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06-06-2013, 08:01 PM
  #4
Micklebot
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Quote:
Originally Posted by eva unit zero View Post
Looking both at the numbers generated and at the way it is calculated, I have some definite questions about that.

Such as... why would the expected offense be TmGF20*LAGF20 and not TmGF20/LAGF20? That seems like a major flaw in the rating system. Obviously the same system when used defensively results in the same flaw.

For example, if the TmGF20 for Detroit is exactly 1.05, and the league average is 1.10, then the calculation projects expected offense of 1.155/20. Let's say Anaheim has a TmGF20 of 1.10, projecting to 1.00 (obviously). The next step in the calculation, which is 100*(PlayerGF20-ExpGF20)/ExpGF20, results in the following scores for two players with GF/20 of 1.50:

Detroit: 29.87
Anaheim: 33.33

So the player who plays for the better offensive team but doesn't individually have any more offensive success is scored as the better offensive player by a significant degree.
The expected Goals for per 20, or Corsi for or what ever base metric you're using is for a replacement player. So because you'd expect a player to score more, have a higher corsi or whatever on a better team (in regards to the relevant metric) they end up with a higher expected GF/20. You then compare their actual GF/20 to the expected value, and in the case of the Anaheim player he would meet the expected GF/20, but the Detroit player would exceed it and end up with a higher HARO: HARO(1st iteration) = 100*(GF20-ExpGF20) / ExpGF20)

Quote:
When any metric says that Dan Cleary is better offensively than Nicklas Lidstrom, Pavel Datsyuk, and Henrik Zetterberg... some serious questions need to be raised. Or that Justin Williams is the second-best offensive player with 162+ minutes.

It also ranks Scott Gomez top-40 offensively for the 2011-12 season, six spots ahead of Jason Spezza. Offensively.

So yeah, I can respect the effort... but it seems kind of flawed.
One thing to point out here is that it is measuring there effectiveness at generating corsi events, morso than how good they are offensively. I'm not a fan of all encompassing metrics as they often produce zany results, and the reason imo is that they aren't actually measuring what you or I think they are or what is intended to be measured. In this case, it seems to be attempting to measure the impact an individual has on his on ice CF%.


Last edited by Micklebot: 06-06-2013 at 08:08 PM.
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