It's that time of the year again! No I don't mean the holidays. The 2010 NTRP ratings are out. Post your favorite examples of the most absurd rating outcomes you've come upon. No names/links/locations please! Just the stats. My hope is that the examples would shed light on some of the ways in which NTRP algorithm is broken. BTW, if you believe that it is NOT broken and want to argue this point, let's take that argument to another thread. I'd like to ask everyone to just post examples here, no opinions, and most certainly no info that could reveal the actual names behind the examples!
Post the most absurd 2010 NTRP rating examples - no names!
- Thread starter ian2
- Start date
OK a couple of examples I've run across...
Example 1:
2009 4.5C player match results:
4.5 singles: 26:3 win/loss. The three losses were in close matches to players who has similarly dominant records.
4.5 doubles: 1:0 win/loss.
Did not play any other matches.
2010 NTRP rating: unchanged, 4.5C
__________________
Example 2:
2009 3.5C player match results:
3.5 singles: 2 wins/6 losses. Both wins were competitive scores against the same 3.5 player with 0:9 win/loss ratio for the year. Two of the losses were 0 and 2, 0 and 0; remaining losses were competitive.
3.5 doubles: 8 wins/1 losses. The loss was 1 and 5. Best win was 0 and 2; the rest of the wins were competitive.
4.0 doubles: 0 wins/8 losses. Best loss was in split sets; worst loss 1 and 0; the rest of the losses averaged 2 and 3.
2010 NTRP rating: bumped up to 4.0C
Example 1:
2009 4.5C player match results:
4.5 singles: 26:3 win/loss. The three losses were in close matches to players who has similarly dominant records.
4.5 doubles: 1:0 win/loss.
Did not play any other matches.
2010 NTRP rating: unchanged, 4.5C
__________________
Example 2:
2009 3.5C player match results:
3.5 singles: 2 wins/6 losses. Both wins were competitive scores against the same 3.5 player with 0:9 win/loss ratio for the year. Two of the losses were 0 and 2, 0 and 0; remaining losses were competitive.
3.5 doubles: 8 wins/1 losses. The loss was 1 and 5. Best win was 0 and 2; the rest of the wins were competitive.
4.0 doubles: 0 wins/8 losses. Best loss was in split sets; worst loss 1 and 0; the rest of the losses averaged 2 and 3.
2010 NTRP rating: bumped up to 4.0C
This one is no mystery actually. 6:0 6:0 scores are thrown away because (get this!) DNTRP algorithm cannot (or would not) make a distinction between a default recorded as 0 and 0 and an actual match that was played.
I have hard on other threads that bagels don't count towards ratings at all.
The most I can contribute to this thread is that the number 1 ranked 3.5 guy in my state is still a 3.5 (A), dated 12/31/2009... not sure if he just didn't get updated or what.
Jim A
Professional
I think having an algorithm is fine because if it was up directly to Section Coordinators, etc then it would be even more of a mess.
A rating is a starting point to put together fairly competitive groupings on paper. Once you get on the court, it can all go to pot. We see it week in and week out, I can beat Player A but not Player B, however Player A owns Player B when they play.
You can cheat in any sport with enough thought. Some players will be bumped up too early, others held back for what appears to be no rhyme or reason. I've spoken about a couple people in my area who I have been surprised the past 2 years stayed at level.
If you lose 2 and 3 I wouldn't expect to be bumped down. Is David Ferrer getting dropped out of the ATP tour for losing the way he did last week?
The player you reference @ 3.5 appears to be more suited at dubs, so he won out at 3.5 dubs but lost most matches on average 5-6 games won @ 4.0 ....so he should go back to 3.5 where he can win out again? It would appear you lost a teammate
A rating is a starting point to put together fairly competitive groupings on paper. Once you get on the court, it can all go to pot. We see it week in and week out, I can beat Player A but not Player B, however Player A owns Player B when they play.
You can cheat in any sport with enough thought. Some players will be bumped up too early, others held back for what appears to be no rhyme or reason. I've spoken about a couple people in my area who I have been surprised the past 2 years stayed at level.
If you lose 2 and 3 I wouldn't expect to be bumped down. Is David Ferrer getting dropped out of the ATP tour for losing the way he did last week?
The player you reference @ 3.5 appears to be more suited at dubs, so he won out at 3.5 dubs but lost most matches on average 5-6 games won @ 4.0 ....so he should go back to 3.5 where he can win out again? It would appear you lost a teammate
#1 ranked 3.5 guy in my state got a new ranking... same as the old one, 3.5C. Ditto for #1 ranked 3.5 dubs team... they won all there was to win, and stayed 3.5.
njsigman
Rookie
I thought these results were absurd, but based on the other thread about playing up, it might answer some questions. This guy I know got bumped from 3.0 to 3.5.
0-8 combined on the season between 3.0 and 3.5 with these results
Score Match Type Level
6-4, 4-6, 4-3 #2 Doubles 3
6-0, 6-3 #3 Doubles 3.5
6-0, 6-1 #1 Doubles 3.5
6-2, 6-1 #1 Doubles 3
4-6, 6-3, 3-2 #2 Doubles 3.5
6-0, 6-1 #2 Doubles 3.5
7-6, 5-3 #3 Doubles 3.5
6-4, 6-2 #2 Doubles 3.5
0-8 combined on the season between 3.0 and 3.5 with these results
Score Match Type Level
6-4, 4-6, 4-3 #2 Doubles 3
6-0, 6-3 #3 Doubles 3.5
6-0, 6-1 #1 Doubles 3.5
6-2, 6-1 #1 Doubles 3
4-6, 6-3, 3-2 #2 Doubles 3.5
6-0, 6-1 #2 Doubles 3.5
7-6, 5-3 #3 Doubles 3.5
6-4, 6-2 #2 Doubles 3.5
Jim, having algorithm is fine indeed... except the fact that algorithm produces nonsensical results way too often. It's not about actual ability or match-ups, no algorithm could handle that. It's about the fact that given hard cold numbers, the algorithm generates garbage outcomes. Again, not always but in my opinion way too frequently.
Sorry, I lost you here. What do you mean?
There isn't a separate rating for dubs and singles. The guy's performance in 3.5 was a wash at best yet he was bumped up, unlike the guy in #1 example I gave. Compare their records and tell me whether it makes any sense... Neither guy is my teammate BTW although I do know them both.
This is no mystery. He played several competitive matches at 3.5. Unless all of those were against bottom of the barrel 3.5 players, he is going to get bumped.
What is "way too frequently"? The algorithm processes thousands and thousands of results and gets it right 95% or more. Can it be improved? Probably, but it's still not doing poorly over all.
Jim A
Professional
Ian, I think you and I are in the same section and general level of play.
If you are looking at tournament rankings, they don't match the league play. The top singles players in my district all moved up. there are some good ones who didn't and were likely on the bubble. I think in general the level in my area appears to be a bit below the national standard. The players who are winning still aren't at the next level.
Some of the players who have a lot of points from the tournament side aren't all that good. They just play every week and when there's a weak draw...find themselves in the semi's finals.
I used Ferrer as an example because he is the #8 ranked player in the world despite having weak results at the GS. He got thumped in the WTF against some of the top players, however would you say he isn't "competitive". Rating levels are much the same.
as for singles and doubles, since it combines it all together he went 10-7 last year at 3.5. with only 2 bad losses per the use of competitive being ~ 4 games..so 15/17matches were either competitive or won...when the computer looks at that how do you think it is viewed?
If you are looking at tournament rankings, they don't match the league play. The top singles players in my district all moved up. there are some good ones who didn't and were likely on the bubble. I think in general the level in my area appears to be a bit below the national standard. The players who are winning still aren't at the next level.
Some of the players who have a lot of points from the tournament side aren't all that good. They just play every week and when there's a weak draw...find themselves in the semi's finals.
I used Ferrer as an example because he is the #8 ranked player in the world despite having weak results at the GS. He got thumped in the WTF against some of the top players, however would you say he isn't "competitive". Rating levels are much the same.
as for singles and doubles, since it combines it all together he went 10-7 last year at 3.5. with only 2 bad losses per the use of competitive being ~ 4 games..so 15/17matches were either competitive or won...when the computer looks at that how do you think it is viewed?
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magmasilk
New User
reverse engineering
I think the esential missing piece in "reverse engineering" the ratings algorithm is the "computer rating/strength" of the opponent(s). Line number is a poor proxy.
Additionally, pretty sure Win-Loss doesn't directly matter (only games won). But not sure how many historical matches matches are considered. I would venture it would potentially looks back at more than a calander years worth of matches.
Overall, when I looked at a few rating bumps it seemed pretty consistent in that if you beat or played close someone who was bumped you most likely got bumped.
I think the esential missing piece in "reverse engineering" the ratings algorithm is the "computer rating/strength" of the opponent(s). Line number is a poor proxy.
Additionally, pretty sure Win-Loss doesn't directly matter (only games won). But not sure how many historical matches matches are considered. I would venture it would potentially looks back at more than a calander years worth of matches.
Overall, when I looked at a few rating bumps it seemed pretty consistent in that if you beat or played close someone who was bumped you most likely got bumped.
I'm not saying that the algorithm is not working in general. It works well in the middle of any given NTRP level. What I'm seeing though is than it starts wobbling at the margins and gets completely insane under certain scenarios. Can anyone seriously argue that the year-end ratings make sense for the two examples I have given? Especially when you look at these two examples side-by-side?
Yes we can explain how the algorithm arrives at these results (to a certain degree, given the fact that the system is intentionally opaque.) My point is, it arrives at some of these quite obviously absurd results because it can't handle certain scenarios. In other words, these are NOT the result intended by the designers of the algorithm; instead these are the product of the bugs in algorithm logic.
This thread was intended as a "catalog" of such bugs. To fix something that is broken it helps to understand how exactly it is broken. Not that USTA is necessarily looking to fix the algorithm problems. It appears that their priority lately had been to manipulate the algorithm application so that it would produce the desired "distribution" - which by the way is a valid approach to addressing some of the issues.
Yes we can explain how the algorithm arrives at these results (to a certain degree, given the fact that the system is intentionally opaque.) My point is, it arrives at some of these quite obviously absurd results because it can't handle certain scenarios. In other words, these are NOT the result intended by the designers of the algorithm; instead these are the product of the bugs in algorithm logic.
This thread was intended as a "catalog" of such bugs. To fix something that is broken it helps to understand how exactly it is broken. Not that USTA is necessarily looking to fix the algorithm problems. It appears that their priority lately had been to manipulate the algorithm application so that it would produce the desired "distribution" - which by the way is a valid approach to addressing some of the issues.
kylebarendrick
Professional
I'd say your two examples were both likely borderline. Example 2 is obvious - they played competitive matches while playing up so they got bumped. For example 1 you may be putting too much of an emphasis on W/L results. If the bulk of their wins were against mid-level players (or even some against 4.0s playing up) then I can understand why they weren't bumped.
I think you are right, though. It is at the boundaries between levels where the system struggles - especially with people playing at more than one level. As long as people don't try to manipulate the system, I can accept that it isn't perfect. None of us are going to be playing on the pro tour anytime soon.
I think you are right, though. It is at the boundaries between levels where the system struggles - especially with people playing at more than one level. As long as people don't try to manipulate the system, I can accept that it isn't perfect. None of us are going to be playing on the pro tour anytime soon.
Jim, we probably are in the same geographical section and general level of play, as you said... I got that impression from some of your posts in other threads.
I disagree somewhat with your point that "some of the players who have a lot of points from the tournament side aren't all that good." I mean, "that good" is a relative term
Sure, some of the best players at a given level do not play tournaments at all. However it's important to remember that only three best tournament results are counted. Bottom line is that top 10 ranked 3.5 players (which is my level though I'm not one of them ) are all pretty darn good as 3.5 goes. And the fact that both #1 singles and #1 doubles guys did not make it to 4.0 illustrates some of the problems I was talking about. Which by the way ties into that Ferrer example: imagine if the pros were rated on their game scores and who they played rather than on the match outcomes? I'm not saying that we amateurs should be ranked similarly to pros. But I am saying that not taking win/loss record into consideration (as one of the parameters, not the only parameter!) produces some of these nonsensical outcomes. And when computer looks at 27:3 at-level record with half of the wins complete blow-outs and the losses essentially ties, how do you think it is viewed? Again, do you see a modicum of consistency or common sense here? The 10-7 3.5 guy becomes 4.0; the 27-3 4.5 guy remains 4.5?
kyle, I don't see example 2 as obvious, not at all. The guy was borderline competitive at 4.0 dubs but at the same time he was less than competitive at 3.5 singles. The 3.5 dubs record was OK but not outstanding. Does this "obviously" equal a bump to 4.0? No, I don't think so. Remaining a 3.5 would appear to be a more "obvious" outcome.
The 4.5 guy with 27 - 3 record: half of his wins were from league play, so he obviously played 4.5 players there. Many of his wins were blow-outs. The rest were in tournaments. He might have played some 4.0 players along the way but he sure as hell beat some strong 4.5 players on his way to winning three of these tournaments... which earned him a very high state ranking. Given this info, do you still understand why he wasn't bumped to 5.0? I absolutely don't.
kylebarendrick
Professional
When I wrote "obvious", I meant that this is what likely happened. I think that the result that he got bumped up could have gone either way - and that is the risk of playing up. I agree that I'd have like to see the 4.5 get moved up. Do you know that tournaments are included in the ratings in your section? They aren't in all sections and how they are included is even more obscure than league results!
I'm not saying that the computer results for these guys was obvious - I am assuming that the both ended up close to the boundaries and agreed with your statement that the computer struggles with the boundary cases. I would like to see some weight given to W/L records since things like a 26-3 record do scream for a bump regardless of the scores!
I'm not saying that the computer results for these guys was obvious - I am assuming that the both ended up close to the boundaries and agreed with your statement that the computer struggles with the boundary cases. I would like to see some weight given to W/L records since things like a 26-3 record do scream for a bump regardless of the scores!
Jim A
Professional
Ian, here is all I can say about my experience with tournament/league play in my Section.
In '09 I played 3 events and won them all, beat everyone ranked ahead of me. My toughest matches were in league by far, lost more sets and games throughout the season.
I just took a look at the Tournament Rankings at my level. I've seen many of those guys play and while good 3.5's aren't a necessarily 4.0's.
The key to be ranked highly at the end of the year if you are a better than average 3.5 is to play a lot. If you view the results many of them play a ton of events and when the draw breaks their way, they cash in. Only needs to happen 2-3 times/yr and you are Top 10.
One of my teammates lost the majority of his league matches and knocked off one of the top ranked, and he was the better player on the court.
Many of the top league players don't play tournaments or if they do its only 1-2 per year and not enough to make a dent overall, they may only play State Open, etc....
No idea on the 27:3 guy, maybe he played a ton of people bumped this year, but since 5.0 is limited in many areas, I'm sure the computer is going to be certain before pushing someone to the last ledge of USTA play.
In '09 I played 3 events and won them all, beat everyone ranked ahead of me. My toughest matches were in league by far, lost more sets and games throughout the season.
I just took a look at the Tournament Rankings at my level. I've seen many of those guys play and while good 3.5's aren't a necessarily 4.0's.
The key to be ranked highly at the end of the year if you are a better than average 3.5 is to play a lot. If you view the results many of them play a ton of events and when the draw breaks their way, they cash in. Only needs to happen 2-3 times/yr and you are Top 10.
One of my teammates lost the majority of his league matches and knocked off one of the top ranked, and he was the better player on the court.
Many of the top league players don't play tournaments or if they do its only 1-2 per year and not enough to make a dent overall, they may only play State Open, etc....
No idea on the 27:3 guy, maybe he played a ton of people bumped this year, but since 5.0 is limited in many areas, I'm sure the computer is going to be certain before pushing someone to the last ledge of USTA play.
Um, it's because a crap load of 3.5s were bumped to 4.0. USTA is not as active in bumping 4.5s to 5.0. That's really the main flaw in what they've done the last 2 years. They didn't build up the 5.0 ranks. 4.5 is way diluted.
beststringer
Rookie
Someone 4.0 C, 0-5 record, got bumped to 4.5
dlk
Hall of Fame
I know that alot of people inflate their ability; with that said, I was typically the best player on the court when playing doubles. I could double bagel my partner 90% of the time.
I was a 3.0S (1st year in USTA) 2 total years tennis experience. Better than average athletic ability.
Mens3.5 record= 1-3
Mixed 6.5= 1-5
Mixed 6.0= 2-6
I was bumped up, and I'm a little confused, I wanted to play Mens 3.0, to see what I could do. I do think I could be competitive at 3.5, as was last year, and continue to improve.
I was a 3.0S (1st year in USTA) 2 total years tennis experience. Better than average athletic ability.
Mens3.5 record= 1-3
Mixed 6.5= 1-5
Mixed 6.0= 2-6
I was bumped up, and I'm a little confused, I wanted to play Mens 3.0, to see what I could do. I do think I could be competitive at 3.5, as was last year, and continue to improve.
I am confused that you are confused.
Why would you play up at 3.5 if you wanted to play 3.0??? The fact that you won a match at 3.5 says that you are 3.5. Why are you confused?
I still have yet to see any egregious rating examples. Most are just hyperventilating with no reason. If you have competitive (and THAT is the key word - COMPETITIVE - it doesn't matter if you lose, you just have to be competitive to get ranked up) matches at the higher level, that is where you are going to be ranked, it does not matter if you have a comparably horrible record in a lower level.
I'm having fun at the 4.0 level, though I'm 0-2 in first round tournament matches so far. Both matches were competitive, though, and I'm sure I'll break through at some point ha ha.
But looking at the winner of the last 4.0 tournament I played in, he played 9 matches in 2 tournaments, won them both, and only dropped 1 set.
So I don't have any illusions that I probably won't be winning any tourneys, but it's fun anyway and I've gotten a lot better in the last few months since i started focusing on match play.
But looking at the winner of the last 4.0 tournament I played in, he played 9 matches in 2 tournaments, won them both, and only dropped 1 set.
So I don't have any illusions that I probably won't be winning any tourneys, but it's fun anyway and I've gotten a lot better in the last few months since i started focusing on match play.
cknobman
Legend
I have a document (pre 2009) that goes into great detail on how the USTA dynamic rating system calculates your rating. Yes this is an official USTA document that was leaked to me from a friend.
Anytime you play up a level your dynamic rating is going to go up regardless of whether you win or loose (unelss you get double bageled) because your playing against players who are rated higher than you.
On the same note players playing against someone who is playing up are almost certainly have their rating go down whether they win or loose as well, because they are playing against lower rated players.
Most of the time when you see something whacky happen to a player when it comes to ratings you should look closer than just their flat out record of wins/losses. Look at who they played and what their rating was when they played that person.
A person could go 8-0 in a season but if every win they had was against players playing up a level then you will likely see that person get bumped down.
Likewise a person could go 0-8 and get bumped up if most of their matches were a level higher than what they are rated. Its simply that person plays higher rating makes that persons rating go up.
If you want an accurate rating then you need to make sure you play players rated the same as yourself, simple as that.
Anytime you play up a level your dynamic rating is going to go up regardless of whether you win or loose (unelss you get double bageled) because your playing against players who are rated higher than you.
On the same note players playing against someone who is playing up are almost certainly have their rating go down whether they win or loose as well, because they are playing against lower rated players.
Most of the time when you see something whacky happen to a player when it comes to ratings you should look closer than just their flat out record of wins/losses. Look at who they played and what their rating was when they played that person.
A person could go 8-0 in a season but if every win they had was against players playing up a level then you will likely see that person get bumped down.
Likewise a person could go 0-8 and get bumped up if most of their matches were a level higher than what they are rated. Its simply that person plays higher rating makes that persons rating go up.
If you want an accurate rating then you need to make sure you play players rated the same as yourself, simple as that.
I'd love to take a look at that document... could you possibly email it to me privately?
I absolutely agree with your statement (in bold). A different way to phrase it is "If you want an inflated rating you need to play up". Yet another way to express the same idea is "You performance playing at-level is disproportionately devalued as compared to performance of someone playing up".
People choose to play up, for a variety of reasons. There is nothing wrong with that. The wrong thing is that the algorithm cannot handle these situations. It demonstrably breaks down under such conditions and produces results that range from borderline "reasonable" to patently absurd.
What is wrong with the algorithm? If the player plays up and is competitive, then that person should play in that level. It is pretty simple. How does it "demonstrably breaks down"?
Jim, my experience playing league and tournaments this year was the opposite. Relatively easy going in leagues, much tougher competition in tournaments... could be just the lack of the draw. I still stand by my statement that highly ranked tournament players (top 10 for sure) represent the top range of a given NTRP level, regardless of the fact that some of the top players at a level do not play tournaments or play only a couple all year. As to the question of whether a top-10 3.5 is "4.0 material" - yes, absolutely, in the sense that these top 3.5s will beat bottom 25% of 4.0s 90% of the time and will beat lower 50% of 4.0s half of the time. Sorry about all the fractions
dlk
Hall of Fame
It was my first year playing USTA, didn't (and probably still don't) understand ratings. Played against a guy in WTT, who asked me if I wanted to play on his team; he said "you can always play up." I did not understand that this would bump me up. Thanks for the info, I believe I have a better understanding now.
Please take another look at the two examples I listed at the top of this thread. The only way you can interpret such outcomes is that the algorithm gives disproportionately higher weight to the "play-up" results. A players who is barely competitive at his own level gets bumped up due to simply playing up (losing all matches at the higher level, and losing convincingly except in one match). A player dominating his own level stays put. Also take a look at some of the examples other posters contributed. If such outcomes were "as designed", the design is flawed in my opinion. If they were not "as designed", the algorithm broke down...
OrangePower
Legend
0 & 0 scores do get thrown out, but not for the reason you suggest - defaults are indicated as such and it would be easy to exclude them from DNTRP consideration.
The reason the algorithm can't evaluate 0 & 0 scores is that it is the most lopsided score, and so the gap between the 2 players could range from very large to stupendously large, with no way to distinguish. For example, if I lose 0 and 0 to a pro, you could conclude that I'm no better than a 6.5 maybe, but you'd (and the rating algorithm) would have no way to deduce whether I'm a 2.5 or a 6.0.
The algorithm doesn't do well in these cases partly because of similar reasons to the 0 and 0 situation above. Another reason is that the algorithm relies on actual match scores, but actual match scores are not always a true indicator of difference in ability between players (but is all the algorithm has to go on).
For example, a 6-1 6-2 score is what we would expect if say a top 4.0 were to play a mid to low level 4.0. Now let's say the same top level 4.0 plays a top-level 3.5. In this case, we'd expect 0 & 0, or maybe 1 & 0. And if the top 4.0 is really trying, that's what we'd get.
But in reality, it's hard to keep that level of focus when you're clearly superior and have the match in hand. And also, the weaker player has nothing to lose and maybe 'goes for it' and has some luck. So you can see how the score could easily end up as 1 & 2... same as it would be for the top 4.0 versus the other 4.0. And the algorithm obviously can't distinguish.
There are several other ways to interpret such outcomes.
USTA weighs each match the same in terms of your dynamic rating. Every player has a dynamic rating and that rating changes- either a lot or a little- following every match.
Singles, doubles, playing in your level, playing up a level, etc. are all weighed the same. However, when you play singles or someone with a rating that is much higher or much lower than yours, your rating has the potential for greater change.
Let's use the example of Bill, an average 3.0 player. Bill starts the season with a 2.75 dynamic rating. Bill plays one of these 4 different matches with different opponents:
Bill d. Steve (3.0 with a 2.65 dynamic rating) 6-4 6-4
The computer expects close to this score, the match generates a 2.78 rating for Bill for this match, which gets averaged into his dynamic rating. Bill's dynamic rating goes up to 2.76
Albert (3.5 with a 3.45 dynamic rating) d. Bill 6-4 6-3
The computer expects a bigger differential based on their ratings, so Bill's rating for this match is 3.22. This gets averaged into Bill's dynamic rating, Bill has a new dynamic rating of 2.89. Albert gets a new dynamic rating of 3.40.
When you play doubles, essentially the change in the rating applied to the players is divided by 4 instead of dividing by 2. This means that you can change your rating more and get bumped faster in singles, but not that singles is weighted more heavily.
I played last year, went to state (won half of matches, the other half lost in tie-breakers). Was a finalist (one division) and a winner (other division) in a local Banana Open. Played all Fall at 3.5 and low 4.0 leagues- did well. And I got bumped down to 3.0!!!
My former team-mate played only for a year, did not go to state with us, then quit playing completely and got bumped up to 3.5.:shock:
My former team-mate played only for a year, did not go to state with us, then quit playing completely and got bumped up to 3.5.:shock:
Yes I see what you are saying about the gap potentially ranging from "very large to stupendously large". However the algorithm "knows" the DNTRP of each player beforehand. Why then the 6:0 6:0 scores between two 3.5 players are thrown out? Is it because there might "stupendously large" gap in ability? Nope. These scores are thrown out because throwing out ALL 6:0 6:0 scores is an easy thing to do. Lazy algorithm design basically.
Exactly, it cannot, and that's the problem. But it could, at least to a certain degree. It attempts to do this already, through the concept of "competitive score" (admittedly I don't know the exact details since the algorithm is kept secret). My feeling is that it could be "calibrated" much better for the "play up" scenarios, at least to the point of eliminating the most absurd outcomes.
Elisa, I understand that this is how the system works (a very good walk-through BTW). What I'm saying is that the way it works generates absurd results on the edges, i.e. in play-up situations. This happens, it appears, because the weighting is "off". The large differential in DNTRP between the two players results in the lower-rated player getting a disproportionally high DNTRP increase and the higher-rated player a disproportionally high DNTRP decrease. "Disproportionally high" as compared to the same scores between two players with closer "starting" DNTRP. A matter of calibration essentially. This compounds and in the end causes these strange outcomes. As I said a number of times through this thread: please take a look at the two examples I've given in the beginning. Yes these outcomes can be explained away. But do they make sense?
cknobman
Legend
Sure I can email it to you when I get home from work. Keep in mind though this is before they changed the algorithm last year so I dont know how much of it is still valid but the document outlines how it was done pre eoy 2009.
Awesome, thanks!
Jim A
Professional
We have very different experiences by far Ian2, interesting how it changes per person. Luckily we have the internet. Maybe we'll wind up facing one another next year!
In order to protect the innocent, I'll say that some of those top ranked players won only 3/7 of their tournament matches and about others hovered just a bit above .500. Quantity not quality, just review the matches on Tennislink and see who the wins/losses were against.
My teammate was 8-17 on the year and took one of them down and as stated earlier, he was the better player by far and it wasn't a fluke
The thing with 3.5 out here is the guy you play in the 1st round likely isn't that much different than the one who wins the tournament. There's a lot of parity once you get past the true beasts who have all moved up (and pretty much stayed to league play). If there are 20 people in the draw, 12-14 could realistically walk away with the beer mug
An average 4.0 is way different than some of the people we are discussing, especially in singles. When I play some of my buddies, its 6-3 on a good day and I have to really go for winners to stay in points, which is no way to play 4.0. They are more consistent, have better patterns and weapons. It takes a lot more to be successful from the move from 3.5 to 4.0 then from 3.0 to 3.5.
The people who played up in Twilight before the bump pretty much got rolled...so you definitely cannot just show up at 4.0 and win 50% of your matches because you were good at 3.5
In order to protect the innocent, I'll say that some of those top ranked players won only 3/7 of their tournament matches and about others hovered just a bit above .500. Quantity not quality, just review the matches on Tennislink and see who the wins/losses were against.
My teammate was 8-17 on the year and took one of them down and as stated earlier, he was the better player by far and it wasn't a fluke
The thing with 3.5 out here is the guy you play in the 1st round likely isn't that much different than the one who wins the tournament. There's a lot of parity once you get past the true beasts who have all moved up (and pretty much stayed to league play). If there are 20 people in the draw, 12-14 could realistically walk away with the beer mug
An average 4.0 is way different than some of the people we are discussing, especially in singles. When I play some of my buddies, its 6-3 on a good day and I have to really go for winners to stay in points, which is no way to play 4.0. They are more consistent, have better patterns and weapons. It takes a lot more to be successful from the move from 3.5 to 4.0 then from 3.0 to 3.5.
The people who played up in Twilight before the bump pretty much got rolled...so you definitely cannot just show up at 4.0 and win 50% of your matches because you were good at 3.5
I've got a news for you.
This is how every rating systems work! Golf, chess, even video games, you name it and they all weigh your best results more than your poorer ones in order to minimize the "gaming" of the system.
There is absolutely nothing "weird" about the examples you have provided.
A 3.5 guy gets killed in 3.5 singles, loses every match at 4.0 dubs (most of them badly), and is bumped to 4.0. A 4.5 guy absolutely kills it at 4.5 and is not bumped. Nothing weird about this, sure!
Jim, if you see a tall skinny mid-40s guy with blue Head bag, come over and say Hi... it could be yours truly
What you are saying about tournament play at 3.5 level is very much true. But the guys who consistently make it deep into the draws and end up in a top-10 spot at the end of the year are good as 3.5 goes...
As for "you definitely cannot just show up at 4.0 and win 50% of your matches": I tried to stay away from personal anecdotes but here is one: several of my teammates were swept into the 4.0 ranks in the big bump-up of 2009. They were all good 3.5s but not that good... only had slightly over .500 records playing league at-level that year. It's hypothetical but if they all had played a lot of tourneys that year (which they didn't) it's unlikely that any of them would have made it into the top 10 in the state. Here we are a year later. They all have .500+ record in 4.0 leagues. Their team made it to the districts where all these guys had very decent showing. On an even more personal note, my dubs partner and I (both 3.5) played several friendly doubles matches against two of these guys lately. It was always very close (and fun) but we won all of these matches... So maybe you can just show up at 4.0 as a strong 3.5 and win half of your matches.
Interesting... so you were bumped up at the end of 2009 even though you didn't play one USTA match that year? I see how that happened: you were on the bubble and once they added .10 (or whatever that wholesale bump-up figure was that year), you made it over. Once again, it's explainable but ridiculous... yet another example of the lazy programming by NTRP system folks.
Just why is it ridiculous? The USTA wanted to shift the boundaries between levels so people just below the boundary got bumped up. Why should someone escape that just because he has not played USTA for a year? His ability level is unlikely to have changed much.
I didn't give you my email... Here goes: ian2ten at gmail dot com. Thanks in advance!That's one way to look at it, and certainly a valid way. "Ridiculous" might have been too strong a word in this case. Another way to see this is that you "earn" your bump-up. If you were say a 4.0 in 2008 and did not play a match in 2009 you are still a 4.0, no matter what relative movement was applied to other people who did play... OK this is not one of the patently absurd examples, it's merely a questionable one.
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