## February 3, 2007

### Goaltender win statistic

Winning is the most important statistic for a goaltender in hockey. However, due to the fact that different teams win at different rates. Many teams could win with a terrible goaltender and the goaltender they use often gets a great win record (Cloutier, Theodore anyone). A great save percentage or GAA is worthless if it doesn't result in more wins. However you can calculate the likelihood of winning with a normal goaltender using a Pythagorean prediction: GF2/(GF2 + GA2), where GF = goaltender teams' scoring and GA = expected goals against. So if you score 3 and there are 2.8 expected goals against your goaltender: 32/(32 + 2.82) = 53%. If a goaltender looses a game when his team gets 7 goals for and there are the average 2.8 expected goals against: 72/(72 + 2.82) = 86%. Now if you sum up all those probabilities for any given goaltender then you get the number of expected wins. Then you just compare to the actual number of wins (I converted SOW/SOL to T and OTL to L). The difference between actual and expected gives you an idea how many extra wins a goalie is providing. However I wanted to scale out games played, so I divided by games played and multiplied by 60 (starting goaltender games per season), so that the W+ number represents the number of additional wins this goalie provides in the season where they play 60 games. A goalie like Luongo/Brodeur will play 70+ games so the numbers aren't perfect, but they're good enough.
W+ =60* (actual wins - expected wins)/GP
Here's the list [GP>10]:
 N lastname stat GP Actual Expected 1 HUET 7.91 33 19 15 2 GIGUERE 7.72 34 26 22 3 LUONGO 6.17 48 28 24 4 MASON 6.08 31 20 17 5 BRODEUR 4.63 50 31 27 6 EMERY 4.28 35 21 19 7 TURCO 3.50 44 24 21 8 HASEK 3.44 38 27 25 9 LEGACE 3.33 35 16 15 10 TOSKALA 3.17 29 21 20 11 NABOKOV 3.17 23 12 11 12 BACKSTROM 3.08 14 6 6 13 NORRENA 2.97 27 14 13 14 VOKOUN 2.56 22 14 14 15 LEHTONEN 2.50 45 22 20 16 FLEURY 2.28 41 23 22 17 TELLQVIST 1.76 16 8 8 18 KIPRUSOFF 1.57 46 26 25 19 BELFOUR 1.54 28 14 14 20 AEBISCHER 1.30 19 9 9 21 WARD 1.21 40 23 22 22 RAYCROFT 1.15 43 24 23 23 FERNANDEZ 0.77 39 19 18 24 MILLER 0.72 37 21 21 25 KHABIBULIN 0.54 36 18 18 26 JOSEPH 0.50 30 12 12 27 DIPIETRO 0.43 39 19 19 28 JOHNSON 0.28 14 5 5 29 BIRON 0.20 16 11 11 30 KOLZIG 0.10 38 18 18 31 THOMAS 0.08 38 18 18 32 LUNDQVIST -0.22 39 18 19 33 DUNHAM -0.25 12 4 4 34 HOLMQVIST -0.75 27 15 15 35 GRAHAME -0.79 14 5 5 36 ESCHE -1.01 14 5 6 37 BUDAJ -1.50 30 15 16 38 ROLOSON -1.61 44 20 22 39 TOIVONEN -1.90 11 3 3 40 SANFORD -3.68 11 3 4 41 LECLAIRE -4.53 20 6 8 42 GERBER -5.12 18 8 10 43 BRYZGALOV -6.12 14 6 7 44 THEODORE -6.28 21 8 11 45 GARON -6.33 18 8 10 46 AULD -6.44 25 8 11 47 Boucher -6.87 14 2 4 48 WEEKES -7.53 12 4 6 49 CLOUTIER -7.91 22 6 9 50 NIITTYMAKI -8.17 37 8 13 51 DENIS -8.82 26 10 14

It should be noted that luck plays a bigger part in these statistics as there aren't many events (<50), these results could be interpreted as random, however the list is a good representation of how man goaltenders on this list have played. I'll try going back a few season later on to see what happens when I include more data.