ADVANCED STATS 101
In hockey, teams are often given labels to identify their style of play.
"Team X is a hard-working, grind-it-out team."
"Team A is a puck possession team."
One of those two characterizations can be quantified with data, and it's the latter.
Advanced statistics in hockey are becoming widely popular and have become more refined over the past few years. Instead of tracking goals (as plus-minus does), possession metrics take note of shot attempts for and against, and in doing so, can show patterns and trends when certain players are on the ice.
By tracking what teams do when they have the puck, we can determine things like puck possession, scoring chances, how teams spend their zone time, and more.
For team-based analysis, the common terms in the lexicon are Corsi and Fenwick (we'll talk more about these in a moment). For players, you'll primarily refer to Corsi, deployment metrics and PDO (also something we'll cover down below).
Regularly-used and kept statistics, such as time on ice (TOI), save percentage and shooting percentage, are also applied in advanced stats but used in different ways. PDO, for example, combines shooting percentage and save percentage to show scoring trends for teams and players - i.e. are hot goal-scoring stretches just streaks, or is this indicative of a long-term pattern?
Here's a brief rundown of the terms you'll see associated with hockey analytics (via the now-defunct ExtraSkater.com):
CORSI - Named for former Buffalo Sabres goaltending coach Jim Corsi, who tracked shot attempts for and against taken by a team or player. In other words, it's the sum of a team or players's goals, shots on net, shots that miss the net, and shots that are blocked. It's used as a proxy for puck possession. For players, we usually measure "on-ice" corsi, or all of their team's shot attempts while they're on the ice.
FENWICK - Named for blogger Matt Fenwick, it's very similar to Corsi and in most cases, can be considered interchangeable. Fenwick is the number of unblocked shot attempts by a team or player. It's the same as Corsi, but excludes shots that are blocked. It's used because over many games it's a slightly better proxy for possession than Corsi. It's not used exclusively instead of Corsi mainly because over smaller sample sizes, the larger Corsi number is more accurate in reflecting puck possession.
DEPLOYMENT - Player deployment metrics are used to track how players are used in game situations. Most common are zone starts, which show how often a player begins his shift in the defensive zone, offensive zone, or neutral zone. You'll see these abbreviated as DZS%, OZS% and NZS%.
TIME ON ICE (TOI%) - The percentage of his team's total ice time that a player is on the ice for.
PDO - A combination of shooting percentage and on-ice save percentage.
So, those are the basics of advanced stats - sometimes called "fancy stats."
For a comprehensive look at analytics and how they're applied in hockey, we recommend the following websites as top-notch resources:
On the web:
Shutdown Line (www.shutdownline.com)