Coaching Effect Continued

A few days ago, tentative as a newborn horse, I took my first steps towards bashing together some statistical analysis of my own. I was trying to help address one specific issue that might be relevant to the upcoming Leafs’ season: against which statistical measuring geegaws, come the end of the season, should we assess the performance of the team’s coaching staff?  In other words, what numbers should I look at to try and figure out whether Ron Wilson and his staff are doing a good job?

The first conclusion I came to was that it is incredibly difficult,  possibly related to some sort of an international conspiracy, to embed any kind of a chart in WordPress.  The second, perhaps more illuminating conclusion was that there appear to be wide year-to-year, essentially random, variations in teams’ goals for and goals against ledgers.  Absent an enormous – on the order of 20% or more – change, therefore, it is probably not possible to confidently ascribe any meaning to differences in the year to year totals.  In other words, if you’re trying to divine something about the efficacy of an NHL team’s coaching staff, you might as well dig through goat entrails as comb through the Goals For and Goals Against numbers.  They’re likely equally informative on the subject.

After I posted the raw data, it occurred to me that the changes to last year’s Leafs roster following January 31st (hereinafter known throughout the land of Blue and White as “Emancipation from Vesa Toskala Day”) might illustrate the point too.  It occurred to me that, given the large turnover of the roster on that day (White, Hagman, Mayers, Blake, Stajan and Toskala all out, Phaneuf, Giguere and Sjostrom in, plus help summoned from the minors), you might look at the first 57 games as one season, and the final 25 games as another mini season.  I thought this would be interesting because, given the Olympic break and the compressed schedule (25 games in 68 days, including the three week break, so really 25 games in about 47 days), it was not very likely that any substantial on-ice instruction could occur in the post-trade timeframe.  In other words, examining the pre- and post-trade data separately comes very close to affording an opportunity to examine two data sets in isolation from the coaching effect – because no significant coaching of a substantially changed team could have occurred following the trade.

Based on the subtraction of the alleged goaltending of Vesa Toskala alone, I felt confident that the Leafs’ goals against numbers would be vastly improved in the post-trade period.  A quick look at Figure 1 (oooh, how text book-y of me) shows that the data bear out that assumption:

Vesa Toskala's Goaltending Ought to be Tried for Crimes Against Humanity
Fig. 1: Things Got Better When Dion Came and Toskala Left

As you can see, I’ve taken the actual data observed in both the pre- and post-trade period and prorated them over 82 games to try and get to a place where we can compare apples to apples.  Interestingly, the Leafs scoring prowess *cough* remained essentially undisturbed, as Dion Phaneuf’s Leafs continued to put biscuits in the basket at almost exactly the same rate as Team Stajan (213 GF vs. 214).   As suspected, goals against took a nose-dive when Toskala was deported, changing the Leafs from a 283 goals against squad to a team that was on pace to have given up 216 over an 82 game schedule.

First things first: to go back to the original point of the exercise, the Leafs changed from a team that would surrender 283 goals over an 82 game schedule to a team that would cough up 216, and that had to have happened in an atmosphere when the coaches were unable to get the team together for any substantial on-ice drills or systems instruction.  In other words, the goals against dropped by approx 67 total goals or .8 GA per game without any significant contributing coaching effect

Some other things caught my eye about the data, though:  to put the apparent change in the Leafs’ defensive prowess following the Phaneuf and Giguere trades, remember that the Leafs’ went from a 283 GA pace to a 216 GA pace.   The Edmonton Oilers, who finished in 30th place in the league last year, and who finished the season with the league-worst goals against total, gave up 284 opposition tallys.  By contrast, 216 goals against, would have put the Leafs tied with Detroit for the 8th best GA number in the league, behind only San Jose, New Jersey, Phoenix, Chicago, Calgary, Buffalo and Boston.  Among that group, only Calgary failed to reach the playoffs.  That would be the same Calgary team that finished the year with Matt Stajan and Vesa Toskala on its roster.  See how these things come full circle?

Lastly, I hadn’t realized that the Leafs’ GF rate went virtually unchanged in the post-trade period.  It’s almost difficult to believe that a team could trade their then  top point-getter (Stajan), their then leading goal scorer (Hagman) and their 2nd leading point scorer among defencemen (White), yet suffer virtually no drop off in their offensive success rate  (source: NHL.com story).  They also traded Jason Blake who, when not skating eighteen laps around the offensive zone in the course of a seven-minute shift, then firing a 45 foot shoot into the precise geographic middle of the goaltender’s chest protector, occasionally seemed to rack up some points.

This last point screams out to me that the players the Leafs shipped out on the 31st were nothing truly special, just a bunch of guys who got points because they were there, the skating embodiment of the “replacement player” involved in GVT calculations.  I can’t support that hypothesis at this point with any hard data, but it sure looks like the points that those stiffs collected were the points that would be collected by whichever collection of stiffs the Leafs chose to throw over the boards (with apologies to Nicklas Hagman and Ian White for the “stiff” thing.  I liked you both).

Obviously, there are dangers involved in extrapolating full season numbers out of smaller data sets;  it’s exactly that process that every year has some idiot projecting that [insert random scrub here] “is on pace for a 164 goal season this year” as the highlights of his two-goal first game roll on TSN.   I understand the dangers of paying too much attention to data from small sample sizes.

In fact, that last point – small sample size – got me thinking about another possible explanation for the Leafs’ apparent improvement in the post-trade period, one that I hope to take a look at in the next post in this series.   Stay tuned.

Invitation: The 2009-2010 Maple Leafs End of Season Banquet

Look what I found lying around yesterday…

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March 25, 2010

Dear Valued Employee:

As a Toronto Maple Leaf player, you are invited to attend the annual Toronto Maple Leafs end-of-season banquet and awards ceremony.  This year, the banquet will be held on Saturday April 17th, 2010 at Jack Astor’s, unless of course we make the playoffs.  Ha ha, just kidding!  Seriously, though, the banquet is on the 17th at 7 p.m. sharp.

I’m not including a map to (or the address of) the specific Jack Astor’s restaurant we’re going to because it’s important that we keep the location of our team shindig confidential, to avoid having any unwanted guests.  In unrelated news, I’ve told Rickard Wallin (through a Swedish interpreter, he doesn’t read English) that we’ll be at Wendel Clark’s Classic Grille in Oakville.  He has been instructed to arrive early, demand to speak with the owner, and threaten him with trouble if we don’t enjoy our evening (which I have booked under the name “Fetisov”).  Don’t spoil the surprise for Ricky – remember how many stitches it took to close up the wound in Jason Blake’s face last year?  Oh, right, almost none of you were here for that.  Well trust me, it was good times.

The dinner menu at the actual, non-fake, banquet location includes: beef.  If you do not want to eat beef, or if you are a vegetarian or have other incorrect desires, let me just say that Edmonton gets pretty cold in the winter and – as incredible as it may sound – the Oilers are less likely than even us to win anything anytime soon. Jonas Gustavsson can have pickled herring, but only because he has a couple of doctor’s notes and I don’t like to get covered in exploding heart blood.  Remember, for this meal, the “Wellwood Rule” is in effect so portions will be limited to six servings of 48 oz. each.

After dinner of course, we’ll be handing out the end of season awards.  By tradition, your Master of Ceremonies will be the longest serving Leaf player, Tomas Kaberle.  As you know, also by tradition, the M.C. is ineligible to win any of the awards.  We offered to move Kabby out of that spot, but he insisted that he isn’t concerned about winning and wanted to stay (why does this sound familiar?);  in fact, he would like to MC both this year and next.  I can say that we’re prepared to meet him halfway on that one.

Awards to be presented this year include:

  • the David Williams Memorial “Mister Congeniality” Plaque (2010 recipient: Colton Orr – has anybody else noticed no one has disagreed with Colton about anything since he dummied Matt Carkner?);
  • the Wendel Clark “Most Valuable Player” Trophy (2010 recipient: Jeff Finger – shhh, don’t say anything, I’m talking trade with someone whose name rhymes with “Errol Flutter” and this MVP thing may get us Jarome Iginla and a pick); and
  • the Gary Leeman “Best Teammate” Prize (2010 recipient: former Leaf Vesa Toskala, in honour of the unremitting dedication to his craft he displayed.  He doesn’t know it yet, but Vesa will be in attendance at the Banquet courtesy of a burlap sack, some duct tape and the trunk of Jay Rosehill’s car.  Please note that this award will be presented posthumously and as soon as possible:  bring your own blunt object.)

After the awards ceremony, though it’ll be tough to top that last award, we’ll be moving to the entertainment portion of the evening.  Right now, the plan is for Phil Kessel, Nikolai Kulemin and Tyler Bozak to come up with something to dazzle us all. The rest of us will have to hope that’s enough.  So it’s pretty much business as usual.

Since he ought to contribute something to the team this year, Garnet Exelby will be responsible for bringing the beer.  When he screws that up, we’ll just buy some from the bar.  Please note that in view of the numerous unfortunate incidents resulting in so much broken glass at the goaltenders’ table last year, players are asked not to toss bottles to one another at any time.

Remember that while in attendance at this function, you are representing Maple Leaf Sports and Entertainment and the Toronto Maple Leafs.  Be pleasant and respectful to the wait staff, bartenders and busboys, especially Boyd Devereaux and Justin Pogge.

Stay as late as you like, and enjoy yourself.  Our next meeting as a team will be in Los Angeles on draft day.  Maybe we can go to the zoo or something, we’ll have plenty of time on our hands.

Yours truly,

fake brian burke signature

Setting the Market: Brian Burke and the NHL Trade Deadline 2009

Nb:  I am cross-posting this article to both my own site and Pension Plan Puppets;  I spent a lot of time working on this, and it occurred to me that if Jammies or Sexypants accidentally pushed the wrong “deletify” button over there at PPP, I might lose the whole thing.  So here ’tis:

Here’s the lowdown on the must-see command performance of the season:  Brian Burke goes to work at the trade deadline.

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Artist’s rendering:  Burke demonstrating how to do a proper hernia exam.

This year, for Leaf fans, there is one command performance that we are all waiting to see.  Strangely, the exhibition we’re awaiting will not be given by any skater dashing up the ice with stick and puck.  Rather, the demonstration of skill and excellence we await will be accomplished in an office using phone, fax and email.

Our angry Irish overlord is the only truly high-priced, blue-chip quality talent that we have in Maple Leaf blue and white this year.  In truth, everything that has happened with the players on the ice to date this NHL season is but prelude to that which is about to unfold before our eyes.  Burke’s handling of Pogge, his resolution of the Sundin situation, the acquisition of Brad May, the waivers of Stralman and Bell – all of these matters were mere preparation for the Bellicose One.

The eyes of Leaf Nation are upon Brian Burke at the trade deadline.

Jason Blake: When More is Less

Tonight, over at Pension Plan Puppets, in the Leafs/Bruins live game thread, mf37 posted some numbers about Jason Blake’s shooting percentage.  Essentially, the stats indicated that, between 2003 and 2007 (i.e. during his final seasons with the Islanders), Blake’s shooting percentage doubled (and in ’07 nearly tripled) over his then current career average.  Since joining the Leafs (and signing a hefty five-year contract – curse you, JFJ!) his shooting percentage has dropped to a number so low, you’d think it was expressing a person’s chance of getting hit by lightning while winning the lottery, being abducted by our alien overlords and riding a three-legged dog backwards to a nineteen length Triple Crown victory.

It got me thinking…

Observed phenomenon: Jason Blake takes a lot of shots from “the perimeter”, which is a polite way of saying that he was standing in the parking lot and unable to directly observe his intended target at the time of launching.

Known facts, and important (but blindingly obvious) inference to be drawn from them: NHL goalies (with the lamentable and all-too obvious exception of Andrew Raycroft) are not blind.  Most of them (again, except for Raycroft) have the ability to exert some amount of control over the movement of their extremities.  As a result, NHL goaltenders only infrequently whiff on shots taken from different continents.  Shooting from long distances is not, therefore, an effective strategy of scoring goals.

Statistical evidence:

This is what hockey-reference.com has to say about what Jason Blake has done in his career, in terms of offensive performance:

Season Team GP SOG/G S Pct. AVG TOI
1998-99 Los Angeles Kings 1 5 20 17:13
1999-00 Los Angeles Kings 64 2.05 3.8 11:17
2000-01 L.A./NY Islanders. 47 2.13 5 13:40
2001-02 New York Islanders 82 1.66 5.9 12:54
2002-03 New York Islanders 81 3.12 9.9 17:38
2003-04 New York Islanders 75 3.24 9.1 18:49
2005-06 New York Islanders 76 4 9.2 18:47
2006-07 New York Islanders 82 3.72 13.1 18:09
2007-08 Toronto Maple Leafs 82 4.05 4.5 17:49
2008-09 Toronto Maple Leafs 13 4.07 3.8 16:35
Career 3.08 8.1 16:22

Legend: GP = Games Played, SOG/G=Shots on Goal per game, S Pct.=Shooting Percentage, AVG TOI=Average time on ice.

Throw out the ’98-99 season (small sample size) and this year (small sample, incomplete data), and you’re left with 8 (more or less) complete seasons to consider.  Here’s what I noticed:  beginning in 2002, Blake’s average time on the ice per game goes way up – increasing by almost 40% from about 13 minutes a game in ’01/’02 to almost 18 minutes a game in ’02-’03.  Also in 2002, the goals start to bang home for Jason, as his shooting percentage jumps to 9.9%;  prior to that, Blake was lighting the lamp at something like a 4 to 6% clip.  Blake’s average ice time stays pretty steady, from then on, in the 18-19 minutes per game region.

Now look at what happens to his shots on goal per game.  That figure jumps from a career low 1.66 per game in  ’01-’02 to 3.12 per game the very next season – the same season his average icetime increases by 40% per game.

What the numbers show is that beginning in 2002/03, Blake was spending about 40% more time on the ice than he had before, but he began shooting the puck about twice as often as in the past.  That’s a lot of extra shots, proportionally, to fit into the extra ice time.  For a few years with the Islanders, it seems to have worked out because he was scoring goals roughly twice as often too, at the 9 – 13% clip.

Consider these numbers in the context of a hypothesis:  a tired skater is more likely to shoot the puck from a long distance. Rather than skate and drive towards the net, a fatigued player will – more often than not – elect to shoot from where he is when he receives the puck.

Blake is playing about just a bit less now than he did in his final years with the Islanders (the years of 9-13% shooting success).  He is shooting the puck about the same number of times, on average, if not a little bit more.  We have observed that – since he’s been in Toronto, anyway – he frequently shoots the puck from long distances.  It is unlikely that Blake was shooting from these distances while in Long Island;  it simply beggars belief that they’d be going in as frequently as they did for him;  it would take a major league marathon of sustained and repeated whiffage by a series of goaltenders, over a period of four years, for that to be true.   The key point is this – the long shots we’ve seen Blake take as a Leaf aren’t being taken in addition to the blasts he habitually took when he was an Islander.

Rather, I think the data suggest that Blake is currently replacing shots from closer in to the net  (i.e the quality shots he took as an Islander) with long distance bombs that have little or no chance of success.  One obvious explanation for that phenomenon is related to the “tired players take long shots” theory.  In short, the numbers suggest that  – now in his mid 30s, and with well-documented health concerns – Blake may well not be up to the challenge physically, and that fatigue or lack of conditioning is preventing him from scoring at the rate he previously did.

Discuss.  Am I missing something?