Monday, December 23, 2013

A Christmas gift to Northwest Washington - Full year-end Estimated Dynamic NTRP ratings list

I have just updated the Estimated Dynamic NTRP Rating list for Northwest Washington in the Pacific Northwest section of the USTA here.

As always, if you want more detail on how your rating was arrived at, an Estimated Dynamic NTRP Rating Report is the best way.  Contact me for more details.

Saturday, December 21, 2013

The perfect stocking stuffer - Estimated Dynamic NTRP Rating Reports are on sale

It is four days before Christmas and if you are still looking for a stocking stuffer for the tennis nut in your family or group of friends, I have a great one for you.

Tennis players that play in USTA leagues tend to obsess about their NTRP rating.  Year-end ratings came out earlier this month and many are wondering why they were/weren't bumped up/down.  A great way to find out is to get an Estimated Dynamic NTRP Rating report.  A report will show each match they played in a relevant USTA league, how it was individually rated, and how it affected their dynamic rating.  It will also show what their estimated year-end rating was and offer an explanation for why it ended up where it did.  See another example in this earlier blog post.

Thru Christmas, I'm offering 25% off all reports.  Contact me for more information or to order a report.

Tuesday, December 17, 2013

The 2014 USTA League season is upon us, Estimated Dynamic NTRP Reports are already being generated

It has been just two weeks since 2013 year-end NTRP ratings were published by the USTA, and people are already interested in what their 2014 dynamic rating is looking like.  This is because 2013 Fall leagues and/or 2014 early start leagues have had matches since the 2013 league year ended (10/27) and these matches will count towards the 2014 ratings.  In some cases players have played 5, 10, or more matches in "2014" already.

Given this, I've started generating Estimated Dynamic NTRP Rating reports for 2014 already and can do so for any USTA League player from any section.  Some are even signing up for periodic updates of their report and getting a discount over buying them individually which is a great way to track progress towards any goals that may have been set.

See the link above or contact me if you are interested or have any questions.

Sunday, December 15, 2013

USTA League Points Per Position Survey - Probably not as good an idea as it appears on the surface

The USTA sent out a survey last week asking for people's thoughts on a "Points Per Position" scoring proposal for USTA League team matches.

The short summary on the proposal is that rather than each court counting equally and there being a winning team based on who won the most courts in a match, the lower numbered courts will have more points allocated to them and team standings would be based on total points accumulated rather than team wins/losses.  The idea is that by doing this, teams will be encouraged to play their best players on the courts that are worth more points resulting in more consistently competitive matches.

Apparently, the USTA has received complaints from players about uncompetitive matches and/or "stacking".  What happens with stacking is that a team tries to steal a team win by playing weaker players on court 1 in order to try to assure that they get wins on courts 2 and 3.  In a normal 5 court match, by throwing courts 1 and winning courts 2 and 3, the team can get a 3-2 team win.

This is great unless you are the good player on the team playing things straight up.  You may be a strong 4.0 and have to face a so-so 3.5 playing up on court 1.  This isn't a competitive match and not a lot of fun for either player.  It can also wreak havoc with ratings as having players that are rated far apart play each other is hard to properly rate.

The issue originates in the misconception that there is meaning to the court number, e.g. court 1 is supposed to have the best player(s) and higher numbered courts are supposed to have the weaker players.  The USTA actually states that court numbers don't carry that meaning, they could just as easily be name red, white, and blue.  If there is no meaning to the court number, players shouldn't expect to play court 1 and get a tough opponent.  You might or might not.

But let's humor the USTA and consider what happens with a Points Per Position scoring system.

Given that some courts will be worth more, this results in two things.

First, there is even more pressure on captains to get the ringers and stud players that they can play on court 1 and be reasonably assured of a win.  There are already complaints about teams that recruit players to self-rate too low or manipulate ratings to get bumped down so they can be a ringer, and the pressure to do so would be even greater with this scoring system.

Second, the higher numbered courts will be worth less, effectively telling the weaker players on the team that they are less important.  One can do the math and see how a team might just have studs that always win courts 1 and could accumulate enough points that it doesn't matter if they ever win courts 2 or 3.  This effectively means teams don't need depth.

And if the original issue was uncompetitive matches, the problem may still not be solved.  Consider a team that has several exceptional players for their level.  Their opposition will probably know this and if they have several very good players that are still going to be underdogs, the prudent move may still be to play these players on the higher numbered courts rather than wasting your best players in losses on court 1.

If this is the case, we just changed the system to one that rewards top-heavy rosters and sandbagging and didn't in fact help reduce the stacking that was the original complaint.

So while I understand what they are trying to do, I don't think this is the right approach.

There are other approaches that might be better solutions.

First, while the USTA says the court number doesn't matter, it actually does a bit.  If there are defaults, they start at the highest numbered court, so there is some meaning to the courts today and you wouldn't want to put your best doubles team on court 3 only to have the other team default that court and your best players don't get to play.

An extension of this that gives a little more meaning to the courts would be to have a rule that players playing up are not allowed to play on a lowered number court than players at level.  This would avoid the scenario where a team throws a court by playing their player playing up on court 1 and avoid the biggest case of uncompetitive matches.

Another that the USTA will never do is to publish actual dynamic ratings and requiring that a team have their highest rated players on the lower numbered courts.  Or if they don't want to publish the ratings, have an app that lets you put in your line-up and it tells you which court the players must be on to have the right ordering.

Now, both of these would essentially ensure that the stronger team/line-up usually wins.  We'd be taking away the ability of a captain to manage their team into the best position to get the 3-2 win.  If the USTA wants to take the drama out of some of the matches and reduce the upsets, either of these could work.

What do you think?  Leave a comment and let me know.

Monday, December 9, 2013

Tips to help improve your USTA NTRP rating

The USTA NTRP year-end ratings are out and 2014 leagues will be starting soon if they haven't already.  Some players have been bumped up achieving what was perhaps a goal for 2013, but others with that same goal didn't quite make it.  Whatever the case may be, if your goal for 2014 is to move up a level, here are some tips on how to accomplish that.

First, the way the NTRP algorithm works, every game counts.  Winning a match 6-2,6-2 is going to do more to improve your rating than winning 6-4,6-4.  It is the couple of games here and there that get away, especially when playing lower rated opponents, that is the difference between the players that get moved up and those that don't.

But it doesn't just matter when you win.  We like to remember the good matches and ask how we didn't get moved up when we had such good results, often forgetting we had some real stinkers of a match too.  These count just as much as the good matches and while nearly everyone is going to lose some matches, limiting the damage and keeping them as close as possible is another important factor in improving your rating.

Second, playing up is a good way to have the opportunity to improve your rating, but playing up will not automatically result in a bump up.  If all you do is lose, and lose badly when playing up, your rating can actually go down.  This is because you may be playing opponents that are also playing up, or opponents may simply be rated on the lower end of their level, and poor results against them will have negative effects on your rating.  It is possible that you can do more to help your rating by winning convincingly at level rather than playing up.  Of course, if you play up and do well and get some wins, that will likely result in your rating going up.

Third, and this one may be counter-intuitive, but playing with a lower rated partner can present more opportunity to improve your rating.  The way the algorithm works is that it compares the expected result with the actual result for a match.  If you play with a strong partner, you are supposed to win, perhaps easily, and a close win could actually hurt your rating.  But if you play with a weak partner and pull off an upset win, that can really boost your rating.

Fourth, and perhaps most important, improve your game.  Your rating is simply an indication of your ability based on your match results.  The three items above are all about getting the most out of your opportunities, but in the end if your tennis skills don't change, your results won't change significantly and your rating isn't going to change very much.  So go get a few lessons.  Identify your strengths and weaknesses and improve your weaknesses and come up with a game plan that accentuates your strengths.

As you go through your new season with a rating improvement plan in place, you may start to see results in the form of more wins or more competitive matches when playing up.  But how will you know if you rating is really improving?  In some sections, there are Early Start ratings that give you an idea, but those often don't come out until July, August, or later.  Another option for sections without early start ratings or those that don't want to wait is to get a mid-year Estimated Dynamic NTRP Rating Report that will give an accurate picture of your current dynamic rating and how each match has contributed to it.

Contact me for more information or even to get a report for your 2013 season to see why your rating ended up where it did.

Friday, December 6, 2013

Interesting USTA League Stats - What levels do players self-rate at and is there deliberate underrating?

When new players register to join a USTA League team, they are required to self-rate.  There are a set of guidelines to be used to have a player rate themselves at the right level so that they are hopefully playing competitive matches when they begin play.

With the data I have from generating Estimated Dynamic NTRP Rating Reports, I thought it would be interesting to look at what levels players self-rate at.  Here is what I found for 2013 self-rates.

This probably isn't a big surprise, with the most common levels being 3.0 and 3.5.  Players that self-rate are usually new or newer to the game, but many of these having some athletic background, and so you'd expect the lower to middle levels to be the most common.

It is interesting that even though the lowest level league is typically 2.5 and the guidelines above only going down to 2.5, there are a few players that self-rate at 2.0.

Next, I thought it would be interesting to look at some different areas to see if the self-rate profile was similar or different.

First, California.

The profile is very similar with a little more bias towards 3.5 than 2.5 and 3.0.

Next, Florida.

Again, a similar looking profile.

Let's go to a state that might be more unique by being an island with perhaps a different cross-section of players, Hawaii.

The profile remains very similar.

Last, let's take a look at Puerto Rico.

Here we see a different profile, and not just subtly different either.  The most common level is 2.5, a full two levels "left" of the rest.

It would be interesting to understand the reason for this.  It is certainly possible that in Puerto Rico, players' first exposure to tennis is often through USTA League and so you get more that are truly beginners and this chart simply is evidence of that.  However, there are some that believe that there is systemic and deliberate underrating that takes place in order to create teams likely to do well at Nationals.  There are disqualification provisions in place to try to prevent this and I've written about these before, but they aren't perfect.

This chart certainly isn't proof that deliberate sandbagging is taking place in Puerto Rico, but it certainly supports that hypothesis.

Wednesday, December 4, 2013

Throwing matches in USTA League - Does it happen?

In sports where there are levels of play, a longstanding issue is how to have players playing at the right level.  This is a perennial challenge with USTA League play too.

By definition, there will be higher and lower rated players within a given level and while matches will generally be competitive between players at the same level, the higher rated players are going to win more than the lower rated players.  For some on the lower end of the range for a level, it is tempting to think "If I were only at the next lower level, I could win more".

The dark side of USTA League is that some players will go out of their way to try to make sure they get bumped down a level so they can win.  They may do this by deliberately losing games or matches in order to cause their rating to go down.  This is certainly not in the spirit of the rules and unfortunate, but it happens.

In many cases, a player that is right on the margin between levels can get bumped down and their level of play is not so high that there is a major issue with them playing at the lower level.  However, it does become a major issue when a player tanks matches so much that someone that can compete and win at the higher level manages to get bumped down to a level where they are clearly at the wrong level.

We'd ideally have a system that can detect when matches are being thrown and compensate accordingly.  The challenge is that every player's play varies from match to match so simply having good/bad matches doesn't necessarily indicate suspicious behavior.  In generating Estimated Dynamic NTRP Rating Reports, I regularly see players that have a range of 0.5 and a bit more than that is not uncommon, especially when a player is improving during a season.

I recently came across a player that seemingly goes way beyond natural variance from match to match and would seem to be a clear indication of suspicious activity.  Here is their chart from their 2013 matches.

We can see that this player has matches rated as high as 4.96 and as low as 3.64.  That is a range of 1.32, the largest I've ever seen.  A 4.96 is a rating it would be reasonable for a 5.5 rated player to post and a 3.64 could easily be posted by a 3.5.  We even see a 3.69 result exactly one week before the 4.96.  This is an awfully big range and not what one would normally see from normal variance of play.

We can also see a group of lower rated matches all in September.  These matches are from a Fall league that counts towards ratings but does not advance to any National championships and is rumored to be used by some players to manage their ratings down.

Was this player throwing matches to manage their rating?  I can't say for sure, I'm just looking at numbers and charts.  There could have been factors involved that explain why the results are what they are.  I can only say that the wide range is suspicious and makes one go hmmmm.

Tuesday, December 3, 2013

Appealing a USTA NTRP Rating - Successes and what it says about estimated ratings accuracy

I wrote about the new rules for appealing year-end ratings and I've received feedback from quite a few of you about your success in having appeals granted.  Some have wanted to be bumped up while others bumped down and both groups have been able to accomplish their goal.

What is especially interesting is finding out when someone successfully appeals, as that provides an opportunity to validate the estimated ratings I have for a player.  Since there are ranges for appeals to be granted, finding out when one is lets me know if my rating was close or not.

Here are a few I heard about the past couple of days:

  • A self-rated 3.5 was bumped up to 4.0 but was able to appeal down to 3.5.  They'd played 6 matches so their range was 0.06 and my rating was 3.56 which was within that range.
  • A self-rated 3.5 wasn't bumped up to 4.0 but was able to appeal up.  The range for this is 0.04 and I had their rating at 3.45 so just 0.01 off from being right.
  • A 3.5 wasn't bumped up to 4.0 but was able to appeal up.  I had their rating at 3.52 so just 0.02 off from being right.
  • A 3.0 wasn't bumped up to 3.5 but was able to appeal up.  I had their rating at 2.99 which is within the range.
I generally aim to have my estimates within 0.05 of the actual rating, so all of these are within that.  And potentially each of these ratings are no more than 0.02 off from the actual rating.

Seeing that my ratings are this accurate great.  See this earlier post on other observations on accuracy.

And if you think you are close and tried to appeal, let me know if you did or didn't have it granted.

Monday, December 2, 2013

Year end ratings are out, how accurate are my Estimated Dynamic NTRP Ratings?

With year end ratings now being published, I took a quick look at some players to see how accurate my Estimated Dynamic NTRP Ratings are.  I plan to do a more in depth analysis later, but here is how I did on some initial checks.

I played on a 4.0 team that went to local playoffs this year and included a 3.5 playing up and several players that played up at 4.5 too.  In our early start ratings, two were bumped up to 4.5 while the rest stayed where they were and I had all of these correct, and in the year-end ratings both early start bump ups came back down as I predicted.  So 14 for 14 here.

I did reports for a 4.5+ team that went to Nationals and won it all, and as expected they had quite a few players bumped up.  I got every player on this roster correct except for one.  This included a few self-rated players as well as a 5.0 that won every match all year and did not get bumped up to 5.5.  11 for 11 here.

I just heard back from someone I did a report for that I nailed her rating too.  She was a 3.0 that I had at 2.99, just below the threshold to be bumped but close enough to appeal if I was correct.  She wasn't bumped in the year-end ratings but was able to successfully appeal.  So my 2.99 was correct or at most just a few hundredths off.

From this sample, I am 25 out of 26 correct, or 96%.  I don't know that when I do a more complete analysis I'll maintain this high percentage, but I've also gotten other feedback and checked a few others and found my ratings to be right now for most.

Stay tuned for more.

2013 USTA NTRP ratings are out - Why didn't I get bumped up (or down)?

With the publishing of the 2013 year-end NTRP ratings by the USTA, the inevitable questions begin, the main ones being "Why wasn't I bumped up (or down)?"

The algorithm used to calculate the ratings works off of the scores of your matches and the ratings of the players involved.  Your win/loss record actually isn't taken into account at all.  This can lead to players going undefeated but not getting bumped up, or having poor records and getting bumped up.

If you are baffled by why you weren't bumped up/down, an Estimated Dynamic NTRP Rating Report is a great way to find out and understand why your rating is where it is.  And while my ratings aren't perfect, of the 30 or so players I've checked so far today, 29 have been correct.

No matter what section you are from, I can generate a report.  So contact me if you are interested.

2013 Year-End USTA NTRP Ratings Released

It appears that the year-end ratings for the 2013 season have been released today as expected and can be accessed on the TennisLink Web-site.  All those I've checked have a date of 12/31/2013 and if any section hasn't been updated yet I'm sure it will be shortly.

Sunday, December 1, 2013

People really do shop on Black Friday rather than thinking about USTA NTRP ratings

Thanksgiving weekend is known for big sales as everyone looks for bargains as they begin their Christmas shopping in earnest.  For USTA League tennis players, it is also known as the weekend that precedes the Monday that year-end NTRP ratings come out.

With both of those in mind, it is interesting to take a look at the traffic to this blog.

As you might expect, my post on when year-end ratings will be out has garnered quite a bit of traffic, in fact resulting in near to new recent highs for page views on Wednesday, Thursday, Saturday, and today (Sunday).

What about Friday?  Page views on Friday were less than half of the other four days, so yes, even tennis players go shopping on Black Friday.

Thursday, November 28, 2013

Black Friday Sale on Estimated Dynamic NTRP Rating Reports for USTA League Players

In the spirit of Black Friday sales, I will be offering Estimated Dynamic NTRP Rating Reports at half price for one day only on Friday November 29th, 2013.  Contact me to get details or to order a report.

Why get a report?  Especially when the USTA is expected to publish year-end ratings this coming Monday?

First, some of you are wanting to know more specifically what your rating is.  It is nice to know you are a 4.0, but where in that range from 3.51 to 4.00 does your rating fall?  A report will give you an accurate estimate of where exactly your rating is.

Second, and probably more interesting to those who like details, the USTA isn't going to tell you how each match impacted your rating.  My reports will with a summary that tells you your highest and lowest rated matches and ratings, and a chart showing each match and associated match rating and resulting dynamic rating.

Third, my reports don't just give you a number.  I'll offer explanations for why matches are rated the way they are and answer any questions.

Here is a recent report I generated.

Current NTRP: 3.0S
Estimated DNTRP: 3.17
Match Record: 13-2
Sets Won-Lost: 27-7
Games Won-Lost: 179-90
Best Match Result: 3.5 on 10/13/13
Worst Match Result: 2.77 on 9/28/13
Highest Estimated DNTRP: 3.23 on 10/13/13
Lowest Estimated DNTRP: 2.97 on 6/8/13

I estimate your rating to be 3.17, well into the range for a 3.5. That is actually down just a bit from your high of 3.23 and it would even be a bit higher if it weren't for the 9/28 match. That match was a loss, and particularly the second set being 6-1 is what hurt you.

Your rating is pretty high both because you went 13-2 on the season, but also because you did so playing up at 3.5.

You will notice a few matches aren't in the chart. This is because they were played against other self-rated players before they had dynamic ratings. These should be included in the USTA's year-end calculations, and since they were all wins, two comfortable ones, they will likely help your rating a little bit.

But even with all that, I fully expect that you will be bumped up to 3.5 in the year-end ratings. This is particularly true because you did well in your playoff matches which will carry more weight in the year-end calculations. Four of your 5 playoff matches were well over 3.0.

So, in my estimation, you don't need to worry, you will be bumped up! Congratulations.

The example above is an individual report, but the discount applies to team reports too.

So if you want a report at a 50% discount, Friday the 29th is your day.

Monday, November 25, 2013

One week and counting until USTA League year-end NTRP ratings are released

It is the Monday before Thanksgiving, and with that USTA League players can begin the one-week count down until year-end ratings are released.

Year-end ratings are important for many reasons.  Some find a sense of accomplishment in getting bumped up.  Some may have struggled playing at a level and are interested to see if they'll be bumped down given them an opportunity to be more competitive.  And for everyone, these ratings will determine what level they are able to play at for 2014.

Now, some 2014 leagues started early and used early-start ratings to determine the level a player could play at, and so for these folks the year-end ratings can be a confirmation of what the early-start rating indicated.  But it is not unheard of for someone to be bumped up on the early-start list but not bumped in the year-end ratings.  Of course, it can go the other way as well.

In any case, if you can't wait, an Estimated Dynamic NTRP Rating Report is a great way to not only get a preview of what your rating is likely to be, but also see all the details of how your season went and how each match contributed to your rating.  And you aren't limited to getting a report for yourself!  I've had numerous people get reports for others as gifts.  Let me know if you are interested in a report.

Friday, November 22, 2013

New rules for USTA League NTRP rating appeals

The original content of this blog entry described the appeal rules as of 2013 and was based on a communication from the USTA at that time and thus quite dated now.  My understanding is the appeal rules have changed and so what was written no longer applies.  Please do not base any assumptions or expectations on what appeals may be granted based on what you'd read here before.  Please see this more recent article on what the rules are based on the 2019 USTA League regulations.

USTA League Mixed Nationals this weekend - rain rain go away

While the 2013 USTA League year ended on 10/27 with the completion of all of the 18 & over and 40 & over Nationals for men and women, Nationals in other divisions continue.  This weekend has the Mixed 18 & over Nationals for 6.0, 8.0, and 10.0 levels taking place in Tucson.

Unfortunately, as I write this Tucson is getting one of its few days of rain a year.  And in fact the forecast doesn't look great for the whole weekend.  Let's hope they find a way to get the matches in.

Wednesday, November 13, 2013

More details on when USTA 2013 year-end ratings will be available

I wrote a few weeks ago about the 2013 USTA year being over on October 27th and the USTA spending November calculating year-end ratings.  The ratings themselves are usually released on the Monday after Thanksgiving, and usually that afternoon, so that would put December 2nd as the likely release date.

Given the increased interested in my Estimated Dynamic NTRP Rating Reports, not everyone wants to wait that long to have an idea of what their rating will be.  I've recently generated reports for players in some new places including several new parts of Michigan, Georgia, Arkansas, and more.  Contact me to join the folks getting an early preview of how their rating gets calculated and what it will likely be.

Tuesday, November 5, 2013

2014 USTA League teams are forming soon, who should you recruit for your team?

In many sections, USTA League tennis is a year round endeavor with multiple different leagues and age groups available to most players.  But in most sections, the main adult leagues (18 & over and 40 & over) are played in the Spring with some starting earlier, as soon as January, in order to not have the two leagues completely overlapping.

Given that it is November, January isn't that far away and it is time to start forming teams and recruiting players.  But there are a couple of challenges in doing this.

It can be difficult to recruit the right players in November as year-end ratings aren't out yet and some players may be on the bubble of being bumped up/down and you don't want to find out in December that those 4.0s you recruited are now 4.5s and you have to go find more 4.0s to fill your roster out now that other teams already grabbed them.

Then the USTA only tells you a players rating to the half point and you don't know really how strong a player is within that range.  Certainly if you know and play with a player, you have a pretty good idea, but simply looking at past season wins/losses may not be representative of how strong a player is.

One solution to both these challenges that can be an aid in recruiting and forming teams are my Estimated Dynamic NTRP Ratings.  With ratings to the hundredth, you can both know how highly rated a player really is as well as have a good idea of if a player will be bumped up or down.

Individual reports can tell you a lot about a player's profile over the year and where they are currently, but you don't need that much detail to identify who to recruit all the time.  Team reports are a standard offering I have and show less information but for a whole team so they are an option to aid in recruiting.  But sometimes you just want lists of ratings and I do offer these too.  Pricing is dependent on how many ratings and a few other factors so contact me for more details and to get a quote.

Monday, November 4, 2013

Another team report customer is headed to Nationals

While the 18 & over and 40 & over Nationals for 2013 are complete, there are a few divisions that have their 2013 Nationals occur in early 2014.  As such the playoffs and Sectionals for these divisions can happen at odd times of the year, and in one section they recently held their Sectionals and another of my team report customers pulled out a 2-1 win in the final and will be headed to Nationals in the Spring.  Congratulations and good luck!

The USTA League year is over, now we wait for 2013 year-end NTRP ratings

All indications are that all the matches that will be used to calculate 2013 year-end NTRP ratings are now complete, and now we wait for the year-end ratings to be published in 4 weeks or so.

I actually believe the "USTA year" ended a week ago Sunday with the completion of the last 40 & over and 18 & over Nationals.  But any fall leagues or early start leagues that played matches on or before October 28th should also have those matches included in year-end calculations.  See this write-up for a little more detail on how I understand the whole process to work.

But if you are impatient (I know I am) and don't want to wait for the USTA, let me know if you'd like to get an Estimated Dynamic NTRP Rating Report that tells you what your rating will likely be.

Note: I have subsequently confirmed that October 27th was the end of the 2013 USTA year.

Tuesday, October 29, 2013

Interesting USTA League Stats - Histogram of NTRP ratings down to the tenth

Next in my series of posts on interesting stats from the data I collect for the Estimated Dynamic NTRP Rating reports I generate, I took a look at how many players are at each rating level down to the tenth.

Why down to the tenth?  There was a discussion on Talk Tennis about the issues with the new "plus" leagues where it was hypothesized that there were clusters of players in certain ranges and how, naturally or otherwise, a slight movement of the range for each NTRP level might result in better alignment with those groups of players.  With my ratings, we should be able to chart the ratings rounded to the tenth and clearly see if and where there are any clusters.

Here is the chart:
From this, it doesn't appear there are any abnormal peaks or valleys that would indicate such clusters exist.  There is a peak at 3.2 a slight dip at 3.4, then another peak at 3.5, but this could potentially be explained by the fact that this chart includes both men and women, and perhaps women have their peak at 3.2 and men at 3.5 and when put together, you get the chart above.

So we don't see any odd clusters.  It could be that my ratings aren't accurate and so don't show them, but given my accuracy in predicting DQs and bumps, I think it is more likely that my ratings are pretty accurate and there aren't any significant clusters of players around a particular rating other than the normal large group of players at the NTRP 3.5 and 4.0 levels.

Sunday, October 27, 2013

A team report customer wins USTA League Nationals

I had a number of teams that purchased reports from me to aid them in scouting opponents as well as their own teams, several advanced in the playoffs, a few made it to Nationals, and today one of them won it all.  They've made nice comments about how much the reports helped them scout and plan, and I appreciate them, but the players still had to go out and win the matches and that is what they did, so kudos to the whole team!

Friday, October 25, 2013

The last 2013 USTA League Nationals are going on now

Ok, it isn't really the last, as there are some mixed and perhaps other leagues that have their Nationals in November, but for the 18 & over and 40 & over leagues, this is the last weekend of Nationals in what has been an October (and bit of September) packed with play.  With the introduction of the 40 & over league this year, there was a bunch more play.

In Tucson this weekend is the 18 & over 3.5 Nationals.  I have a team I've helped with reports playing there so will be following it closely.

Then in Indian Wells is the 40 & over 4.5+ Nationals.  I also have a team I've helped playing there so will follow as well.

Stay tuned for updates as I'll likely take a look at how my ratings do prediction matches.

Saturday, October 19, 2013

Another Estimated Dynamic NTRP Rating Report Customer Reaches USTA League Nationals Semis

Several more USTA League Nationals are taking place this weekend and I was pleased to see another one of my customers having made the semis.  Good luck guys!

Friday, October 18, 2013

Now available, Mixed Exclusive Estimated Dynamic NTRP Rating Reports for USTA League

Most people that play USTA League plan in a men's/women's league, but many also play in a mixed doubles league.   There are some that only play mixed though, and for these, the NTRP ratings are calculated a little differently.

If you play in at least three men's/women's matches, your rating will be calculated based on only those and your mixed results aren't factored in.  However, if you only play mixed, you will be given a Mixed Exclusive (M) rating.

A mixed exclusive rating is used only for mixed leagues, and if you have one and decide to play a men's/women's league, you have to self-rate for that league.

So, these M ratings are a bit unique as they would seemingly have to be calculated for everyone who plays mixed in case they don't play men's/women's, but then they aren't used.  In theory, a player could be a 4.0C (men's/women's rating) but a 3.5M based on their mixed matches if they hadn't  played men's/women's.

I've toyed with calculating M ratings for awhile now, but believe I have something working reasonably well now, so if you only play mixed, or play both mixed and men's/women's and just want to know what your M rating would be, I can now calculate these as part of my Estimated Dynamic NTRP Rating Reports.  If you are interested in a report, contact me.

Wednesday, October 16, 2013

When will USTA 2013 year-end NTRP ratings be released?

Most of the National Championships for USTA League tennis are being played this month, and with their completion, year-end ratings can be calculated.  Here is my understanding of the timeline.

  • September / October - Adult 18 & over and 40 & over Nationals take place.
  • End of October - The "USTA year" comes to a close and with that, the last matches to be included in year-end calculations have been played.
  • November - Year-end calculations are performed including benchmark calculations taking into account the Nationals that were just completed.
  • End of November / Early December - 2013 year-end ratings are published and available on TennisLink.
The exact "USTA year" may vary a bit and depend on when exactly the last Adult Nationals finish and when the last weekend of October or first weekend of November falls.  And the year-end ratings are usually released on the Monday after Thanksgiving, but I don't know that there is a guarantee of that.

Many players aren't going to Nationals and aren't playing in a fall league that counts towards their rating, so all the matches that count for them have been played.  If you are one of these and are anxious to know what your year-end rating may be, or just want to know more accurately where your rating falls within your level, an Estimated Dynamic NTRP Rating Report is a great way to find out.  The report will show you your rating and how it changed, match by match, and I'll also comment on the likelihood that you get bumped up or down.  Contact me if you are interested.

Update: I've confirmed the last matches for the 2013 league year were played on 10/27.  Click here for more information.

A report customer wins a National Championship

I did several reports for a player in my section earlier this year, and was pleased to find out this morning that her team won Nationals last weekend.  Congratulations!

Monday, October 14, 2013

Another report customer advances to USTA Nationals, this one a Mixed team

I've had the opportunity to help a number of teams make their way to Nationals by providing reports on team members and opponents.  I'm not kidding myself into thinking they get there because of the reports, they still have to go out and win the matches on the courts, but feedback has been consistently positive indicating that the reports helped them with line-ups.

I'm pleased to report that another team I did reports for has qualified for Nationals, this one an 18 & over mixed team.  Yes, that is right, I am now doing reports for mixed (more on that later).

Something that was interesting about looking at mixed was comparing their normal dynamic rating with what their mixed exclusive rating would be.  For many, they were remarkably similar, but there were a few where they were quite different, and it was good to get feedback that where the mixed rating was higher, that player was actually a better mixed player than not.  So I must be doing something right as the ratings seemed to reflect reality.

This team had to navigate 4 matches in Districts, and then a semi and final to win their Sectionals.  They indicated that the reports were "... incredibly helpful in setting lineups and understanding what our chances were."

As you might imagine, I'm now working on reports for their competition at Nationals.

Good luck team!

Friday, October 11, 2013

More Interesting USTA League Stats - Looking at gender and NTRP level

I received feedback on the last interesting stats blog post showing some interest in seeing a chart that combines gender and level.  For those that wanted that, here it is!

This gets a lot more complicated looking, so some explanation is in order.  And you can click on the image to see a larger rendering which may be easier to read.

Each pair of columns are for men and women in the indicated section.  Each column is showing the percentage of men/women at the level indicated by color.  The total height of the column is the percentage of players within that section for that gender.  Make sense?

I'm sure lots of observations can be made.  Feel free to leave a comment with yours.

More Interesting USTA League Stats - Do more women or men play USTA League?

Next in my series of posts on interesting stats from the data I collect for the Estimated Dynamic NTRP Rating reports I generate, I took a look at how many men and women play USTA League by section.

Here is the chart:

Perhaps surprisingly, it varies quite a bit from section to section.  Hawaii has the most men at 62% while New England has the most women at 69%.  Northern Cal and the Caribbean have high percentages of men too while the Southern section has a large percentage of women.

Is there an "equal opportunity" section that is 50/50?  It appears not, with the Pacific Northwest being the closest at 49% men and 51% women and Texas next at 48%/52%.

Now, I don't have absolutely every USTA match played in 2013 in my database, but I have a large enough sample (thousands of players in each section) that they are representative.

Thursday, October 10, 2013

Estimated Dynamic NTRP Ratings for Northern Virginia (NOVA) Now Posted

I've had a lot of report customers in Northern Virginia so I decided to post a list of my Estimated Dynamic NTRP Ratings through July 1st of this year for that area.  Check it out here.

Wednesday, October 9, 2013

It is time for USTA Nationals, and all the sandbagging accusations that come with it. Here is a solution.

It is October, and for those that follow USTA League you know that Nationals are taking place for the 18 & over and 40 & over men's and women's leagues.

A few of the levels have finished, and as is usually the case, particularly at the lower levels, the observations and accusations about players that appear to have skills well above the level they are playing at and are sandbagging are flying.

The scenario is this.  Players that haven't played USTA League before self-rate according to documented guidelines.  Unscrupulous captains and players may deliberately rate a level or two too low in order to have a competitive advantage.  There are provisions in place to automatically bump a player up a level if their results indicate they self-rated too low, but at the lower levels, there is a large buffer to allow a player to improve without getting disqualified at a given level.

The result is that you find several to many of these players at Nationals, someone that looks like a 3.5 or even perhaps a 4.0, playing at 3.0 for example.  One could argue that to get to Nationals and do well, you actually need to have several of these players on your roster and there is some truth to that.  If you are the best from your area, district, and section, you probably are playing at the very top of it not above the level in question.

Now, one might argue, and many have, that an easy solution to this is to not allow self-rated players to play in the playoffs or at least not allow them to play at Nationals or Sectionals.  There is some merit to this, but it would only be a partial solution as it only delays the problem and doesn't address a segment of the players at Nationals.

Go back to the scenario above.  If our player is really a 3.0 and self-rates at 2.5, they likely get bumped up to 3.0 at year end and have a 3.0C rating.  Now, in playing a year, they probably improved some and are able to play at a 3.5 level.  But they are a 3.0C so they sign up for a 3.0 league the next year, and with a little coordination join a team that has a few other players in their same situation.  They dominate their local league, start getting excited about the possibility of going to Nationals and get some lessons and their games improve to a near 4.0 level.

This team now shows up at Nationals and looks like a bunch of sandbaggers, just like the self-rated player would look, but they have followed all the rules and are C-rated players so can't be DQ'd and the proposed rule not allowing self-rates to go to Nationals doesn't affect them.

Second, players playing well above their level didn't necessarily self-rate too low.  Some players simply decide to improve their game and the yearly cycle of re-leveling players allows for someone to improve enough to be well above their level.

This second issue is just an unavoidable part of having tiers/levels of play and these players shouldn't be punished.  There will always be players at the top of the tier and even above it that are on their way to being bumped up.  The very nature of Nationals dictates that you have to have these players to get there, so we shouldn't expect 3.0 Nationals to look like a regular season 3.0 match in our local league play.  By definition almost, it is going to look like 3.5 players.

Now what I'd propose would help address the first issue of self-rated players self-rating too low would be two things.

First, while I can see the argument for not allowing them to go to playoffs, another solution would be to tighten up the buffer given to allow for natural improvement.  Simply lower the threshold for strikes and these players would get DQ'd and bumped up and be ineligible to play on the team.

Second, and more important, I would institute a rule that any self-rated player that gets DQ'd or bumped up in their first year should be treated as a self-rated player again the next year.  And if it happens in their first two years, they are still treated as self-rated in year three, etc.  I don't think you could extend any prohibition on going to Nationals to year two, but this would at least preclude them from sandbagging their first year to get a C rating and then being protected from DQs.

There is no panacea for this, having levels of play will always result in issues where the levels meet, but a few minor changes could reduce the opportunity sandbaggers have to cheat the system.

Friday, September 27, 2013

Estimated Dynamic NTRP Ratings for Los Angeles

I've done a number of reports for players in Southern California so I thought I'd post a list of ratings for the Los Angeles area thru 7/1/2013.

As always, if you are interested in an up-to-date rating and full report, contact me.

Wednesday, September 25, 2013

Nearing the end of the 2013 USTA season, what is your dynamic NTRP rating?

Sectionals in the 18 & over and 40 & over USTA Leagues are complete and teams are headed to Nationals which will take place in October.  That means the 2013 USTA year is about complete and year-end ratings will be out in just a couple of months.

While the ratings come out right around the end of November, the USTA season actually runs from roughly the beginning of November to end of October.  Nationals are generally done by then and the month of November is spent doing the year-end calculations and establishing the year-end ratings for each player.

If you are hoping to cement your bump up to the next level but aren't going to Nationals, you may still have a chance to get some matches that count in.  Some sections have fall or early start leagues that count towards your rating and those leagues are going on now.

If you are interested in getting a preview or sneak peak into what your year-end rating may be or where it stands right now, an Estimated Dynamic NTRP Rating Report is an excellent way to do so.  Or if you are needing to form teams but can't wait for the year-end ratings to come out, I can generate team reports or lists of players and ratings to aid in selecting the best players at a given level.  Contact me to see what can be done.

Saturday, September 7, 2013

More unexpected DQs and non-DQs explained

I've explained a number of DQs in the past (see here and here for a couple) using my Estimated Dynamic NTRP Ratings and someone shared with me an unexpected DQ as well as an unexpected one during the Sectionals in the Eastern section of the USTA that I took a look at.  Once again, my ratings explain them showing how accurate they are.

First, this player had some very good results and the team fully expected him to be DQ'd but decided to just keep playing him as the Eastern section doesn't reverse matches for DQ'd players.  Despite a list of easy straight set wins, through Sectionals, he wasn't DQ'd.

My ratings do show that he likely had a strike from his first match of the year, but then managed to have his rating hover between 4.5 and 4.6 in large part because of a very low match rating in his second match.  Here is his full chart.

So while I can't confirm my ratings are exactly correct in this case, we only know he wasn't DQ'd, I seem to have gotten this one right.

Second, this player started the season as a 4.0 but got DQ'd to 4.5 during the mixed season, and so had to enter the men's season as a self-rated 4.5.  He went into Sectionals with one win (6-4,7-6) and one default win and proceeded to win 4 matches at Sectionals, 3 in match tie-breaks, and gets DQ'd which was very unexpected.

My ratings show that it is possible that he actually had 4 strikes at Sectionals, and was able to get the 4th simply because the match was played the same day and they may not have had a chance to do the calculations before the 2nd match.  Here is his full chart.

This shows pretty clearly that the first match at Sectionals was the key one generating a huge match rating of 5.33.  When the next two matches were also very good, his fate was sealed.

How did he generate such a high rating in that first 8/23 match?  He played with a partner that happened to be rated on the lower end of the 4.5 range and against two very strong 4.5s (likely to be bumped up).  Being only his second rated match, his rating is calculated as what it would have to be to make the match result correct and that was 5.33.

So my ratings have again gotten it right.  A player everyone thought would be DQ'd wasn't, and a player that on the surface looked unlikely to be DQ'd was.

If you've been DQ'd, and especially if you can share your DQ letter with me, let me know.

Wednesday, September 4, 2013

Last few USTA Sectionals this weekend - Mid-Atlantic and Texas

The USTA League season for the 18 & over and 40 & over leagues is coming to a close soon with Nationals in October, and it looks like the last of the teams to qualify will be decided this weekend.  The Mid-Atlantic and Texas sections are holding their 40 & over Sectionals and I know one of my Estimated Dynamic NTRP Rating Report customers is interested as one of their opponents at Nationals will be coming out of one of these sections.

Good luck to all.  I've only been to Nationals once, but it was a great experience and we had a blast even if we didn't win it all like we hoped.  So enjoy trying to get there!

Saturday, August 31, 2013

More interesting USTA League stats - Which court does the winning team win most often?

Continuing on in my effort to share interesting stats from the data I collect for the Estimated Dynamic NTRP Rating reports I generate, I took a look at how often the winning team in a match wins the different courts.

Specifically, I took a look at all team matches that were 2 singles and 3 doubles.  Here is the percent of the time the winning team wins each court.

CourtWinning %

It isn't a huge margin, but pretty clearly the winning team is going to win court 2 doubles more often than any other court.  And court 1 singles is won the least often.  And interestingly, all of the doubles courts are won more often than either of the singles courts.

What can we take away from this?

First, it appears that the key to winning is having good doubles teams and not singles guys.  This goes against intuition a bit (IMHO) that the easiest way to having a strong team is to have 2 lock-down singles guys and 1 great doubles team (this requires the fewest strong players to win a team match, just 4).

Second, you need depth at doubles.  Whether it is because captains flip-flop and play their best doubles team on court 2, or just because the better team is deeper and their second best doubles team is better than the opponent's, the winning team wins court 2 doubles most often and court 3 doubles next most often.

Third, and this one probably isn't a surprise, it looks like the most likely court to be thrown when juggling line-ups is court 1 singles with the winning team losing it more often than court 2 singles.  And court 1 doubles also suffers from this too.

What do you think?  What other interesting stats are you interested in seeing?  Let me know.

Tuesday, August 27, 2013

Early Start Leagues and USTA Nationals, are they fair?

I was contacted by a report customer today asking why her 3.0 team was going to have to play against a 3.5 at Nationals, and not just a 3.5 but one that had won a match playing up at 4.0.  The answer is, Early Start Leagues.

In this case, the player in question played in a district where the 40 & over league was an Early Start League this year.  This means that, typically for court scheduling and the like, the 2013 league started play before year-end ratings came out and so it is designated as an Early Start League (ESL).  Because the year-end ratings haven't come out yet, their year-end rating can't be used to determine the level they are eligible to play at.

What sections do to address this is to have Early Start Ratings (ESR) that come out mid-year, typically in July or August.  These ratings are a "sneak preview" into what a players year-end rating may be and are used to try to get the players in an ESL playing at the right level.  This is a good idea and usually works, but sometimes it doesn't.

In this case, the player was a 3.0 in 2012 and played up at 3.5 losing all her matches prior to the ESR date and her dynamic rating was just below 3.0, so her ESR was still 3.0 and she proceeded to begin play in the ESL on a 3.0 team.  She played one match before year-end ratings came out and it was a thumping of the opponent which caused her rating to go up and she ended up being a 3.5 in the year-end ratings.  Note that my ratings correctly had her a 3.0 ESR and also had her being bumped up at year-end.

So she is now a 3.5, but playing in a 3.0 flight.  What are the USTA's rules for this?  See page 12 at this link, but the summary is that sections have options, and it appears option 2 is employed by the section in question which allows a player to continue play in the ESL using their ESR unless their year-end rating was clearly above level.  In this case, the player had just eked over the threshold to be bumped up so she wasn't clearly above level.

So she gets to play in the 3.0 flight, but must now play as a 3.5 in the 18 & over league (not an ESL), and also decides to play up in a 4.0 18 & over flight.  She does get a win at 4.0 (4 losses too), and also loses 3 3.5 matches, so she isn't dominating, but her 3.0 team advances to Nationals.

To opposing teams then, it looks like she is a 3.5 that has won at 4.0 and gets to play against 3.0s at Nationals.  This is all per the rules so is fair in that regard, and many of the other players that will be at Nationals are also effectively 3.5s so the play may be competitive, but should the USTA allow this to happen?

Comments welcome.

Monday, August 26, 2013

More teams advance to USTA Nationals with the help of Estimated Dynamic NTRP Rating reports

USTA League Sectionals took place this past weekend in many areas and I'm pleased to say that two more teams I helped with individual and/or team Estimated Dynamic NTRP Rating reports have advanced to Nationals.  That brings the tally to four.  Thankfully, all four are at different levels or different divisions so they won't be facing each other :)

Unfortunately, one other team I was helping did not advance, losing on the sets lost tie-breaker to a team they beat.  The team I was helping, team A, went 1-1 in their first two matches, their loss being a heart breaking 3-2 loss where all the losses were in match tie-breaks, and they needed to beat the lone remaining 2-0 team in their sub-flight 4-1, or a 3-2 win with a little luck would do it too.  Unfortunately, they won 3-2 but lost a set in two of the wins so they lost more sets and lost that tie-breaker.

This isn't the first time a team has won the head-to-head but lost this tie-breaker, but perhaps it will be the last?  I'm was told that a USTA official said next year, head-to-head will be the first tie-breaker.  Too bad it wasn't this year!

Good luck teams!

Friday, August 23, 2013

More Sectionals take place this weekend

It is August, so there are Sectionals going on somewhere most every weekend.  This weekend has 18 & Over Sectionals going on in Northern California and 40 & Over Sectionals in the Pacific Northwest.  Alas, I was hoping to be playing this weekend but my team lost in our local playoffs and didn't make it to Yakima.

However, I'm still involved as I have teams that have gotten reports participating in both of these Sectionals.  Good luck to those teams!

Thursday, August 15, 2013

Updated interesting USTA League Stats - Ratings by Section - Florida and Midwest added

I've written a few blog posts with interesting ratings, and below is an updated chart showing the ratings by section with Florida and the Midwest added.

NTRP Ratings by Section

Florida is similar to the Mid-Atlantic with a pretty good distribution towards the higher rated players, but is not to the same levels that Northern Cal, Southern Cal, and Texas are.  The Midwest is also very similar to Florida and Mid-Atlantic.


Wednesday, August 14, 2013

Can a 3.5 USTA League team make it to 3.5 Nationals?

The subject may seem a bit odd, but there is a common perception that a team of players that are actually 3.5s has no chance of advancing to Nationals.  Instead a team must be filled with ringers and self-rated players that under rate themselves and manage their to avoid strikes.

To test this, I thought I'd take a look at a couple 3.5 teams headed to this year's Nationals.  The teams I'm looking at are from Houston, an area notorious for ratings manipulation shenanigans, and the Northwest Washington district that has had a strong record of sending competitive teams to Nationals.  I'll be using my Estimated Dynamic NTRP Ratings to do the analysis.

First, Houston.  This team has a big roster with 7 benchmark rated players and a whopping 14 self-rated or appeal players.  They won their local league with a 7-1 record, winning 32 of 40 courts during the year and then turned it on in local playoffs going 3-0/14-1.  At Sectionals they went 3-0/12-3 winning their flight and then 2-0/7-3 in the semis and finals.

They did have some attrition along the way with 3 of the self-rates being DQ'd, one at Sectionals.  Note that my ratings agree with 2 of them including the one at Sectionals, and perhaps the other was an administrative DQ.  Including those DQ'd players the average rating for the team is 3.51.  But even without them the average is still 3.46.  With the players still eligible for Nationals, they could run out 5 courts with players all rated 3.48 or higher.

This is certainly a strong team with 3 that have already effectively been bumped up and a number of others (not withstanding results of the Texas Fall league being used to manage ratings back down) that will follow suit at the end of the year.  One can certainly make the case that very few of these players are "real" 3.5s.

Next, Northwest Washington.  This team went 8-1/35-10 in league play, going 2-0/9-1 in local playoffs.  At Sectionals, they went 2-0/8-2 in their flight and then won the final 3-2.  Their roster includes 5 self-rates and 4 benchmark players.

None of their self-rates were DQ'd, although 2 of them I do have rated over 3.50.  Their team average rating is just 3.35, but their top-8 average is 3.49 and all are at 3.35 or above.

This team also appears strong, but perhaps not as strong as Houston, and has a number of players that will likely be bumped up at year-end.

Having said all this, you would expect teams that do well and advance to Nationals to have strong players at the top of their rating range and even above.  Players certainly improve and someone has to be bumped up, and you would expect players on teams that do well to fall into this category.

So technically, both teams are filled with 3.5s that are eligible to play.  On the surface it does appear some players, more so from the Houston team, self-rated artificially low and thus aren't really 3.5s, but from what I've presented, I can't say whether this was deliberate or innocent, but it is a shame if it is the former.

It will be interesting to see how these teams do at Nationals, and even more interesting if they happen to face each other.  Check back in a couple months and I'll take a look at how each does at Nationals!

Monday, August 12, 2013

Comparing an Estimated Dynamic NTRP Rating Report with a real USTA League DQ letter

I created some Estimated Dynamic NTRP Rating Reports for a team last week and one of their players had been three-strike disqualified so I had the opportunity to take a look at it.  This isn't new, I've done this many times and generally find that I can explain the DQ.

What was interesting about this one was that the DQ letter they forwarded to me not only identified which matches were strikes, but listed the dynamic rating for each match.  This was a huge opportunity for me to do a more detailed comparison and here is what I found.

The player in question had self-rated as a 4.0 and played 7 matches, all doubles, going 6-1.  Here are the scores, the dynamic rating in the DQ letter, and my estimated rating after each match.

Match ResultDynamic
Won 7-5,0-6,1-03.974.01
Won 6-4,6-14.364.49
Won 7-5,6-14.234.22
Won 6-2,7-64.164.15
Lost 6-3,6-24.174.17
Won 6-2,4-6,1-04.194.17
Won 6-4,7-54.204.20

While my estimates weren't perfect for all 7 matches, they were close, and from the 3rd match on no more than 0.02 off and exact on 2 of the ratings.  I think that is accuracy I can live with.

If you received a DQ letter that included your ratings like this player did, please contact me and I'll generate a report for you for free comparing my estimates with the actual ratings and helping you understand why the ratings were what they were.  You may also contact me if you are just interested in purchasing an individual or team report as well.

A Northern California team report customer advances to USTA Sectionals

This weekend was a busy one for USTA League playoffs and in addition to the Pacific Northwest team that won their section and is headed to Nationals, I helped a team in Northern California that won Districts and is headed to their Sectionals in a couple weeks.  This team is already busy preparing, and I just generated reports for all the teams they may face there.  The teams look very close, so the match-ups they can get with the help of the reports may make the difference for them.

Sunday, August 11, 2013

Another report customer advances to Nationals

This one was inevitable no matter who won as I'd done reports for both teams, but another team I've done reports for, this one from the Pacific Northwest Section, is headed to Nationals.

As I've done before with some playoff match-ups, I took a look at  how my ratings did predicting games.  Here is how my ratings did predicting the matches in the final:
  • A 3.64 beat a 3.51 7-6,6-0
  • A 3.63 beat a 3.50 6-0,6-4
  • A 3.48/3.47 beat a 3.26/3.28 6-2,4-6,1-0
  • A 3.49/3.63 beat a 3.37/3.83 6-1,6-3
  • A 3.28/3.31 beat a 3.42/3.39 3-6,7-6,1-0
Technically, my predictions went 3-2, but the 2 losses if not expected, are explainable.

Any time doubles parters are nearly a full rating apart, it can be an easy target for the opponents to pick on the weaker player and the stronger player can't get involved.  This would explain the 4th match above.

And while the 5th match above was an incorrect pick, the stronger team did win more games.  Unfortunately for the losing team who lost 3-2, they had the on paper stronger team that lost this 5th match.

Good luck at Nationals guys.

Saturday, August 10, 2013

More teams advance in USTA playoffs with the help of Estimated Dynamic NTRP Rating Reports

The Pacific Northwest Section of the USTA is holding their Sectionals for the 18 & over league, and I just learned that two teams I've done individual and team reports for are going to face off in the final.  I can't take credit for them making it this far, they've had to play well on the court, but they've both said the reports helped them prepare and know what to expect going in to the matches.

The good news is, one of them is going to Nationals, joining another team I helped from Northern California as teams making it to their respective Nationals.  And others I've helped still have their Sectionals to play.

Good luck!

Thursday, August 8, 2013

Golf has handicaps, tennis has NTRP ratings

In any recreational sport, there are players with varying degrees of skill, the full range from beginner to aspiring or former professional.

In golf there is a handicapping system where by a player enters their scores and the course/tees played into the system and a handicap is calculated.  This number, very roughly how many shots over par a player may be expected to shoot on a regular basis, allows players of different ability to compete on an equitable basis.

For example, a player A with a handicap of 10 plays player B with a handicap of 6, player A will "get 4 strokes" in order to be able to equitably compare scores at the end of the round.  In theory, two players of any skill set can play and have the playing field leveled through the use of their handicaps.

In tennis, we don't have a way for a near pro to play a beginner and have a level playing field, but we do have the NTRP rating system used by the USTA to rate players at several different standard levels, so that players of the same level can play and have competitive matches.

Of course, no system is foolproof or safe from being manipulated, and this happens with both golf and tennis.  Some golfers choose not to enter good rounds because it would lower their handicap and they'd get fewer strokes, and some tennis players choose to throw matches to lower their rating so they can play at a lower level against weaker competition just so they can win.  The fact that either of these occurs is unfortunate.

In golf, the handicapping system has some provisions built in to try to combat manipulation.  For one, only your 10 best rounds out of your last 20 count towards your handicap.  So unless you are going to throw a lot of rounds, the bad ones don't count and only your good rounds that reflect your capabilities will go into the calculations.

With the NTRP system, to my knowledge, there is no such omitting of results, but perhaps there should be.  Further, some sections/districts choose to include or not various leagues and tournaments.  This gives some players ample opportunity to use "secondary" leagues to throw matches and lower their ratings.  If I were doing the system myself, I'd probably build in some checks to preclude counting thrown matches or throw out highs and lows in the calculations.

To be fair, the NTRP system does have year-end calculations where different matches are weighted more heavily, specifically those in playoffs and those played against players who played in the post-season.  By doing this, the matches that players are likely trying their best in count more which makes sense.

And this is the time of year that these post-season matches are taking place, so these are the ones that will count the most.  Good luck to all those playing in playoffs.  Go out there and play your best and if you get bumped up, congratulations and embrace the challenge of playing tougher opponents next year.

Tuesday, August 6, 2013

Have you been 3 strike disqualified in USTA League tennis? Get a free report that explains the DQ

Analyzing USTA League disqualifications is one of the interesting things I get to do with my Estimated Dynamic NTRP Ratings.  I'm usually able to predict or explain most DQs which is a confirmation that my algorithm is pretty darn close to estimating ratings correctly.

But when I can't explain one, the details of the DQ allow me to look at my algorithm and figure out how I can fine tune it a bit more.  Because this review is so valuable to me, I'm offering a free Estimated Dynamic NTRP Rating Report to the first 5 USTA League players to contact me that received a DQ during the 2013 season.  In order to qualify for the free report, you'll need to send me the actual DQ letter you received with the details about which matches resulted in strikes.


Update: I've made the offer again for 2014.

Sunday, August 4, 2013

More interesting USTA League statistics - Ratings by Section

I wrote yesterday about some interesting statistics I can look at based on the data I analyze for my Estimated Dynamic NTRP Rating Reports.  I took a deeper look and broke out the percentage at each level by the sections that I have a reasonable amount of data for.

NTRP Ratings by Section

This gives an interesting picture of the distribution of players in each section.

Northern Cal, So. Cal, and Texas clearly have the fewest 2.5s and below and not surprisingly, they have the most 4.5s and above.  The number of 3.5s is interesting similar across all of the sections.

This analysis started in response to a dialog about Atlanta vs NorCal and high rated players, and while this simply includes Atlanta in the Southern section, but this shows a higher percentage of strong players in NorCal than Southern.  Unfortunately for NorCal, it appears SoCal has you beat slightly in that category.

Note that this analysis is based on data that numbers in the thousands of players in each section listed above, but not necessarily every player.  And I left out some sections where I have data but the count is smaller and may not be fully representative.

Saturday, August 3, 2013

Some interesting USTA League stats - Players by NTRP level

As a by product of generating individual and team Estimated Dynamic NTRP Rating reports, I have a fair amount of data from which I can calculate some interesting statistics.

A Talk Tennis thread on sandbagging turned into a discussion about how Atlanta and the San Francisco Bay Area compared and I posted some stats on how many players there were by level from each area.  I thought it would be interested to take a look at the same stats for all the data I have and here it is.

  • 2.5- - 5%
  • 3.0 - 21%
  • 3.5 - 36%
  • 4.0 - 28%
  • 4.5 - 9%
  • 5.0+ - 1%

USTA League Players by Rating (%)

These numbers are probably not a surprise, but it is still interesting to see them for real.  The 3.5 level has the most players followed by 4.0 and then 3.0.

Do you have another stat you'd like me to post?  Leave a comment and let me know.

Note: These stats are for about half the sections in the USTA but are from a large enough data set that they are probably representative of USTA participation as a whole.

August is the month for USTA Sectionals

For teams looking to get to USTA League Nationals, August is an important month.  With the realignment of the leagues to add the 40 & over league in addition the 18 & over league, some sections may have had playoffs/districts/sectionals for one of the leagues already, but for most, August and September is the time that teams advancing to Sectionals and Nationals are determined.

Where I'm at in the Pacific Northwest section, August is when our sectionals take place.  The 18 & over league will be played August 9-11 in Portland, and the 40 & over will be in Yakima August 23-25.  I've worked with a number of teams headed to Sectionals to provide Estimated Dynamic NTRP Rating Team Reports on both their own team and their opponents to help them plan line ups and strategy.  These reports include the current Estimated Dynamic NTRP Rating for all team members as well as their record on the team and full listing of what players played on each court and how many times.

Team reports aren't limited to the Pacific Northwest Section though.  I've provided team reports for teams in other sections including Hawaii, Northern California, Southwest, Inter-Mountain, Texas, Missouri Valley, Southern, Eastern, and the Caribbean.  Using these reports, one team has already advanced to Nationals, and several others are on their way to Sectionals.

It's not too late to get team reports.  Contact me and I can generate reports for you too.

Tuesday, July 30, 2013

Estimated Dynamic NTRP Ratings for Washington D.C.

I posted a list of ratings for Tulsa earlier today, and I've now posted a list for Washington D.C.  Have a look.

Estimated Dynamic NTRP Ratings for Tulsa in the Missouri Valley Section of the USTA posted

I have added to the areas I've posted Estimated Dynamic NTRP Ratings lists for and it now includes Tulsa.

Other areas I'd previously posted lists for include Houston, Northwest Washington, and Southwest Washington.  I plan to add more lists soon, so please leave a comment to let me know which you'd like to see.

Monday, July 22, 2013

Another Estimated Dynamic NTRP Rating Team Report Customer Advances in Playoffs

Estimated Dynamic NTRP Rating Team Reports are a great way to get a deeper understanding of not only your team's strengths and stats, but also an opponent's when preparing to play them in the playoffs.  I've generated these reports for team captains that are just interested in their own team, but also a number that were headed to playoffs and wanted the details to help them plan line-ups.

I'm pleased to say that another customer of these reports has advanced in the playoffs, winning their District.  They were playing the best 2 out of 3 team matches head to head against the team from the other Area in their District and came out on top 2-1.

After winning the first team match, the team got more players involved and lost the second, but using the reports ran out their best line-up in the third and deciding match and won 4-1.  Here is how the ratings predicted the final match:

  • 1 Singles - A 2.96 beat a 2.73 6-3,6-3
  • 2 Singles - A 2.87 beat a 2.78 5-7,7-6,1-0
  • 1 Doubles - A 2.65/2.90 lost to a 2.75/2.90 5-7,6-3,1-0
  • 2 Doubles - A 2.88/2.81 beat a 2.82/2.61 6-1,4-6,1-0
  • 3 Doubles - A 2.74/2.73 beat a 2.95/2.62 7-5,6-3
My ratings picked the right winner in all the matches but court 3 doubles, and that was one where there was a big disparity on the losing team which can be exploited if the other team can just avoid the stronger player, so not a surprise that is where the "upset" was.

This team is now on to Sectionals.  Good luck!

Monday, July 15, 2013

Texas Early Start Ratings Are Available

The Pacific Northwest section early start ratings came out a week ago and Texas is another section that has early start ratings and they came out today.

I'll be doing some analysis so look for that in the next few days.

Saturday, July 13, 2013

We need a better way to follow USTA tournaments and playoffs

My team is fortunate to have made our local playoffs this weekend and have a bye into the semis today.  Our opponent was determined by a match played last night, but short of having driven 45 minutes to watch the match at 5:30 yesterday evening, the only way to find out the result is to check on TennisLink and hope the result gets posted.

And there is the issue.  I have to "hope" it gets posted in a timely fashion.  Unfortunately, it hasn't been yet at 8:00 AM the next morning, and this isn't uncommon from my experience with other USTA playoffs and tournaments.

I've suggested before, even contacting league coordinators directly, that there needs to be a better way to communicate results and other status from an event, but to my knowledge, nothing has changed.  In this world of social media, why can't one person at an event be designated to just tweet a few updates so participants and fans can easily follow what is going on and be able to show up to play or see a match at the right time?

If you agree, please let your league or section coordinator know and lets try to get this addressed.

Wednesday, July 3, 2013

2014 Pacific Northwest Early Start Ratings are out, how accurate are the Estimated Dynamic NTRP Ratings?

As I wrote about yesterday, in the Pacific Northwest Section of the USTA, we have Early Start Ratings and as expected they came out yesterday.  The can be found here.

With their release, it provides an opportunity to check my Estimated Dynamic NTRP Ratings as they should mirror and predict the bump ups/downs fairly closely.

I'm working on a more comprehensive analysis, but I did some spot checks based on feedback and questions from a few folks that had gotten individual or team reports in the past.

For one team I did a team report for, I predicted that 4 players were in line to be bumped up from 3.5 to 4.0 and indeed they were.  However, the team also had 3 more players that got bumped up that I didn't predict.  Looking closer, these 3 were the next 3 highest rated in my report and I had each one above 3.5 a few matches earlier and they'd dipped just below in their last match or two.  So certainly very close on these 3 "misses".

Another person I've done several individual reports for wrote me to let me know that he and a teammate had been moved up, but two others who had thought they might be weren't.  For these 4, my estimated were spot on agreeing with both bump ups and also agreeing the 2 that weren't shouldn't have been.

Then there was also another 2 that thought they'd be bumped down and were and I predicted these too.

Last, a friend had been getting periodic updates and expected to be bumped down and was and I predict this one correct.

For this sampling then, my ratings went 11 for 14 on predicting the bumps.  And the three that missed did so by just a few hundredths so not far off at all.

Stay tuned for more.

Tuesday, July 2, 2013

2013 Early Start Ratings for 2014 Early Start Leagues for the Pacific Northwest

At this time of year in the Pacific Northwest, USTA League players look forward to the Early Start Ratings coming out.  I've been told by one of the mixed doubles coordinators that they should be out in early July so it could be any day now.

What are Early Start Ratings?  Basically, they are ratings that are used to determine the level players should play at for Early Start Leagues.  What is an Early Start League?  It is a league that starts play before the USTA year begins (normal year is roughly November thru October).

The idea is that if a league starts play before year-end ratings are out, for example a 2014 mixed doubles league that starts in September, players that are well on their way to being bumped up or bumped down at year end should play in the Early Start League using their new rating instead of their old rating.  The Early Start Rating is basically a snapshot of the Dynamic Rating at a point in time.

How about an example.

Say a player is a 3.5 in 2012 year-end ratings and has had a great 2013 adult league season and improved their Dynamic Rating to 3.7.  This is well into the range for a 4.0 and indicates they are likely to be bumped up at the end of the year.  Because the 2014 mixed and senior leagues start play before 2013 year-end ratings come out, it wouldn't be fair to let this player enter those leagues and play well into 2014 as a 3.5.  So, because their Dynamic Rating at the time Early Start Ratings come out is 3.7, they are given an Early Start Rating of 4.0 and must play 2014 mixed and senior leagues as a 4.0.

Correspondingly, a player may have their rating go down and receive an Early Start Rating down a level and be permitted to play the Early Start Leagues at that level.

Note that an Early Start Rating does not guarantee that a player will stay bumped up or down in the year-end ratings.  Year-end ratings will include additional matches played after Early Start Ratings come out and also incorporate benchmark calculations which can move a rating up or down.

So stay tuned for the ratings to come out.  And if you want to know before or after why your rating ended up where it is, an Estimated Dynamic NTRP Report is a great way to find out.  Contact me to learn more.

Update: I just found out that the early start ratings should be out this evening (7/2) and will include matches played through 6/25.