One of the more interesting players last year in terms of sabermetrics was Zenon Konopka who played with the New York Islanders and signed this summer with the Ottawa Senators. He winds up near the bottom of raw Corsi lists but played a tough role on a poor team.
Commenter steviestevie saw this and commented It’ll be interesting to see what Konopka’s performance looks like when more numbers are taken into account. He’s not exactly a world-beater, but he was pretty much thrown to the wolves taking tons of d-zone faceoff for a club whose transition game last year can best be described as “Is Grabner on the ice? No? *#&$%^!” in the worst team adjusted Corsi list.
Last week I published the worst 20 players by team and zone adjusted Corsi ratings in 2010/11. Perhaps the most significant player on the list is Robyn Regehr, then of the Calgary Flames and now a Buffalo Sabre. Regehr has represented Canada internationally in both the Olympics and the World Cup, so he must have been a top player at one time. Regehr is 31 years old, so perhaps he is starting to slow down - though many players remain at all star level at much higher ages than that.
Regehr had a relatively poor raw Corsi, which was the worst on his team. Calgary had a better than average team Corsi so this makes his team adjusted rating worse. Regehr played against a tough quality of opposition. He had the third toughest quality of opposition of any defenceman who played a significant number of games last season (behind Nicklas Lidstrom and Brent Seabrook), but he was not used preferentially in his own zone.
In an effort to put Corsi ratings into context to make sense of them, I have corrected the raw ratings for both team and zone start effects. Team effects are important because good teams will tend to attempt more shots and have fewer shots taken against them than weaker teams. Zone start effects are important because players who are on the ice for offensive zone faceoffs will tend to take more shots and players who are on the ice for defensive zone faceoffs will tend to have more shots against. This makes a pretty good individual indicator of puck possession abilities. The top players had good seasons and the worst players had weak seasons.
One look at the worst player list shows that Cam Fowler of the Anaheim Ducks was the worst adjusted Corsi player in the league. His -227.12 team and zone adjusted Corsi is the worst among players who played 50 or more games with one team in 2010/11. It is entirely possible that Paul Mara and Brent Sopel did even worse in terms of puck possession, but as they played with two different NHL teams in 10/11, this makes their team adjustments less certain so they are removed from the study.
As I continue looking at sabermetrics and hockey, I am looking at the worst 20 players by team and zone adjusted Corsi ratings. This is the converse to the top 20 players list that I have already written about.
This group of players did very poorly in terms of puck possession in 2010/11. The list is found by measuring the raw Corsi rating of all players in the league (this is the difference between attempted shots for and against when a player is on the ice at 5 on 5). That number is then adjusted for team effects and for zone starts (whether or not a player is on the ice for faceoffs in the offensive, defensive or neutral zones). This provides context to give a pretty good individual assessment of an individual player’s puck possession success. In principle other effects can be taken into account including quality of linemates and opposition players, but this is more complex and has less of an effect on the numbers.
Corsi-based analysis is a very strong way to better understand hockey. Like any statistic, it makes sense when put in the proper context. Zdeno Chara in 2010/11 is a very good example to show this.
When we look at the top 20 raw Corsi ratings, Zdeno Chara is not on the list. We adjust this list for team Corsi ratings because Corsi ratings (or any other puck possession stat) is really a rating of all of the players on the ice. Players on teams that have good puck possession numbers will have better raw numbers than those on weaker teams. This is something that needs to be taken into account to put the number in context.
I continue my sabermetrics and hockey posts by looking at team and zone adjusted Corsi ratings. This is a pretty good ranking of puck possession among NHL players in the 2010/11 season. The Corsi rating is the difference in attempted shots (shots on goal, missed shots and blocked shots) while a given player is on the ice in 5 on 5 situations. A team adjustment is then made to try to be able to compare between different teams. In order to correct for zone starts we must make an extra team adjustment to account for the given team’s zone starts (does the team tend to start more shifts in the offensive or defensive zone?) and then adjust for individual player zone starts at a rate of 0.8 Corsi events per excess zone start.
The league leader last year in excess defensive zone starts was Steve Ott of the Dallas Stars. He was on the ice for 326 more defensive zone faceoffs than offensive zone ones. This shows that he played a pretty tough defensive role for Dallas. Despite that, Steve Ott did not appear on a single Selke Trophy ballot. Are these facts inconsistent?
Ott played a pretty tough defensive role, but he did not receive recognition for it. Part of the problem is one of recognition. The Selke Trophy is voted upon largely by reputation. Increasingly, offensive totals are taken into account and Ott had a 12 goal, 32 point season which is not particularly spectacular.
I continue my sabermetrics and hockey posts by looking at the players with the largest excess of defensive zone starts. These are players who play tough defensive roles with their teams and as a result their offensive numbers and puck possession numbers will suffer. In order to compare them with players who have more traditional usage, this must be taken into account. It is the opposite of the offensive zone starters that I have already looked at.
Here are the 20 players with the highest number of excess defensive zone starts in 2010/11:
There are many reasons why players suffer sophomore jinxes in the NHL. One of the more predictable reasons is that the player was treated with kid gloves in his rookie season. His team was careful not to put him in a situation where he would be “over his head”. Now in a second season, he has to play a bigger role with his team and he is no longer as well protected as there is a new rookie to play the protected role.
One way to identify protected players is to look at offensive zone starts. Some players were played preferentially in offensive situations and not in defensive ones. Hence they will have a significant imbalance of offensive zone starts over defensive ones.
Two rookies placed quite high on the offensive zone start list. Derek Stepan of the New York Rangers placed ninth and Kevin Shattenkirk of the St Louis Blues placed tenth. This makes them strong candidates for a sophomore jinx.
Yesterday I posted the top 20 players by offensive zone starts. The three players who are well ahead of the rest of the pack are Daniel Sedin, Henrik Sedin and their linemate Alexandre Burrows. Daniel Sedin has over 60% more excess offensive zone starts than any player on any other team.
The Vancouver Canucks are the team that most uses offensive zone starts strategically. They make more effort to start their best offensive player’s shifts in the offensive zone and have defensive players like Manny Malhotra who get the excess defensive zone starts. This increases the Vancouver Canucks team offence. This increases the offensive numbers that the Sedin line gets.
About The Puck Stops Here
Who am I? A diehard hockey fan.
Why am I blogging? I want to.
Why are you reading it? ???