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goblue78
01-20-2015, 08:28 PM
Or, at least it does for the first 31 places this week. The changes implemented last year make it very hard to overcome an RPI difference. If you're really confident in what the RPI does, it's alright, i guess, but it makes bracketology pretty boring.

Shirtless Guy
01-20-2015, 10:56 PM
You are correct, without the record vs TUC it requires a head to head matchup to overcome RPI.

Patman
01-20-2015, 11:15 PM
Or, at least it does for the first 31 places this week. The changes implemented last year make it very hard to overcome an RPI difference. If you're really confident in what the RPI does, it's alright, i guess, but it makes bracketology pretty boring.

I agree... but its only a matter of time until they find a reason to tweak it. Maybe by then I'll actually get off my butt and do something... probably not, but its a nice dream.

Red Cows
01-21-2015, 12:07 AM
I agree... but its only a matter of time until they find a reason to tweak it. Maybe by then I'll actually get off my butt and do something... probably not, but its a nice dream.

The tweak exists. KRACH:

http://www.collegehockeynews.com/news/2004/04/18_thelast.php

http://www.collegehockeynews.com/news/2003/02/27_nomore.php

http://www.collegehockeynews.com/info/?d=krach

Although Pairwise and KRACH do not look terribly different from one another at the moment.

Shirtless Guy
01-21-2015, 12:12 AM
The tweak exists. It's called KRACH:

http://www.collegehockeynews.com/news/2004/04/18_thelast.php

http://www.collegehockeynews.com/news/2003/02/27_nomore.php

http://www.collegehockeynews.com/info/?d=krach

Although Pairwise and KRACH do not look terribly different from one another at the moment.
True, KRACH is a much better way, I think someone used to publish a KRACH PWR but I can't find it. Not that it would change much like I said earlier, only way to jump a team now that there are only 3 criteria (RPI, Common Opp, head to head) is to beat them h2h which seems silly, not that we'd want it to be easy to leapfrog someone with a better RPI but it should be possible without playing head to head.

Red Cows
01-21-2015, 12:23 AM
In the top 16 in Pairwise, KRACH is currently the kindest to Denver, moving them up 3 notches, followed by Michigan Tech and Michigan, moving them both up 2 notches from their current Pairwise standing.

Conversely, it is unkindest to Vermont, moving them down 4 notches followed by Yale, moving them down 3 notches.

No matter what you think of Pairwise or KRACH, either is a far better system than what college football uses.

Polls are an utter joke. At least we all love a sport here where these are used for bragging rights, only.

RHamilton
01-21-2015, 01:33 AM
You can't really compare RPI before and after last year's change, since the way RPI is calculated changed significantly.

Rather than comparing the top 31 in PWR to current RPI, compare to the old-style RPI (the first column on USCHO's RPI table). There you'll see that the RPI adjustments (home/away weighting and QWB) have helped Duluth and hurt Miami.

TUC record has effectively been merged into RPI, and the cliff has been eliminated. The new PWR is more reliant on "RPI", but the notion of what RPI is has changed (for the better?). You can still "jump" a team through QWB -- it just happens to be added to RPI (and therefore counts toward the tie breaker for comparisons). I think most would agree that the elimination of the TUC cliff improves to overall ranking system, but sure, perhaps it makes it "pretty boring".

If all you're looking for is exciting comparison flipping, like the TUC cliff of old, KRACH sure isn't the answer. Embracing volatility seems a bit ridiculous.

FlagDUDE08
01-21-2015, 07:15 AM
Or, at least it does for the first 31 places this week. The changes implemented last year make it very hard to overcome an RPI difference. If you're really confident in what the RPI does, it's alright, i guess, but it makes bracketology pretty boring.

Didn't know our team had so much power. :D

dxmnkd316
01-21-2015, 08:04 AM
http://rpihockey.net/misc.rank1.shtml

Krach PWR.

Crimson on the Glass
01-21-2015, 08:47 AM
Well, which method most closely and consistently matches the criteria applied by the NCAA tournament committee at the end of the regular season to rank at large invitees? Surely that's what matters, is it not?

Patman
01-21-2015, 09:59 AM
The tweak exists. KRACH:

http://www.collegehockeynews.com/news/2004/04/18_thelast.php

http://www.collegehockeynews.com/news/2003/02/27_nomore.php

http://www.collegehockeynews.com/info/?d=krach

Although Pairwise and KRACH do not look terribly different from one another at the moment.

Please don't lecture to me :rolleyes:

FlagDUDE08
01-21-2015, 10:13 AM
Mandatory Eastern Bias post. :p:D

Of course they're not going to look that different, as many of the games that could have an effect are within the next month and a half. With the TUC cliff gone, there's certainly more of a dependency on my alma mater :p, but COp and H2H certainly have meaning.

5mn_Major
01-21-2015, 10:19 AM
The PWR and KRACH are notoriously different for women's D1. The WCHA is stacked and deep with talent (with every NC winner except that of 2014). So the WCHA SOS are off the charts, typically includes all of the top 5 or 6...and top rated teams in the east have SOS in the range of >10. So Wisconsin has only lost to Minnesota...and outside of that beating everyone else. This gives it the same record as BC (who has the best record). UW has a much tougher schedule than BC even if you take Minnesota out of the numbers. Yet, the PWR doesn't have them 1st (as having the best combination of quality wins), it doesn't have them 2nd (after Minnesota), it doesn't even have them 3rd...it has them 4th. That is 4th even though UW has the 2nd toughest schedule in the country and the team at 3rd has the 20th toughest schedule.

Many feel PWR penalizes SOS vs. KRACH.

goblue78
01-21-2015, 01:19 PM
You can't really compare RPI before and after last year's change, since the way RPI is calculated changed significantly.

Rather than comparing the top 31 in PWR to current RPI, compare to the old-style RPI (the first column on USCHO's RPI table). There you'll see that the RPI adjustments (home/away weighting and QWB) have helped Duluth and hurt Miami.

TUC record has effectively been merged into RPI, and the cliff has been eliminated. The new PWR is more reliant on "RPI", but the notion of what RPI is has changed (for the better?). You can still "jump" a team through QWB -- it just happens to be added to RPI (and therefore counts toward the tie breaker for comparisons). I think most would agree that the elimination of the TUC cliff improves to overall ranking system, but sure, perhaps it makes it "pretty boring".

If all you're looking for is exciting comparison flipping, like the TUC cliff of old, KRACH sure isn't the answer. Embracing volatility seems a bit ridiculous.

Those are good points, RHamilton, but (a) adding the QWB into RPI really is quite a bit different than having a "QWB measure" which counts as 1 point in the PWR. That leads to exactly the same sort of instability that TUC did, in which a tiny change in the status of team you beat flips a comparison. It's still possible through RPI, but the effect is continuous and therefore reduces volatility; and (b) Volatility isn't valued for its own sake. It's valued for creating genuine dependent paths for teams to get in which make the discrete outcome of discrete games so much more interesting at the end of the season. Those effects are now tiny, other than autobid effects. OK... maybe that *is* valuing volatility for its own sake.

Shirtless Guy
01-21-2015, 01:44 PM
Those are good points, RHamilton, but (a) adding the QWB into RPI really is quite a bit different than having a "QWB measure" which counts as 1 point in the PWR. That leads to exactly the same sort of instability that TUC did, in which a tiny change in the status of team you beat flips a comparison. It's still possible through RPI, but the effect is continuous and therefore reduces volatility; and (b) Volatility isn't valued for its own sake. It's valued for creating genuine dependent paths for teams to get in which make the discrete outcome of discrete games so much more interesting at the end of the season. Those effects are now tiny, other than autobid effects. OK... maybe that *is* valuing volatility for its own sake.

I think you are missing the importance of the QWB. The only reason UNO is ahead of BGSU is because of the QWB and that can be adjusted by results independent of those two teams. If a team like Denver falls back a bit and UNO no longer gets a QWB for sweeping Denver on Jan 9/10 they lose a 0.028 bump in RPI. Michigan Tech is only ahead of Vermont now because of Michigan continuing to improve and MTU getting a QWB for sweeping Michigan in October. The QWB is basically replacing the TUC cliff and softening it by giving more benefit to defeating difficult opponents, instead of treating every team above the cliff the same, there is wide variety.

There is a bonus of 0.06 to RPI for winning at Mankato (#1). There is a bonus of 0.002 to RPI for winning at home vs Quinnipiac (#20). There is no bonus for beating #21 and lower.

I don't think it is a whole lot different when you consider the adjusted RPI is the tiebreaker so its like getting a whole point for having the most QWB.

goblue78
01-21-2015, 03:17 PM
Not quite, Shirtless. Just to take an example, If you have, say, .002 QWB points and an opponent has none, this only switches the comparison when you're within 0.002 of each other, which is to say almost never. But if 0.002-0.000 QWB points gave you a full point, then that combined with, say Common Opponents will flip a comparison. So small differences in QWB between two teams mean almost nothing now, but would be huge in the TUC-like system. Of course, big QWB differences count just as you say. Yale is getting a whopping 0.0071 QWB points for four different wins and that is helping them a lot. But the higher your QWB, the harder it is for them to drop through a few odd results. As teams drop, the effects drop which is what eliminates the cliff.

Patman
01-21-2015, 03:26 PM
The PWR and KRACH are notoriously different for women's D1. The WCHA is stacked and deep with talent (with every NC winner except that of 2014). So the WCHA SOS are off the charts, typically includes all of the top 5 or 6...and top rated teams in the east have SOS in the range of >10. So Wisconsin has only lost to Minnesota...and outside of that beating everyone else. This gives it the same record as BC (who has the best record). UW has a much tougher schedule than BC even if you take Minnesota out of the numbers. Yet, the PWR doesn't have them 1st (as having the best combination of quality wins), it doesn't have them 2nd (after Minnesota), it doesn't even have them 3rd...it has them 4th. That is 4th even though UW has the 2nd toughest schedule in the country and the team at 3rd has the 20th toughest schedule.

Many feel PWR penalizes SOS vs. KRACH.

KRACH has the ability to differentiate between groups... to some extent. Any time when you have a game there is a winner and a loser... duh. But how do you reconcile that when you compare teams? Anything involving a win% or an average of win% then a game between two GOOD teams has to be a net loss. Likewise a game between two bad teams is a net win. Whereas, KRACH, if the collective performance is good enough the net effect of a game between two good teams leaves them relatively the same within realm of good teams... and same the other way.

This effect is real.

---

I think the decreased "schedule effect" induced by the broadening of out of conference opponents has helped reign this in... but if you want to still see in action... look at basketball RPI vs. computer systems.

Shirtless Guy
01-21-2015, 03:27 PM
Not quite, Shirtless. Just to take an example, If you have, say, .002 QWB points and an opponent has none, this only switches the comparison when you're within 0.002 of each other, which is to say almost never. But if 0.002-0.000 QWB points gave you a full point, then that combined with, say Common Opponents will flip a comparison. So small differences in QWB between two teams mean almost nothing now, but would be huge in the TUC-like system. Of course, big QWB differences count just as you say. Yale is getting a whopping 0.0071 QWB points for four different wins and that is helping them a lot. But the higher your QWB, the harder it is for them to drop through a few odd results. As teams drop, the effects drop which is what eliminates the cliff.It's all about softening the TUC cliff but still making wins over quality opponents mean something. I do wish there was a 4 component to allow jumping a team with a better adjusted RPI without playing H2H since the schedules are so insular and game locations matter. How do we compare MTU to UML? MTU wins the common opp, UML wins the RPI, UML wins the comparison on RPI tiebreaker...that seems very boring and overly simplistic. Without finding a way to jump UML in RPI it's impossible for MTU to pass UML. But at the same time, should MTU being 2-1 vs Michigan while UML is 0-1 be a huge determining factor? Probably not.

Shirtless Guy
01-21-2015, 03:32 PM
KRACH has the ability to differentiate between groups... to some extent. Any time when you have a game there is a winner and a loser... duh. But how do you reconcile that when you compare teams? Anything involving a win% or an average of win% then a game between two GOOD teams has to be a net loss. Likewise a game between two bad teams is a net win. Whereas, KRACH, if the collective performance is good enough the net effect of a game between two good teams leaves them relatively the same within realm of good teams... and same the other way.

This effect is real.

---

I think the decreased "schedule effect" induced by the broadening of out of conference opponents has helped reign this in... but if you want to still see in action... look at basketball RPI vs. computer systems.To be fair, there is still a rather large separation of east and west.

Michigan Tech has no common opponents with Harvard, Yale, Vermont, Merrimack, Providence, Colgate and Quinnipiac (I stopped after the top 20).
Mankato: BU, UML, Vermont, Providence, BC.
BGSU: BU, UML, Denver, BC

Red Cows
01-21-2015, 06:42 PM
Please don't lecture to me :rolleyes:

Mea culpa.

Was speaking, generally, and not to you specifically, although, that's what I actually did.