new metric

[david aka the TYZ]

https://sports.yahoo.com/ncaa-replaces-rpi-new-ncaa-tournament-selection-metric-154236270.html
NCAA replaces RPI with new March Madness selection metric


Just saw this. Very interesting and applies to about half our in season arguments. Curious to see this play out this year and in the future. Welcome to the term NET in all future rants on this board

 

[cincrulz11]

sounds worlds better than rpi. 10 point cap for win margin might be too low though.

 

[sedziobs]

This is a nice surprise. Looks like they're keeping the quadrant and team sheet system that was introduced last year. So we'll still have some basis for comparing resumes and projecting seeds.

 

[david aka the TYZ]

Yeah the 10 point cap seems low to me as well, but I do like the idea of it being capped. Not sure what a better cap would be. Maybe 20?

Wish they had more info on everything it factors in

 

[david aka the TYZ]

I will say if any team will be advantaged by a ten point cap it could be UC cause we don't seem to blow a lot of teams out we should. We'll beat a team by 13 that we coulda, shoulda, woulda beat by 30 more often than not it seems

 

[GarradJ21]

I wonder how this will affect the game itself. I mean a team has a ball up 8 and the other team decides not to foul since there’s only 5 seconds remaining. Does the team with the ball try to score?

 

[sedziobs]

you'll probably have fun with NET. i guess we'll get to see if its any better than RPI was.


ive read a few things about it i dont like, capping wins at 10 points, and the quality of your opponent doesn't matter for the stats you put up (holding duke to .98 ppp is the same as holding arkansas-pine bluff to .98ppp) but im not sure if thats actually true or people misinterpreting the data.


if it is true, it is probably a big benefit to us considering our schedule. rpi sucked but was actually great for us last year.

I thought it would be good to have a separate thread for NET.

The RPI is dead. The quadrant system remains, but NET will be used instead of RPI. The main improvements are the inclusion of tempo and scoring margin. The main drawback is the 10 pt margin cap, which seems too low to me. I think 15 would be better.

The algorithm components are different, but efficiency is still adjusted for opponents in the final result. So .98ppp vs AK-PB is the same as .98ppp vs Duke in terms of efficiency, but it is adjusted separately to account for schedule strength (opponent and location). Kenpom does the same thing. His rankings are based on adjusted efficiency, which start with raw efficiency. RPI didn't account for efficiency at all. Overall I think it's a huge improvement.

The biggest challenge this season will be in predicting what will happen to the NET rankings as the season progresses. Last year, we were able to use a variety of RPI forecasting tools that ran monte carlo simulations based on the simple RPI formula. Now we are sort of flying blind, and will be limited to analyzing the rankings in the present.

Cincinnati is currently ranked #46. It's way too early to be very meaningful. Unlike Kenpom, NET does not include any pre-season projections. RPI did not either. In another month we'll have a better idea of how good teams, and especially conferences, are.

 

[cincrulz11]

The algorithm components are different, but efficiency is still adjusted for opponents in the final result. So .98ppp vs AK-PB is the same as .98ppp vs Duke in terms of efficiency, but it is adjusted separately to account for schedule strength (opponent and location). Kenpom does the same thing. His rankings are based on adjusted efficiency, which start with raw efficiency. RPI didn't account for efficiency at all. Overall I think it's a huge improvement.

right but doesn't NET use 5 components to get your overall rating. so your game results factored in from strength of opponent is just 1 of the components. Then your raw efficiency, winning percentage, adjusted win percentage (adjusted for home, neutral, road), and scoring margin (capped at 10).



im not sure if each component is weighted the same or not. if they are all the same, that seems to benefit teams that beat up bad opponents.

 

[sedziobs]

right but doesn't NET use 5 components to get your overall rating. so your game results factored in from strength of opponent is just 1 of the components. Then your raw efficiency, winning percentage, adjusted win percentage (adjusted for home, neutral, road), and scoring margin (capped at 10).

im not sure if each component is weighted the same or not. if they are all the same, that seems to benefit teams that beat up bad opponents.

We don't know what the weights are, but they aren't all the same. They used a machine learning algorithm to develop a model that determined what weights gave the best hindcast results. Assuming it's properly calibrated, this would be an improvement over even Kenpom. I'm a little worried that it might be overfitted (meaning it predicts past results with past data really well, but not necessarily future ones - it could be overconfident that it can predict randomness). It's possible it will adjust the weightings in real time to correct itself.

 

[cincrulz11]

We don't know what the weights are, but they aren't all the same. They used a machine learning algorithm to develop a model that determined what weights gave the best hindcast results. Assuming it's properly calibrated, this would be an improvement over even Kenpom. I'm a little worried that it might be overfitted (meaning it predicts past results with past data really well, but not necessarily future ones - it could be overconfident that it can predict randomness). It's possible it will adjust the weightings in real time to correct itself.

well then that sounds much better than the ranting nate silver has been doing on twitter.

 

[sedziobs]

well then that sounds much better than the ranting nate silver has been doing on twitter.

I'm a huge fan of Silver's. I just finished his book, which is excellent. But I think he has the wrong idea here. The NET rankings are only meant to be definitive at the end of the season. They aren't like Kenpom, which is supposed to be as accurate as possible even right now. So judging rankings in November based on how good teams really are kind of misses the point. Similarly, no one would have used RPI in November as a legitimate ranking.

 

[sedziobs]

I'll add a more philosophical take. Silver and many others are complaining that NET is not as good as power rankings systems like those used in professional sports, or Kenpom and Massey in college basketball. This is true. Those systems will be better at forecasting what teams are better than others at any given moment. But a key difference is power ranking systems are NOT used to determine postseason qualification. So while they may be more accurate, there is nothing to be gained by achieving a better power ranking compared to actual record.

Competitive sports must maintain the idea that winning is the ultimate goal. Power rankings can help us to predict who will win, but the goal should always be winning in itself. Power rankings and Kenpom place no emphasis on actual wins. Winning by 10 points instead of 12 is the same as losing by 1 instead of winning by 1 (assuming pace and opponent are equal). If we're going to maintain the integrity of sports, winning by 1 must be proportionally more important than an extra 1 pt margin. NET is a good compromise of placing emphasis on both winning (like the RPI) and on efficiency (like Kenpom).

When people are disparaging the November NET rankings by saying "well Radford isn't that good because they lost to Duquesne", they are using a preconceived notion of how good Duquesne is. And based off of their record in past seasons, they're probably right. But NET only looks at this year's games. Duquesne is 4-1 with their only loss at Notre Dame (who's only loss is to Radford). They will probably end up being around average, but right now they have a strong record. When evaluating NET, it's important to view it as if you've never followed basketball at all - that you didn't have any idea whether Duke should be better than Radford. That's how NET sees the season, which is very different from power rankings.

 

[waterhead]

I'm a huge fan of Silver's. I just finished his book, which is excellent. But I think he has the wrong idea here. The NET rankings are only meant to be definitive at the end of the season. They aren't like Kenpom, which is supposed to be as accurate as possible even right now. So judging rankings in November based on how good teams really are kind of misses the point. Similarly, no one would have used RPI in November as a legitimate ranking.

Should be fun to track these things again this season and cross reference the NET with the other metrics to see if we can make any accurate predictions as to who will get the dance in and who won't.

 

[sedziobs]

Should be fun to track these things again this season and cross reference the NET with the other metrics to see if we can make any accurate predictions as to who will get the dance in and who won't.

Yes, it should be interesting. They're still using the quadrant system, so our opponents' NET rankings will be more important than our own. I hope to track the games of our potential Quadrant 1 and 2 opponents again later in the season.

 

[waterhead]

Yes, it should be interesting. They're still using the quadrant system, so our opponents' NET rankings will be more important than our own. I hope to track the games of our potential Quadrant 1 and 2 opponents again later in the season.

I have a feeling we are going to need some help with the quadrants. I don't see a lot of high end quality but hopefully we can squeak a few teams in quad 1 and 2.

 

[sedziobs]

Here's a preview of our potential Quadrant 1 and 2 games using Kenpom rankings.

Quadrant 1
Ohio St
@ Miss St
@ Houston
@ UCF

Quadrant 2
Ole Miss
@ UNLV
Xavier
UCLA
@ Tulsa
@ Wichita St
@ Temple
@ Memphis
UCF
@ UConn
@ SMU
Houston

That's 4 Q1 games and 12 Q2 games. Last year we played 9 Q1 games and 8 Q2 games. Temple, Wichita St, UConn and SMU are all between 80 and 87. If any of them end up in the top 75, it gives us another Quadrant 1 game.

 

[waterhead]

Here's a preview of our potential Quadrant 1 and 2 games using Kenpom rankings.

Quadrant 1
Ohio St
@ Miss St
@ Houston
@ UCF

Quadrant 2
Ole Miss
@ UNLV
Xavier
UCLA
@ Tulsa
@ Wichita St
@ Temple
@ Memphis
UCF
@ UConn
@ SMU
Houston

That's 4 Q1 games and 12 Q2 games. Last year we played 9 Q1 games and 8 Q2 games. Temple, Wichita St, UConn and SMU are all between 80 and 87. If any of them end up in the top 75, it gives us another Quadrant 1 game.

The countdown is on...lol! No better time than the present

Thanks for the breakdown

 

[sedziobs]

This week's rankings are out. Top 75 teams on our schedule:

20. Ohio St
28. Houston
32. Miss St
41. Cincinnati
42. UCLA
51. UConn
62. Xavier
64. UCF
71. Ole Miss
72. Temple

 

[Queens_NYC]

This week's rankings are out. Top 75 teams on our schedule:

20. Ohio St
28. Houston
32. Miss St
41. Cincinnati
42. UCLA
51. UConn
62. Xavier
64. UCF
71. Ole Miss
72. Temple

Surprised that Temple can be 7-1 with wins against Georgia as well as @St. Joe's and @Mizzou and still be ranked so low.

 

[sedziobs]

Surprised that Temple can be 7-1 with wins against Georgia as well as @St. Joe's and @Mizzou and still be ranked so low.

Those 3 teams are a combined 12-10. The rest of Temple's wins are over teams with losing records. Hopefully they can stay within 10 at Villanova.