In this summer’s look at sabermetrics and hockey, I have looked at the Corsi Number as an alternative to +/- ratings. Because Corsi Numbers include far more events (all shots directed at the goal) they may be more accurate than +/- which only includes goals scored, as long as the events included are meaningful (are blocked shots and missed shots meaningful?). The best source for Corsi Numbers online is behind the net. It treats Corsi Numbers as a rate stat (per unit of time). I think a more reasonable place to start in analysis is with the raw counting numbers. I have already listed the top 20 players by Corsi Number. Here are the worst 20 Corsi Numbers in the 2008/09 regular season.
When I listed the 20 players with the top Corsi Numbers in 2008/09, the name on the list that most surprised me was David Moss of the Calgary Flames. Moss ranks tenth in the league last year with a +343 Corsi. Moss is not a reasonable choice to be called the best player on his team, while any of the other top 20 players all might be (at least if you neglect other teammates who made the top 20). Moss is a 25 year old who completed his third NHL season (his first full NHL season). He played largely on the Flames third and fourth lines, but managed to chip in 20 goals and 39 points. This placed him tenth in Calgary’s scoring list. The secret to Moss’s success is he is the best puck controlling player who did not play on the top two lines under Mike Keenan.
Ever since there stopped being a valid player transfer agreement between the NHL and the Russian Ice Hockey Federation, both sides have been fighting over players. The first major battle was over Alexander Semin who played in Russia during the lockout year and the year after it despite a valid NHL contract. That was sorted out and he came to the NHL. Though he has become an NHL star since then, he was not one at the point of the fight over his rights. The Russians attempted to fight the transfer of several players to the NHL including Alexander Ovechkin and Evgeni Malkin, but the NHL was able to get any player they wanted and Russia was only successful in getting some NHL rejects (such as prospects Roman Voloshenko and Igor Grigorenko). The NHL had been able to get their way in any important case until Alexander Radulov left Nashville for the KHL.
In this summer’s look at sabermetrics and hockey, I have introduced the Corsi Number as an alternative to +/- ratings. Let’s take a look at some of the players with the best Corsi Numbers from the 2008/09 regular season. The best online source for this information is behind the net, but it treats Corsi Numbers as a rate stat (giving them per minute of ice time). I think it is a much more logical starting point to look at the raw counting numbers. This is how we most frequently view +/- ratings and should be best comparable to Corsi Numbers. In the adjustment process, we may wish to treat them as rate stats, but not at this point.
Here are the top 20 Corsi Numbers from 2008/09:
I like to write a career perspective when future Hall of Famers retire. Today Joe Sakic is expected to announce his retirement in a press conference in Denver. This retirement is one that I feel close to because I grew up near Joe Sakic and first met him (though I doubt he would remember) when I was a four or five year old child and Sakic was a slightly older child starring in Burnaby Minor Hockey.
Joe Sakic was born on July 7, 1969 in Burnaby, British Columbia. He grew up playing in the Burnaby Minor Hockey Program. He was first noticed by scouts in 1985/86 playing for the Burnaby Selects of the BC Amateur Hockey Association when he scored 156 points in 80 games. This was good enough to get him a three game tryout with the Lethbridge Broncos of the WHL. Lethbridge moved to Swift Current the next season and this is where Sakic became a junior star. In his first full junior season, Sakic scored 133 points in 72 games and was named to the WHL East Second Team All Star, WHL East Rookie of the Year and WHL East Player of the Year. This was good enough to get him selected by the Quebec Nordiques 15th overall in the 1987 entry draft.
In this summer’s look at sabermetrics and hockey I have began by looking at +/- ratings and the results of a couple standard methods of their adjustment. +/- ratings are sometimes considered a problematic starting point. One problem is “signal to noise” there may be slightly over 100 goals scored in even strength for a given player in a given season. Their +/- is the difference between the goals for and the goals against. If there are a few fluke events they can carry the majority of the signal (i.e. if a player is on for a few fluke goals those goals can greatly influence their +/-). One way to try to get around this is to increase the number of events we are looking at. Buffalo Sabres goaltender coach Jim Corsi has pioneered another metric. Why not keep track of all even strength shots directed at the net both for and against a team when a player is on the ice. This includes goals scored, shots on goal, blocked shots and missed shots. The NHL keeps enough data in its games online that this can be calculated for each game. The main benefit of this method is that it gives roughly sixteen times the number of events for a player that standard +/- does. This is intended to increase the signal to noise (in experimental physics any counting number has an experimental error that scales with its square root so in principle the Corsi Number could be four times better).
I have been looking at +/- ratings and their adjustments in some of my recent posts. I have written about adjusted +/- as a counting stat and given the top 20 and worst 20 players from last season by this method. I am comparing it to the rate stat adjustment that Gabe Desjardins of Behind the Net does. I have listed the top 20 players by this method. Here are the worst 20 players last season by this method of +/- adjustment (with a minimum of 50 games played).
The Chicago Blackhawks appear to have made a very big procedural mistake. Six of their players, Cam Barker, Troy Brouwer, Ben Eager, Colin Fraser, Aaron Johnson and Kris Versteeg (many reports have called this group the Chicago Five - it is unclear if that means one of these six is not involved), may have not received qualifying offers correctly. If this is the case, these players would become unrestricted free agents. Apparently, these players had their qualifying offers mailed to them on June 29th. The deadline for players to receive their qualifying offers is 4PM ET on June 29th (early stories incorrectly listed July 1st as a deadline). Usually, qualifying offers are sent by courier or by fax to the player’s agent, but this was not done in these cases.
I have written about the top 20 and worst 20 adjusted +/- ratings when adjusted as a counting stat from last season. This is not the only way to adjust +/- ratings. Gabe Desjardins of behind the net calculates them in a different manner. He calculates the */- per minute when a player is on the ice and his team’s +/- per minute for the team when a player is off the ice and compares them to make an adjustment. This uses +/- as a rate statistic. As a result, his method is better at finding players who do not play as many games or as much playing time than the previous method.
Here are last year’s top 20 adjusted +/- ratings by this method (among players with 50 or more NHL games played):
One question I have tried to think about is how good a team would be if they could sign unrestricted free agents in order to completely fill their roster. This summer and last summer I made 23 man all star rosters of UFA players. Assuming one team signed all of those players in a given year, how good would they be? 22 of the 23 players on the 2008 team signed in the NHL (with Jaromir Jagr signing in the KHL). They had a total salary cap hit of a little over $101 million for the season. Given a $56.7 million NHL cap this team is clearly unfeasible as an NHL club.
In order to get a bit of a handle on how good this team might have been, we can look at their 2008/09 NHL numbers
About The Puck Stops Here
Who am I? A diehard hockey fan.
Why am I blogging? I want to.
Why are you reading it? ???