playmaking centers in the league today so let’s take a look at how some players performed while playing with, and without, him.
|CSH% With Thornton||CSH% Without||Boost|
I included the past 4 years with Marleau, 3 years with Setogutchi and 2 years with Heatley. That would indicate Thornton has an approximately 30% boost in corsi shooting percentage to his teammates. Certainly far more than the 8% Gabe predicted as the upper bound.
Now, let’s take a look at another great player, Sidney Crosby.
|CSH% With||CSH% Without||Boost|
All players are using 4 years of data. I included Fleury in the list because it provides a good proxy of the Penguins shooting percentages when Crosby is on the ice vs when he is not. This would seem to indicate that Crosby is worth a nearly 40% boost in his teams shooting percentage. That’s significantly more than even Thornton and a massive amount more than Gabe’s estimated upper bound. Maybe we should revise the upper bound to be 40%, not 8%.
For interest sake, here how much Crosby influenced his teammates corsi rates.
|Boost in CF20|
While a ~20% boost is significant, it is at best only half the boost he provided to corsi shooting percentage. Driving shooting percentage is a more significant reason why Crosby is so good offensively than driving corsi events.
Update: Eric over at Broad St. Hockey has an interesting post looking at individual shooting percentages as opposed to on-ice shooting percentages as I did above. Four of the players he looked at are H. Sedin, Crosby, Thornton and Datsyuk and for each he looked at a number of teammates with at least 30 shots with and without. Taking it a step further I think it is necessary to average across players to get a better idea of what is happening. If you do that, this is what you get:
Wow, that might make Sedin the best playmaker in the league, by a significant margin. Crosby doesn’t look quite as good as my “on-ice” analysis but that is because much of the reason why Crosby improves his linemates on-ice shooting percentage is because he is such a great shooter himself.
The point still stands, without considering shooting percentages we aren’t getting anywhere close to having a complete analysis of a players impact on the game.