Wednesday, October 07, 2009

Oiler Team Scoring Chances and Reasonable Expectations for 09/10

Since all points in the standings are derived from scoring goals and all goals emanate from scoring chances, the New York Rangers coaching staff emphasizes the ability to create scoring chances.

Kevin Leonard, NYR Database Designer, c.1992

I like rolling averages, it smooths out the bumps in the season that are caused by tough stretches of the schedule or puck luck. This spring I posted a few items on the Oilers' scoring chances, all concerned the individual player on-ice scoring chances. This post is the first looking at the team totals.

"ScoringChance%" is he percentage of the total even strength scoring chances in the game that were owned by the Oilers. So if, over twenty games, the Oilers racked up 200 EV scoring chances, and the opposition tallied 300 EV scoring chances ... then the Oilers would lay claim to 40% of the scoring chances over the stretch (200 of 500).

"Corsi%" is calculated using the same reasoning, as is EV "Goals%".

Corsi% is our best guess at the extent of territorial advantage held by the Oilers in the previous 20 games.

I think it speaks for itself. Here is an enlargement of the 40% to 60% band:

So, quite clearly Corsi% (or any of the shots metrics for that matter) ends up giving us a clear indication of scoring chance percentage. Using 20 game rolling averages as above, they are almost on top of one another.

On the year as a whole:
ScoringChance% = 47.7%
Corsi% = 47.8%
Goals% = 51.0%

The Oilers got a bit fortunate with the shooting/save percentages, mostly due to the fact that Roloson had a terrific year at even strength. (In fairness, that gets balanced out a bit by some bad puck luck on the PK, in a fairer universe the 0809 Oiler penalty kill would not have been nightmarish, merely terrible).

The Goals% (yellow line) may look volatile, but EV goals are rare birds in NHL, so it always will be similarly wiggly for all teams in all years. If you drew a straight red line at 51.0%, then coloured in the spaces in between the yellow curve and that red line, filled them in with black dots (Jim Albert's BLACKstat) then the black area would represent the streakiness or inconsistency of the Oiler Goals%. And in 753 of 1000 parallel universes the Oilers would be expected to be a touch MORE streaky with Goals% than they were in 0809.

The Oilers just weren't a very good even strength hockey team in 0809. And they aren't this year either.

There is a downward trend in the ScoringChance% starting early in the back half of the season, and it never recovered. I'm not sure when Hemsky got concussed or when Visnovsky's season ended, but it must be thereabouts. Both are terrific players when healthy, and neither appear to be fully fit at the moment, so this next stretch could be tough for the Oil.

On the other hand, Gagner and Cogliano should improve, Gilbert and Grebeshkov too, Penner even. Though, as RiversQ showed in an earlier post, that progression is wildly erratic. And the guys who are on the hard downslope of their careers (Moreau, Staios, Strudwick, Pisani) can't do much worse this season than last. Plus Comrie is a good addition to my mind, or maybe it's just the thrill of seeing the Oilers sign someone with a good chance of beating his contract price.

My conclusion: With good health, the Oilers should be better this year than last, maybe even become dead average at outchancing (50%). Let's dare to dream.