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fe6250
11-16-2009, 10:20 AM
I searched the forum for this and didn't see it, so my apologies if this was answered somewhere already.

My question is simply this: What does it mean in the USTA NTRP guidelines where they refer to 50% of your rating coming from local league play and 50% coming from the benchmark calculation (assuming you are in post-season play)?

I understand the basic NTRP computation logic, but is the benchmark calculation anything more than doing the same thing relative to playoff performance or is there some other magic applied?

Thanks.

herrburgess
11-16-2009, 10:47 AM
I searched the forum for this and didn't see it, so my apologies if this was answered somewhere already.

My question is simply this: What does it mean in the USTA NTRP guidelines where they refer to 50% of your rating coming from local league play and 50% coming from the benchmark calculation (assuming you are in post-season play)?

I understand the basic NTRP computation logic, but is the benchmark calculation anything more than doing the same thing relative to playoff performance or is there some other magic applied?

Thanks.

The NTRP "expert" that spoke at our local league meeting said that the ratio was 70% local 30% benchmark (not 50-50). Basically they first take average of your dynamic NTRP rating over the course of the season; then they take the average NTRP rating of those players that made it to the States or Sectionals; finally they calculate your final year-end rating by weighing and averaging the two ratings using the 70:30 ratio. Make sense?

fe6250
11-16-2009, 10:58 AM
The NTRP "expert" that spoke at our local league meeting said that the ratio was 70% local 30% benchmark (not 50-50). Basically they first take average of your dynamic NTRP rating over the course of the season; then they take the average NTRP rating of those players that made it to the States or Sectionals; finally they calculate your final year-end rating by weighing and averaging the two ratings using the 70:30 ratio. Make sense?

Thanks - and it sort of makes sense. Whether it is 50/50 or 70/30, what I'm trying to figure out is how they calculate the benchmark part of it.

So for example - let's say I play 10 local league matches and 5 post season (state, sectional, etc..) matches. Would they take my NTRP generated from the local as 1 input, generate another from the 5 post season as another input and apply the 70/30 split to a new final rating? Or - is there more to it than that? Does my question make sense? Thanks!

raiden031
11-16-2009, 11:32 AM
The NTRP "expert" that spoke at our local league meeting said that the ratio was 70% local 30% benchmark (not 50-50). Basically they first take average of your dynamic NTRP rating over the course of the season; then they take the average NTRP rating of those players that made it to the States or Sectionals; finally they calculate your final year-end rating by weighing and averaging the two ratings using the 70:30 ratio. Make sense?

In trying to answer the OP's question...this makes little to no sense.

1) What is the difference in rating calculation between someone who DID and someone who DIDN'T play in post-season championship events?
2) How do they average your dynamic rating season over the course of a season with other players' ratings using a 70:30 ratio?

You see your response doesn't really answer anything other than that there is a 70/30 ratio somewhere.

The USTA has been too vague in answering this question, that I've not found a source that can really explain how ratings are calculated.

herrburgess
11-16-2009, 12:03 PM
1) What is the difference in rating calculation between someone who DID and someone who DIDN'T play in post-season championship events?
2) How do they average your dynamic rating season over the course of a season with other players' ratings using a 70:30 ratio?


Yea, I didn't think I was making much sense...trying again...

1) The only difference is that someone who played postseason has all of their postseason matches averaged into their dynamic rating, whereas someone who didn't play postseason doesn't. Since those people playing postseason are likely playing opponents with high(er) dynamic ratings, their ratings will likely be higher (win or lose).

2) When States and Sectionals conclude, the ratings of all the players who played postseason are averaged to create a benchmark rating; this is then averaged with each player's dynamic rating (both those that played postseason and those who didn't) on a 30:70 ratio. This is done so that all ratings across the section have a common basis. So they don't average it across the season, only at year end.

Confusing stuff...and I know I'm not doing the best job at explaining it, but I thought I'd give it a shot anyway.

Kick_It
11-16-2009, 12:03 PM
As far as I know, it's deliberately opaque; they don't want people to know how it is calculated.

There are pros and cons to that approach - one benefit being presumably less "gaming of the system" than currently exists.

fe6250
11-16-2009, 12:12 PM
As far as I know, it's deliberately opaque; they don't want people to know how it is calculated.

There are pros and cons to that approach - one benefit being presumably less "gaming of the system" than currently exists.

Well - it certainly appears that they are doing a good job of keeping it opaque! I appreciate the effort by everyone in trying to explain, but I fear that Kick_It is right and that the process is intentionally vague.

raiden031
11-16-2009, 12:14 PM
2) When States and Sectionals conclude, the ratings of all the players who played postseason are averaged to create a benchmark rating;


The ratings of all these players are averaged with what, each other? Are you saying there is exactly one benchmark rating that gets applied to everyone equally?


this is then averaged with each player's dynamic rating (both those that played postseason and those who didn't) on a 30:70 ratio.


I never looked at it like there is one single benchmark rating. I know Nationals is also factored in as well, so it goes all the way to the top. I was thinking more along the lines of each player who plays at a championship event has a rating that is determined differently then through DNTRP to calculate year-end ratings than if you only played in local league. In fact my understanding was that some players at Nationals have absolute ratings that are 100% determined by their play at Nationals, and not based on DNTRP. But kinda got stuck there due to lack of information and/or lots of false and misleading information.

herrburgess
11-16-2009, 12:23 PM
The ratings of all these players are averaged with what, each other? Are you saying there is exactly one benchmark rating that gets applied to everyone equally?

Yea, at least at the sectional level. It was explained to me that this is the only way they can ensure that a 3.5 in Birmingham is on a level with a 3.5 from Atlanta...

In fact my understanding was that some players at Nationals have absolute ratings that are 100% determined by their play at Nationals, and not based on DNTRP.

This may in fact be the case, as the "expert" only spoke about sectional ratings. Interesting stuff.

raiden031
11-16-2009, 12:40 PM
Yea, at least at the sectional level. It was explained to me that this is the only way they can ensure that a 3.5 in Birmingham is on a level with a 3.5 from Atlanta...



This may in fact be the case, as the "expert" only spoke about sectional ratings. Interesting stuff.

Here's some links I've looked up in the past that have led to alot of confusion I have about the system:

http://decaturtennis.com/genpage.cgi?S1=main_selections&S2=NTRPGuide
http://www.del.net/TENNIS/dynamic%20ntrp%20faqs.htm

I don't really know the history of NTRP, so its hard to say how old some of this information is and whether its just outdated, or just plain wrong.

herrburgess
11-16-2009, 01:19 PM
Here's some links I've looked up in the past that have led to alot of confusion I have about the system:

http://decaturtennis.com/genpage.cgi?S1=main_selections&S2=NTRPGuide
http://www.del.net/TENNIS/dynamic%20ntrp%20faqs.htm

I don't really know the history of NTRP, so its hard to say how old some of this information is and whether its just outdated, or just plain wrong.

The biggest thing I came away from the meeting with was the sense that they are more or less CONSTANTLY tweaking the way NTRP works.

amarone
11-16-2009, 06:28 PM
The NTRP "expert" that spoke at our local league meeting said that the ratio was 70% local 30% benchmark Other way round: 30% local, 70% benchmark - at least, according to the NTRP ratngs expert who spoke to our group. And I do not need to rely on memory - I have a copy of the presentation slides.

amarone
11-16-2009, 06:40 PM
I never looked at it like there is one single benchmark rating. I know Nationals is also factored in as well, so it goes all the way to the top. I was thinking more along the lines of each player who plays at a championship event has a rating that is determined differently then through DNTRP to calculate year-end ratings than if you only played in local league. In fact my understanding was that some players at Nationals have absolute ratings that are 100% determined by their play at Nationals, and not based on DNTRP. But kinda got stuck there due to lack of information and/or lots of false and misleading information. That is pretty much the way I understand it. The benchmark process starts at Nationals. The results at nationals are used to generate ratings of the players there - this recalibrates the section winners and helps even out possible discrepancies across sections. For example, if the players on the team from Southern averaged a 3.2 rating but comfortably beat SoCal, who averaged 3.4, that would suggest that a 3.2 in Southern is actually stronger than a 3.4 in SoCal. Hence the ratings are recalculated based on these national results, presumably resulting (in the above example) in Southern players having their ratings moved up and/or SoCal moved down.

Now the process can be repeated at Sectionals. The winners have had their ratings recalibrated at nationals, as just described. Now the ratings can be recalculated for all the teams at Sectional. They are recalculated based on the benchmark players who played at nationals. This now recalibrates across the winners of each District.

The process is now repeated by recalculating the ratings at the District championships, using the benchmark of the players on the team that won and went to Sectionals.

Then repeat at local level, using the benchmarks from District.

Hence the benchmark process riples down to attempt to recalibrate at every level to get more equality of rating levels all across the country.

Islandtennis
11-17-2009, 05:29 AM
Amarone,

Once again, you seem to have it right; both with the 70% Benchmark and how they are used