NET Ranking for Tournament Selection

[nelsonmuntz]

I am fine with Ken Pom. I am less fine with the NET.

 

[navery12]

Up to 63 in the latest rankings

 

[ecasadoSBU]

My issue is with the NET calculation, and I don't think it makes sense to conflate NET and Ken Pom when they are separate.

The risk of allowing the Selection Committee to use 3+ different computer rankings is it won't take long to find one that has a 19-15 Syracuse team over a 25-7 UConn team. The Committee should use clearly defined criteria from understandable sources that results in objective assessments. The NET has features that are black box and others that seem to reward teams for a) playing a tough schedule even if that are losing to it, and b) beating up weak opponents in paycheck games.

The intention of the NET rankings is to make the process less transparent and steer at-large bids toward the top conference. The RPI was too easy for everyone to formulate and very difficult to unfairly leave teams out when they had good RPI numbers.

The NET allows them to maximize the amount of at-large bids that go to the Football 5 conference at the expense of good mid-major teams without having to be transparent in how they arrived at those NET rankings. Fortunately the Big East has been crashing the party and averaging 5 or more bids per year. That is good news for UConn

 

[nelsonmuntz]

The intention of the NET rankings is to make the process less transparent and steer at-large bids toward the top conference. The RPI was too easy for everyone to formulate and very difficult to unfairly leave teams out when they had good RPI numbers.

The NET allows them to maximize the amount of at-large bids that go to the Football 5 conference at the expense of good mid-major teams without having to be transparent in how they arrived at those NET rankings. Fortunately the Big East has been crashing the party and averaging 5 or more bids per year. That is good news for UConn

I agree with this assessment, with the added proviso that the Big East has a media partner with muscle in Fox Sports that wants to help the league. That matters a lot. ESPN never gave two scaleetos about the American.

 

[Glenn]

Zero love for RPI. It literally does not care who you beat. 3/4 of RPI is the win percentage of your opponents and 1/4 is your win percentage. The latter does NOT try to account for who you beat. It is a seriously stupid metric. So NET is better, though still not great.

 

[ecasadoSBU]

Zero love for RPI. It literally does not care who you beat. 3/4 of RPI is the win percentage of your opponents and 1/4 is your win percentage. The latter does NOT try to account for who you beat. It is a seriously stupid metric. So NET is better, though still not great.

It doesn't matter whether you loved it or not. It was far from perfect and it wasn't aiming to be perfect. There is no perfect way of choosing the best 68 (out of 250) teams into a tournament unless they all play a round-robin against each other.

But what the RPI did provide was that (1) it allowed everyone to calculate it easily (2) everyone knew what they needed to do to get a better index and make the tourney (3) and it was mostly transparent and fair to all members of all conferences

Now we lack all three on a new obscure ranking system that isn't perfect anyway and can be easily manipulated...

 

[Brochacho]

It doesn't matter whether you loved it or not. It was far from perfect and it wasn't aiming to be perfect. There is no perfect way of choosing the best 68 (out of 250) teams into a tournament unless they all play a round-robin against each other.

But what the RPI did provide was that (1) it allowed everyone to calculate it easily (2) everyone knew what they needed to do to get a better index and make the tourney (3) and it was mostly transparent and fair to all members of all conferences

Now we lack all three on a new obscure ranking system that isn't perfect anyway and can be easily manipulated...

If its not easily calculated and teams don't know how to get a better rating how is it easy to manipulate?

 

[ecasadoSBU]

If its not easily calculated and teams don't know how to get a better rating how is it easy to manipulate?

Because now its in the hands of the NCAA to play nice. Do you trust the NCAA? I don't!

I prefer if the formula is readily available for everyone. That everyone can use the formula to improve their rating as opposed to just having the NCAA gives us weekly NET ratings that we have no idea how they were calculated.

A monopoly on access/information is never a good idea

 

[MU in MKE]

Presumably, if the algorithm for the NET is not fully revealed, the NET is more difficult to manipulate (unlike the RPI). That means the NET can do what it is meant to do, measure the quality of the teams, without being meddled with in scheduling or during games.

I watched the NET very closely last year, and while not perfect (I have my own gripes, such as rewarding teams that play at a very slow pace, aka B10 teams), it is a far superior metric. The reason Kenpom is used as an example so often when talking about the NET is because KP was the closest system the NET replicated.

Some of the criticisms here are just a product of it being too early to judge the NET (you will see a lot of wild swings at this point in the season) and the rest is just misunderstanding. For example, feasting on cupcakes won't have the desired outcome you want unless you REALLY beat up on them. If you want to move up when playing cupcakes, the margin of victory you need will vary depending on how bad the opponent is. A 175 cupcake vs a 250 vs low 300's team will need an increasingly large margin or you could actually see your NET drop. I saw this a lot last year when we (Marquette) beat 300+ NET teams by a wide margin but our NET rating went down.

 

[BlueMAB]

If its not easily calculated and teams don't know how to get a better rating how is it easy to manipulate?

I think he's saying its easily manipulated by the NCAA, not the teams; because only the NCAA knows what the calculations are.

 

[ecasadoSBU]

Presumably, if the algorithm for the NET is not fully revealed, the NET is more difficult to manipulate (unlike the RPI). That means the NET can do what it is meant to do, measure the quality of the teams, without being meddled with in scheduling or during games.

I watched the NET very closely last year, and while not perfect (I have my own gripes, such as rewarding teams that play at a very slow pace, aka B10 teams), it is a far superior metric. The reason Kenpom is used as an example so often when talking about the NET is because KP was the closest system the NET replicated.

Some of the criticisms here are just a product of it being too early to judge the NET (you will see a lot of wild swings at this point in the season) and the rest is just misunderstanding. For example, feasting on cupcakes won't have the desired outcome you want unless you REALLY beat up on them. If you want to move up when playing cupcakes, the margin of victory you need will vary depending on how bad the opponent is. A 175 cupcake vs a 250 vs low 300's team will need an increasingly large margin or you could actually see your NET drop. I saw this a lot last year when we (Marquette) beat 300+ NET teams by a wide margin but our NET rating went down.

if the 300+ Division-I programs + fans + media know the formula and everyone attempts to manipulate the effect is minimized. We all know that what is equal is not an advantage. This applies in sports and in non-sports context. If everyone cheats then there is little gain. It's only when a few cheat and everyone is held to the rules that the cheater benefits!

In this case when only the NCAA knows the formula how do we know that they are being honest? How do we know they aren't using it to bump up their favorite F5 program at the expense of everyone else? How do we know that the NCAA didn't provide the formula to a few programs so they can take advantage at the expense of everyone else?

Again, I do not trust the NCAA and you shouldn't either. The NCAA is a sanctioning body that has given too much power to a few schools and I can easily see them using this obscure NET to benefit those same power program. Why? Because the NCAA gets more revenue when a big time program is playing whether from ticket sales or TV revenue

 

[MU in MKE]

if the 300+ Division-I programs + fans + media know the formula and everyone attempts to manipulate the effect is minimized. We all know that what is equal is not an advantage. This applies in sports and in non-sports context. If everyone cheats then there is little gain. It's only when a few cheat and everyone is held to the rules that the cheater benefits!

In this case when only the NCAA knows the formula how do we know that they are being honest? How do we know they aren't using it to bump up their favorite F5 program at the expense of everyone else? How do we know that the NCAA didn't provide the formula to a few programs so they can take advantage at the expense of everyone else?

Again, I do not trust the NCAA and you shouldn't either. The NCAA is a sanctioning body that has given too much power to a few schools and I can easily see them using this obscure NET to benefit those same power program. Why? Because the NCAA gets more revenue when a big time program is playing whether from ticket sales or TV revenue

It is difficult to argue against a conspiracy theory. At the end of the day, the NCAA is just an organization made up of member schools. If schools didn't trust the NCAA, they need to clean house themselves. However, since the NET follows multiple analytical models such as Kenpom, I think it is pretty clear that the outcome is decently satisfactory for most people.

Besides, NET by itself does not determine who makes the tournament. It is only one tool used to evaluate the field. Because of this, and because we can ultimately see who makes it or not, an individual can make up their own mind in March whether things are equitable or not.

 

[nelsonmuntz]

I can't believe anyone is arguing that teams shouldn't know what goes into a metric that is critical for determining access to and seeding within the NCAA Tournament. This is like arguing an employee should not know in advance what factors will go into his performance review.

 

[Martin]

I appreciate everyone’s well thought and written responses. It’s helpful in trying to understand it better. At the end of the day it is the corrupt NCAA using it. Maybe there should be a corrupt NCAA factor added to it as well.

 

[navery12]

I can't believe anyone is arguing that teams shouldn't know what goes into a metric that is critical for determining access to and seeding within the NCAA Tournament. This is like arguing an employee should not know in advance what factors will go into his performance review.

When it eliminates teams trying to game the system and end up with an arbitrary high ranking, yes that's a good thing

 

[auror]

I can't believe anyone is arguing that teams shouldn't know what goes into a metric that is critical for determining access to and seeding within the NCAA Tournament. This is like arguing an employee should not know in advance what factors will go into his performance review.

The factors are public knowledge. Just the weights are secret.

Wins, winning percentage, scoring margin, strength of schedule, efficiency.

 

[Waquoit]

When it eliminates teams trying to game the system and end up with an arbitrary high ranking, yes that's a good thing

Is that a true threat or just cover for the lack of transparency?

 

[navery12]

Is that a true threat or just cover for the lack of transparency?

The threat of teams gaming the system? Yes it happened every year with RPI

 

[Waquoit]

The threat of teams gaming the system? Yes it happened every year with RPI

I don't get into the weeds with this stuff but did this "gaming" really manifest itself in many undeserving teams getting in?

 

[navery12]

I don't get into the weeds with this stuff but did this "gaming" really manifest itself many of undeserving teams getting in?

Realistically we're talking about like 2-3 bubble teams a year so not really

 

[auror]

I don't get into the weeds with this stuff but did this "gaming" really manifest itself many of undeserving teams getting in?

https://www.washingtonpost.com/archive/sports/2006/03/05/the-numbers-gamed-span-classbankheadmissouri-valley-conference-teams-have-used-savvy-scheduling-to-boost-their-rpi-and-possibly-burst-the-bubble-hopes-of-some-major-programsspan/ccf24201-fb81-4dcf-b44f-d2ae3d09969a/

They ended up getting 4 bids instead of the 6 that were in the RPI top 45, which is about as many as they deserved. But there's quotes from the actual conference that they withheld NCAA $ distributions if teams didn't schedule properly to game the system.

 

[ToolzieFan]

Ultimately, any objective ranking system should put the best teams in the tournament. If a system is doing a good job of placing the best teams in the tournament, then it should be a fairly accurate predictor of who will win games. The RPI was not the most effective tool at predicting tournament success; therefore, I'm open to a new system like NET that incorporates offensive and defensive efficiency. My quick Google search hasn't found data on the performance of NET rankings last year, but here is an article demonstrating that RPI was a worse predictor of tournament performance than preseason rankings from 2002-2017.

Want To Know Who Will Win During March Madness? Go Back To The Preseason Polls.

Data is king. When we’re making any decision of consequence about the future — whether in business, sports or politics — our tech-filled world demands that we…

fivethirtyeight.com

 

[ToolzieFan]

More evidence the RPI wasn't the best option. I'd trade some level of transparency for a better system. I'm sure NET isn't perfect. I think it's probably an upgrade, though.

The RPI is Not the Real Predictive Indicator

Despite taking quite the beating recently, the Ratings Percentage Index (RPI) is still the official and favored ranking system of the NCAA Men’s Basketball Selection Committee. The RPI does n…

harvardsportsanalysis.wordpress.com

 

[SubbaBub]

Record vs top teams - Top 25
Record vs tournament level teams - Top 50
Record vs at large bubble teams - Top 100

Losses vs everyone else

That's all that should really matter. Even a mid major should have a winning record vs Top 100 teams and enough of a sample for it to mean something. Sure, Duke gets more Top 25 games but if they go 1-5 in those games then you can determine they aren't that good compared to a team that goes 2-1.

Conversely, a mid major that goes 0-1, better have a superior record agaisnt the Top 100.

This shouldn't be this hard.

 

[HooperScooper]

Record vs top teams - Top 25
Record vs tournament level teams - Top 50
Record vs at large bubble teams - Top 100

Losses vs everyone else

That's all that should really matter. Even a mid major should have a winning record vs Top 100 teams and enough of a sample for it to mean something. Sure, Duke gets more Top 25 games but if they go 1-5 in those games then you can determine they aren't that good compared to a team that goes 2-1.

Conversely, a mid major that goes 0-1, better have a superior record agaisnt the Top 100.

This shouldn't be this hard.

I guess the question then is what metric do you use to rank the teams that a team played? If you're going to use a record against top 25, top 50 and top 100 then you need a good way to rank every team. Sort of a circular calculation though.