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Six months ago, my first ever column at Puck Prospectus introduced a topic near and dear to my heart: Attempting to come up with the best possible measure of players’ contributions to a hockey team. That article, “Plus/Minus – A Nonsense Stat?”, dealt with the deficiencies of that well-meaning but very flawed metric, hockey’s only mainstream measure of combined offensive and defensive contribution.
In recent years, there have been many outstanding efforts towards developing better statistics for hockey, many of them by Puck Prospectus authors, created both before and since the inception of Puck Prospectus. The best known of these, Tom Awad’s Goals Versus Threshold (GVT), provides an excellent measure of a players’ offensive, defensive, goaltending and shootout contributions over the course of a season. Importantly, the components of GVT are such that GVT can be applied over all of modern hockey history (when adjusting for annual goals per game rates), to evaluate players of different eras as well. GVT is a success: Not only is Puck Prospectus leaning heavily on GVT and it’s offspring, the predictive VUKOTA, but other publications are beginning to reference GVT as well.
Putting aside GVT, Gabriel Desjardins’ RATING, QUALCOMP and QUALTEAM metrics have advanced the cause of rate statistics. While seasonal stats–Goals, Assists, Points, +/-, PIM, GAA–have a familiar tangibility to them and while they intrinsically incorporate Will Carroll’s axiom “Health is a skill” over the course of a grueling season, it is rate statistics–GA/60, Net Penalties/60, Save Percentage–that even the playing field particularly of Time On Ice (TOI), providing a more equitable comparison between players.
The first steps of what I had in mind for developing that elusive “ultimate hockey stat” when I wrote “Plus/Minus – A Nonsense Stat” have been executed by Gabe in the aforementioned statistics, but the missing link for hockey sabermetricians has been adjusting accurately for the effects of the other players on the ice. With the assistance of the programming expertise of a good friend of mine, I’ve been able to harness enough computational horsepower to achieve the next big step in my vision. Say hello to ESTR.
Even Strength Total Rating (ESTR) is a more advanced version of Goal Difference per 60 minutes (GD/60), taking into account the quality of teammates and quality of opposition for all non-empty net Even Strength goals scored while a player is on the ice. ESTR is a sum of its components, Even Strength Offensive Rating (ESOR) and Even Strength Defensive Rating (ESDR), which are Goals For per 60 minutes (GF/60) above average and Goals Against per 60 minutes (GA/60) above average, when adjusted for teammates and opposition. To get ESTR and its components for each player, goal difficulties for all goals over the course of a regular season (or postseason) are calculated, weighted by the base GF/60 and GA/60 of the players on the ice. For each player’s GF and GA, the average goal difficulty the player was on-ice for is then applied against each player’s base GF/60 and GA/60 to get their ESOR, ESDR and ESTR.
In short, ESTR is the number of goals per 60 minutes of ESTOI that the player is worth at Even Strength, given NHL-average players as teammates and opposition.
As you know, it is suspect to draw conclusions from statistics with small sample sizes. While Nikita Filatov’s +3.53 ESTR in 54 minutes of Even Strength Time On Ice (ESTOI) and Ville Leino’s +2.68 in 147 minutes of ESTOI during the 2008-2009 regular season bode well for future success, the extreme rates are products of small sample size. Therefore, to illustrate only well-vested contributors, we’ll take a look at the 2008-9 regular season ESTR of players logging at least 500 minutes of ESTOI:
Even Strength Total Rating, Regular Season 2008-9
Rank Name Team Pos ESOR ESDR ESTR ESTOI
1 Patrik Berglund STL C +0.81 +1.21 +2.02 847
2 T.J. Oshie STL C +0.68 +0.87 +1.55 684
3 Tomas Holmstrom DET LW +0.74 +0.79 +1.53 612
4 Tim Connolly BUF C +1.50 +0.02 +1.52 631
5 Blake Wheeler BOS RW +1.05 +0.43 +1.48 925
6 Alex Tanguay MTL LW +1.26 +0.19 +1.46 599
7 Michael Ryder BOS RW +1.14 +0.31 +1.45 862
8 David Perron STL LW +0.57 +0.88 +1.45 915
9 Bobby Ryan ANA RW +1.48 -0.06 +1.43 814
10 David Krejci BOS C +0.70 +0.72 +1.42 1029
11 Travis Zajac NJD C +0.84 +0.57 +1.41 1081
12 Ruslan Fedotenko PIT LW +0.70 +0.70 +1.40 820
13 Stephen Weiss FLA C +0.83 +0.52 +1.35 1056
14 Alexander Semin WSH LW +1.20 +0.15 +1.35 850
15 Martin Havlat CHI RW +1.37 -0.06 +1.31 1151
16 Pavel Datsyuk DET C +1.25 +0.06 +1.31 1123
17 Zach Parise NJD LW +0.74 +0.52 +1.26 1192
18 Daniel Sedin VAN LW +0.80 +0.44 +1.23 1166
19 Marian Hossa DET RW +0.91 +0.31 +1.22 982
20 Rene Bourque CGY LW +1.05 +0.13 +1.18 721
Those of you familiar with Gabe’s work may recall that he rates Patrik Berglund highly as well. Check out the highlights of the 20 year old rookie’s goals at nhl.com: You’ll see a smart and skilled young player on offense, and that’s only looking at one side of the ice. The young Swede even logged more ESTOI than most of the top 10, giving much more confidence in his being able to sustain such performance in his sophomore season and beyond.
Aside from the trio of young Blues, the oft-injured Tim Connolly and Calgary’s Rene Bourque, the rest of the list is made up of many easily recognizable names, even to the casual hockey fan. Where are the Big Three, you might ask? Evgeni Malkin was close to cracking the list at +0.98 ESTR, but Sidney Crosby and Alexander Ovechkin do not rank as highly, due to negative ESDR.
You probably noticed that no defensemen made the top twenty overall. Would you believe that Dennis Wideman of the Bruins was last season’s top defenseman–not that Chara fellow–with +0.90 ESTR? Mike Green of the Caps, who turned in a gaudy offensive season, was second at +0.84 ESTR.
A quick note on Alex Tanguay, as it is current news: It’s surprising that a player of his talent–as illustrated by ESTR as well as conventional statistics–was not snatched up much earlier in free agency, until just this week. The former Montreal first liner could have made a great addition to a contending team. Instead, we will see how much Tanguay can help Tampa Bay in their long ascent up from the depths.
What’s next? Taking into account players’ contributions under man advantage situations, of course. Power Play Total Rating (PPTR) and Short Handed Total Rating (SHTR) are calculated similarly to ESTR, although with average GF not equal to average GA on the power play, some additional adjustments are involved. Overall Total Rating (OTR) is a weighted sum of ESTR, PPTR and SHTR, providing an overall value for each player, leaving only Net Penalty and shootout contributions to be considered in addition. More about them another time.
Timo Seppa runs the statistical hockey site www.icehockeymetrics.com.
Timo Seppa is an author of Hockey Prospectus.
You can contact Timo by clicking here or click here to see Timo's other articles.
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