HighSchoolHockeyForums.com

ghshockeyfan wrote:From a related thread:

http://www.ushsho.com/forums/viewtopic. ... ht=#605192

ghshockeyfan wrote:I'll be curious to see how KRACH computer ranking compares against some of the others mentioned here (Minnhock's PS2, USHSHO, MyHockeyRankings). KRACH is probably as "pure" as any algorithm in that it doesn't even care about score differential. That's why I prefer it. No additional human intervention.

Interestingly, it is supposed to give you odds on a game taking place. A team with a "10" rating value is considered the average team in the state regardless of Class designation. A team with, for example, a "100" rating is a 10:1 favorite over the average team. Similarly, you can compare any two teams based on their ratings.

SOS is just an average of opponents rankings played as of now.

Any computer ranking is worthless right now as many have said too limited data at this point.

http://www.ushsho.com/forums/viewtopic.php?t=29709

Most Recent Ranking Links:
==========================================
OVERALL:
http://www.bgoski.com/b/KRACH_OA.htm
CLASS AA:
http://www.bgoski.com/b/KRACH_AA.htm
CLASS A:
http://www.bgoski.com/b/KRACH_A.htm
SECTION:
http://www.bgoski.com/b/KRACH_SEC.htm
SOS (Strength-Of-Schedule) is at:
http://www.bgoski.com/b/KRACH_SOS.htm
==========================================

Added info. is at:
http://www.bgoski.com
And more info. on the girls forum at:
http://www.ushsho.com/forums/viewtopic.php?t=29597
http://www.ushsho.com/forums/viewtopic.php?t=27320

Here's the real details about KRACH:
http://www.mscs.dal.ca/~butler/krachexp.htm

And, our friends at USCHO speak to KRACH vs other options (yep, 7+ years ago):
http://www.uscho.com/2005/03/17/lets-get-kraching/

In addition to their ongoing rankings for both genders at both levels:
http://www.uscho.com/rankings/
http://www.uscho.com/rankings/krach/d-i-men/
http://www.uscho.com/rankings/krach/d-i-women/
http://www.uscho.com/rankings/krach/d-iii-men/
http://www.uscho.com/rankings/krach/d-ii-iii-men/
http://www.uscho.com/rankings/krach/d-iii-women/

Basic Explanation
KRACH — or “Ken’s Ratings for American College Hockey” — is the implementation for college hockey of a sophisticated mathematical model known as the Bradley-Terry rating system, first applied to college hockey by a statistician named Ken Butler.

This method is based on a statistical technique called logistic regression, in essence meaning that teams’ ratings are determined directly from their won-loss records against one another. A key feature of KRACH is that strength of schedule is calculated directly from the ratings themselves, meaning that KRACH, unlike many ratings (including RPI) cannot easily be distorted by teams with strong records against weak opposition.

The ratings are on an odds scale, so if Team A’s KRACH rating is three times as large as Team B’s, Team A would be expected to amass a winning percentage of .750 and Team B a winning percentage of .250 if it played each other enough times. The correct ratings are defined such that the "expected" winning percentage for a team in the games it’s already played is equal to its "actual" winning percentage.

An alternative definition of a team’s KRACH rating is as the product of its Winning Ratio (winning percentage divided by one minus winning percentage) with the weighted average of its opponents’ KRACH ratings. (The definition of the weighting factor makes this equivalent to the first definition of the KRACH ratings.) In addition to KRACH and RRWP, the table above lists each team’s Winning Percentage, Winning Ratio and Strength of Schedule (the aforementioned weighted average of their opponents’ KRACH ratings).


KRACH is provided for entertainment purposes only and is not used in any official way, nor is it endorsed by USCHO.com.

From the Hub:
http://www.mngirlshockeyhub.com/page/sh ... h-rankings
http://www.bgoski.com

About KRACH:
=================
KRACH is short for “Ken's Rating for American College Hockey.” Ken is Ken Butler, a statistician, and the mathematical model he used is known as the Bradley-Terry Rating System. The system and its details are well documented in great mathematical detail online (see KRACH explanation at Ken Butler's homepage).

..
The KRACH rating system is an attempt to combine the performance of each team with the strength of the opposition against which that performance was achieved, and to summarize the result as one number, a "rating", for each team. The higher the rating, the better the team.

This system accounts for strength-of-schedule (SOS) as it ranks the teams.

Teams with equal records and differing SOS can quickly be ranked as a result (i.e. team with stronger SOS is ranked higher than other teams with same record and weaker SOS).

The ratings are calculated purely from the game results (win, loss or tie), and do not use the goals scored at all. Overtime wins count as wins. Ties, for KRACH's purposes, count as half a win and half a loss.

KRACH only counts games against Minnesota State High School League opponents.
..

FASTWHEATIE wrote:I see you have Hibbing as 4-2-1 they are 5-2 on the season just wanted to let you know.

FASTWHEATIE wrote:I also see you have procter Hermentown as 3-0-1 I know Hibbing beat them 5-1 in Hermentown this season on November 20th

sinbin wrote:Still a few games to go, of course, but at the risk of jinxing either team, this is setting up nicely for the Tonka - Benilde showdown on 12/18. I wonder how much the winning team will benefit and the losing team will be penalized?

fishfreak11 wrote: does this ranking go by section win/loss or all games?

fishfreak11 wrote: Proctor/Hermantown is 5-1 in section play and Hibbing/Chisholm is 6-0 in section play (beating P/H 5-1)

P/H is ranked #1 with 90some and H/C is 12. or so

seems incorrect to me...

comments?

ghshockeyfan wrote:

FASTWHEATIE wrote:I see you have Hibbing as 4-2-1 they are 5-2 on the season just wanted to let you know.

FASTWHEATIE wrote:I also see you have procter Hermentown as 3-0-1 I know Hibbing beat them 5-1 in Hermentown this season on November 20th

THANKS! - I see this is entered as a 0-0 Tie on the Girls' Hub website... I assume someone from one of the teams will need to get that updated so that it is accurately reflected.

http://www.mngirlshockeyhub.com/game/sh ... rer=629051

hockeywild7 wrote:Hopkins, Lakeville South and Stillwater records are not correct on the rankings.

ghshockeyfan wrote:

hockeywild7 wrote:Hopkins, Lakeville South and Stillwater records are not correct on the rankings.

Thanks for noting this!

Hopkins has a win vs a non mn team so their krach record doesn't reflect that.

Lakeville South seemed to match when i just checked the hub vs krach.

Stillwater was a w short for krach, but maybe that didn't get entered until after the 11 am run of the rankings yesterday. I'll double check that later today.