My next sabermetrics and hockey post is to correct the top individual player’s Corsi Ratings for team effects. One look at the top Corsi Ratings from last season shows that there are an unreasonably high number of Chicago Blackhawks represented (the top three and six of the top 20 are Hawks). This is because Chicago has the best team Corsi in the league and it is easier to have a good individual number when all your team has good ratings.
In order to adjust these Corsi Numbers for team effects we use the same method used for counting +/- ratings. Thus we can rank individual player’s puck possession via Corsi (difference in shots directed at goal by a player’s team and their opposition in 5 on 5 situations) without team effects distorting our numbers. We still have issues from individual player roles (some are used more defensively and others offensively) which we can try to remove with a further adjustment.
Last year the Colorado Avalanche grabbed the final playoff spot in the West Conference with a 43-39 record (9 regulation tie points). They did so largely by a strong start. They had a 10-3 (2 regulation tie points) record at the end of October. They did this despite a low team Corsi rating. They allowed 699 more shots directed at their net (shots on goal, missed shots and blocked shots) than they managed to direct at their opponent’s net in 5 on 5 situations. This was the third worst in the NHL (only Edmonton and Florida were worse) and this shows that Colorado was not strong at puck possession. In fact, the only team that had as high a Corsi as Colorado’s was negative was the Stanley Cup champions in Chicago.
How did Colorado manage a playoff berth with such poor puck possession? Can they expect to repeat it in the future?
The Toronto Maple Leafs had a poor season last year. They finished with a 30-52 record (with 14 regulation tie points). This put them in second last in the NHL. However there are signs that they will be a better team than that record shows. One very encouraging one is their third best team Corsi rating. In five on five situations they directed the puck at their opponent"s goal significantly more than their opponents directed it at the Leafs goal. The only teams in the NHL that had a higher edge in their favor were the Chicago Blackhawks and the Detroit Red Wings. The Toronto Maple Leafs did well in terms of puck possession.
These numbers can be looked at a bit skeptically because Toronto was frequently behind in their games and thus pressed hard offensively to catch up, while their opponents went into a defensive shell. In short, game situations gave them a better chance to possess the puck. That said it still shows that Toronto was a pretty good team in 5 on 5 situations. No other bottom feeding teams showed nearly as good team Corsi ratings.
In some sabermetrics and hockey posts this summer, I have listed the top 20 and worst 20 players by Corsi when listed as counting numbers and the top 20 and worst 20 when listed as rates. The biggest error in attributing the positions of players on these lists to their playing ability comes from team effects. Players on good teams tend to have good Corsis and players on bad teams tend to have bad ones. In order to take this into account we need to know how the various NHL teams stacked up with respect to Corsi.
Corsi is the difference in shots directed at goal (shots on goal, missed and blocked) taken by a team and those taken by their opponents. In this study, only 5 on 5 situations are looked at.
Over both of the last two years, I have noted that Ryan Johnson of the Vancouver Canucks has the worst Corsi when viewed as a rate stat among players with 50 or more games played. Here are the worst Corsi rates from this year and here they are from the year before. Notice that as Vancouver improved in the standings, Ryan Johnson’s Corsi rate actually got worse.
There is some resistance from Vancouver and the league in general to looking at this stat and concluding that Ryan Johnson is a liability to the Canucks. Here is Nucks Misconduct’s responce when I suggested Ryan Johnson had played himself out of the NHL. I was wrong that he did that last season, it looks like he played himself out of the league this year and only should have done it last year, but the Canucks continued to play him another season.
Since my last sabermetrics and hockey post was the top 20 Corsi rates, it is logical to continue with the worst 20. Corsi ratings are the difference in the number of shots directed at goal (shots on goal, missed shots and blocked shots) by a team and their opposition in 5 on 5 situations. They are a strong measurement of puck possession, as a team with possession of the puck tends to shoot a lot. As we are looking at rates in this post, each player is normalized by the number of 5 on 5 minutes that he plays. Thus players who do not play many minutes a game and thus cannot get a large Corsi by counting methods may appear here. In fact this is more likely on a worst players list than a bets players list, as teams will want to play their best players as much as possible while hiding their worst players.
The act of signing restricted free agents to offer sheets is getting more common under the current CBA. Before the lockout, it was pointless. You would sign a player and in almost all cases, his original team would match the salary and all you managed to do was run up NHL salaries and create a higher salaried comparable player for those on your team. Now that limited salary cap space makes it more likely that other teams cannot match offer sheets (particularly if they are used on teams nearing the salary cap for next season), there is a better chance of actually obtaining the player you sign to the offer sheet and even if you do not get him, you have even further reduced the salary cap flexibility of a rival. I do not believe that there really was a “gentleman’s agreement” to not sign players to offer sheets. It is an idea born out of the media failing to explain the lack of offer sheets before the lockout and upon Brian Burke’s bluster when Anaheim was hit with the Dustin Penner offer sheet.
With that in mind, the San Jose Sharks have signed Niklas Hjalmarsson to a four year offer sheet that will pay $14 million.
I think it is usually more meaningful to look at counting stats than rate stats when determining the best players in the NHL. As such I have listed the top 20 and worst 20 player’s individual Corsi Ratings from last season, where Corsi is the difference between the shots directed at goal (on goal, missed net and blocked) for a player’s team and the opposition when the player is on the ice in 5 on 5 situations. This is a strong gage of puck possession in NHL games.
Throughout this process, commenter GoPens has been asking about why I like counting stats over rate stats. I think the best way to explain this is to give the top 20 players by Corsi rate (Corsi per minute) and compare with the top 20 by counting stats.
Yesterday it was announced that Evgeni Nabokov signed a four year contract with SKA St Petersburg in the KHL. Nabokov is a good NHL goalie. He was named to the First Team All Star in 2008. He is better than many goalies who are employed in the NHL, including many starters. He is a better goalie than either of the pair his former NHL team, the San Jose Sharks intend to use next year. There should be little controversy in claiming he is a better goalie than Antero Niittymaki or Thomas Greiss.
If Nabokov is such a good goalie why was he pushed out of the NHL? Largely it comes down to a finite number of NHL jobs available. The salary cap has forced teams to economize in some positions and the prime goaltending jobs filled up with players who will be paid less than the price Nabokov demanded (and deserved based on his past history). When jobs began to be filled and Nabokov saw other big name goalies in Marty Turco and Jose Theodore remaining unemployed as well, he opted to return to his homeland to play in the KHL.
I am continuing my look at sabermetrics and hockey today. Yesterday, I listed the players with the top 20 Corsi ratings as counting numbers and today I will list the worst 20. Corsi is a measure of the difference between shots directed at goal (on goal, missed net and blocked) by a player’s team and his opponents. It is used as an alternative for +/- because it encompasses far more events than only goals scored and is an indicator of puck possession.
The players scoring worst in Corsi Ratings are poor at puck possession. They also likely play on teams that are poor at puck possession and are often used in defensive roles, where it is expected that the opposition team will most likely control the puck. While being on this list is not a sign of a good player, it is not necessarily a sign of a poor NHL player. Other factors can have come into play to keep the rating low.
About The Puck Stops Here
Who am I? A diehard hockey fan.
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