Wednesday, January 11, 2012

On the Blue Jackets' Struggling Power Play

Yesterday I made a short post on the Blue Jackets' low PDO, making the point that we should expect the Jackets to have a much better second half as their shooting and save percentages climb back towards the mean. In the comments, Rob Vollman brought to my attention this Hockey Prospectus article by Timo Seppa, which brings into question Columbus' Power Play production dropoff after the transition from Ken Hitchcock to Scott Arniel. Timo asserts that
Arniel's track record wasn't favorable, particularly when compared to that of former coach Ken Hitchcock. In many aspects, the Blue Jackets had taken steps backwards since his departure, and they'd done no better than tread water elsewhere.

One example is on the power play. Never a particular strength of the Jackets—you need star players to have a truly upper echelon man advantage—the production of several key contributors had taken a highly visible nosedive in a year-and-a-half under Arniel's watch:

In other words, the dropoff in scoring under Arniel signifies a dropoff in overall power play production since Hitchcock left. This is a fine assertion to make judging by what these numbers tell us on the surface, however, I actually believe the Blue Jackets were a better PP team under Howson than Hitchcock. Let's take a look at why with some numbers via Behind the Net and NHL.com:

Season5v4 SF/60 (NHL Rank)5v4 SH%
2007-200844.8 (24)11.4
2008-200947.2 (25)9.4
2009-201051.8 (12)12.9
2010-201153.7 (8)8.9
2011-201253.5 (6)9.1

Timo only looks at '08-09 onward, but I decided to include '07-08 under Hitchcock since I don't have the ability to break down the '09-10 season with splits before & after Hitchcock was let go. Regardless, it is clear from these numbers that Columbus actually increased their shot rate on the PP under Arniel to levels that the Hitchcock-coached team were never able to reach.

How, then, could have Columbus actually posted better scoring results under Hitchcock? The answer is simple: shooting percentage. As Jared has pointed out, there is a tremendous amount of luck involved in shooting percentages, especially in small sample sizes. When you're looking at results on the power play, it is important to keep in mind that PP shots are going to represent about 1/4 (or less) of a team's total shots throughout the regular season, enough where luck is still going to be a major factor in scoring goals. The fact of the matter is this: the shots were going in under Hitchcock, and they weren't under Arniel. Regardless of whether Rick Nash was playing in front of the net or on the half-wall, the team was still unlucky to shoot at such low rates under Arniel, which resulted in lower point production for the team.

Though there were definite shortcomings in Arniel's system, e.g. going into an absolute shell when up by 1 or 2 goals, this is more evidence that he was yet again on the wrong side of luck.

2 comments:

  1. Good stuff, but check out what Tom Awad had to say today.

    http://www.hockeyprospectus.com/article.php?articleid=1228

    In part: "You don't fall short 116 goals purely by bad luck, as this would be a 3.5 standard deviation event, having roughly 1 chance in 5000 of occurring by chance"

    Note: the quote refers to the team on a whole, not just the power play.

    Also, I think you can get the mid-season shot split by using timeonice.com.

    Columbus: popular topic!

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  2. I definitely agree with Tom's article quite a bit more. I don't think anybody would disagree Columbus has been unlucky in that stretch, and throwing their goaltending into the mix probably explains quite a bit more. I wouldn't be surprised at all if their true 'finishing talent' fell well below league average, so that could explain some of it as well.

    However, on the PP alone, we're only talking about differences of 10-15 goals in 400-500 shot samples which are extremely luck-driven. That's why I think using PPP/60 isn't an effective measure to judge PP success over that span. When you throw in even strength, it gets a lot less noisy.

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