April 2, 2012 Leave a comment
The game of hockey is a fast paced flow sport that demands many different actions and reactions for each player. These events can be seen and understood in many different ways and how success or failure is measured can, at times, be subjective. One of the more cut and dry areas of hockey analytics and statistics is scoring chances. Every team that plays at a high level looks at the impact of scoring chances on a game. It is safe to assume that most teams always attempt to out-chance the opponent.
What is a scoring chance? There is no universal definition, but it is a stat that is universally tracked. At UMass, we define a scoring chance as a shot from Grade-A (the area in between the faceoff dots, from the top of the circles down to the goal line) that hits the net. While this eliminates shots that hit the post and pucks that roll untouched through the crease (among others), it is the most objective way to look at scoring chances. We also look at scoring opportunities which include plays that would have been a chance if the puck was on net.
Why are scoring chances important? In hockey, the object is to score more goals than the opponent. While there are always outliers, it is safe to say that teams score more goals from the scoring area pictured than from the perimeter of the ice sheet. As a coach, I want to know how many scoring chances my team generated and how many we surrendered. I also want to know what our shooting percentage is on scoring chances and what our goalies’ save percentage is on scoring chances against. These are numbers that I can use to quantify our performance in the most important area of the ice, both offensively and defensively.
Scoring chances and scoring chance involvement can be tracked on an individual level as well. While this begins to enter the more subjective range, it is a way to see how a player is getting involved both offensively and defensively. Defensemen will often be skewed towards the negative, while Forwards will skew towards the positive, as this is the nature of their position. For this reason, individual chance performance should be measured against a few different numbers, including team averages, linemate averages, and averages per shift (40 seconds). This allows players to be fairly evaluated against the overall performance of their teammates and more specifically to the players they play with on a frequent basis.
I certainly understand and appreciate that there is much more to hockey than scoring chances, however I feel that looking at and tracking scoring chances is the most effective way to get an overall view of a team’s performance. It measures the ability of the player and the team to perform when it matters most.