How “fancy” metrics like Corsi and PDO affect player values
HOCKEY IS FINALLY catching up to a movement that has permeated all major sports. Call it “advanced stats,” “fancy stats” or “moneypuck.” It all boils down to the same thing: more accurate information about a player’s contributions to his team, going deeper than common numbers like goals and points.
Thanks to websites like behindthenet.ca and extraskater. com, fans have all the information they need on a player or team right at their fingertips.
Corsi is the most common advanced stat in hockey. Current Blues goalie coach Jim Corsi started it when he was with Bu alo. He took the plusminus stat, which is generally considered useless by poolies, and expanded on it. Rather than goals-for versus goals-against, it looks at shot attempts-for versus shot attempts-against. So, Corsi is missed shots plus blocked shots plus shots on goal. It provides a greater sample size, which better indicates how a player’s team controls the play when he’s on the ice.
We can also now look at info such as a player’s zone starts over any portion of a season. What percentage of shifts did he start in the o ensive zone, and how many of those ended in his own zone? Then there’s CorsiRelQoC (relative Corsi quality of competition), which measures the quality of opponents a player lines up against. This stat takes his Corsi and adjusts it relative to a team’s Corsi while he was o the ice, then adjusts for the quality of a player’s opponents. CorsiRelQoC uses an average of this number for the five players on the opposition who are on the ice against the player you are studying. A higher number indicates that your player is playing a higher level of competition. This statistic is generally regarded as the soundest measurement of a player’s competitive value.
As far as advanced stats go, when it comes to fantasy hockey, they aren’t common and may not be for several years. That many leagues have introduced hits, blocks and faceo wins suggests poolies are ready for the new wave. Corsi will probably come next, replacing plus-minus in fantasy leagues to create more realism. It’ll creep into our game as soon as online pool managers make it a common option.
The advanced statistic I look at the most in my pre-season prep work is dubbed “PDO.” What it stands for is a mystery – its creator Brian King admits that – but it’s a measure of luck. Theory says if you were to add up the team’s shooting percentage when a player is on the ice with a team’s save percentage when he’s on the ice, the number will, over time, approach 1,000. A player with a number of 950 is probably in for some better luck in the season ahead. And by the same token, a player with a number of 1,085 has been enjoying a lopsided amount of lucky bounces. So if you take the PDO numbers that jump out at you the most, you can drill down further and look at the team’s shooting percentage while the player is on the ice. If that number is 4.5 percent, then obviously the chances of them getting better luck in the season ahead are strong.
Looking at players with at least 40 games last season, here’s a sample of those whose production will increase or decline, according to their PDO.
Jim Corsi created ‘Corsi,’ the most famous advanced stat. It tabulates shots directed toward an opposing goal, including missed nets and blocked attempts.