Tom Awad at Puck Prospectus has been making a habit out of adding interesting statistics to the tool kit with which NHL fans can assess their respective clubs. GVT is a useful counting stat that gives us an idea of a player's value and contribution to the team in terms of goals (which equate to wins in the NHL). Unfortunately, not every player produces points, so GVT is sort of slanted against more defensive players.
Plus/Minus seems relevant to a lot of people but stat geeks are moving away from it because of it's inability to account for individual contributions. It has more value over time but it's hard to see how much sense it makes in the smaller sample size of an individual season.
Corsi numbers are being used more and more to assess puck possession but they don't do a wonderful job of accounting for the quality of scoring chances. Again, we might want to use something slightly different.
Another interesting statistic that Awad has recently sussed out is something he's terming Delta. Basically a statistical combination of the ideas of Corsi numbers and +/- Delta weights every shot on the ice (the Corsi portion) on the basis of the expectation of whether or not said shot will result in a goal (the +/- portion). The shot-quality is determined using models around shot distance and location on the ice as well as the game score. I won't get into a much more detailed explanation but if one is desired it can be found here.
The whole purpose behind the exercise of determining this new statistic is basically adjusting the concepts around puck possession in terms of ability to generate and prevent good scoring chances. I am particularly interested in adjusted Delta Values, which control for the various players on the ice with a given player, as well as the game situation in terms of current score. In the end, we get a fairly solid determination of the quality of a given player.
So let's look at how the Leafs Forwards compare using this new stat shall we?
First let's examine the forwards on next year's Leafs using their combined Delta SOT values in 5-on-5 situations for the past 3 consecutive seasons (Tom Awad has tabulated the Delta values and made adjustments for every NHL player from the past 3 years). The first column (Delta) is the raw Delta score for the player at 5-on-5. A value above zero indicates that the number of expected goals with the player on the ice was in his team's favour rather than for the opposition. The Delta QS (quality of situation), Delta QO (quality of opposition), and Delta QT (quality of teammates) are all adjustment factors used to determine Delta SOT. If the Delta QS, QO, or QT value is positive then that condition was working AGAINST the player, so a +QS means a player had more defensive than offensive zone faceoffs, a +QO means the player faced more difficult opposition than the average player, and a +QT means lower quality teammates on the ice hampered the generation of scoring chances. All of these conditions will depress the raw Delta score observed for a given player, so the Delta SOT is adjusted upwards to compensate.
Negative adjustment values result if a player has more offensive than defensive zone faceoffs, if the player faced easier or less difficult competition than average, or if they played with teammates that are above average. All of these conditions should work to elevate the raw Delta score for an individual, so the Delta SOT is adjusted downwards.
A Delta SOT score of zero would be a perfectly neutral player. They give up and produce chances of identical quality and number. Obviously virtually no players will accomplish this feat, so any player on the positive side of the docket produces more good scoring chances than they allow, while players on the negative side allow more good scoring chances than they produce.
|Player||Delta||Delta QS||Delta QO||Delta QT||Delta SOT|
Generally speaking, the Leafs forwards next season have limited experience facing up against top competition. They also seem to generally get out-chanced when on the ice. The exceptions to that so far are Mikhail Grabovksi, Kris Versteeg, Nikolai Kulemin, Phil Kessel, and to a very limited extent, Tyler Bozak and Fredrik Sjostrom. Colby Armstrong has exhibited an ability to be productive in the past, but he has been lining up with some horrible teammates, against some difficult competition down in Atlanta, so it hasn't really come out in the wash.
At the horrible end of the scale are John Mitchell (thus further indicating a selection of very poor shot choices and generally poor defensive hockey sense) and Colton Orr. The Leafs enforcer brings something else that is valued by management to the table on a regular basis, so he gets a bit of a pass, and he doesn't play a lot so it's not a big deal.
Mitchell on the other hand is an exhibit in negligence. He is a generally negative player when on the ice, and based on these numbers, he is consistently out chanced while on the ice. This likely stems from a combination of poor defensive coverage, and his general tendency to stick handle the puck away from anything resembling a dangerous situation from the opposition's perspective.
I will be posting similar data for the Leafs defensive group tomorrow. Feel free to contribute comments below.