Sunday, February 7, 2016

In what month are the most USTA League matches played? Interesting tennis league stats

It is early in the 2016 calendar year, but I thought it would be interesting to take a look at how many USTA League matches were played in each month of the 2015 calendar year.

The below chart shows the number of team matches in the Women's and Men's 18 & over, 40 & over, and 55 & over leagues during last year.



The chart isn't terribly surprising as most areas have leagues in the Spring and March thru June are the busiest months for the main leagues.  But there is still quite a bit of play in January and February, probably in leagues where there is indoor play or the South, and July in areas where leagues are finishing up.

If 2016 follows this trend, we are now nearing the meat of the league season.  Have fun getting out on the courts and playing!

Friday, February 5, 2016

PNW Seattle area 2016 40 & over schedules are out

For those in the Seattle area that will be playing in the 2016 40 & over league, the schedules have been published and play begins as early at February 19.

The 18 & over league started in early January, and some teams are well into their seasons with more than half their matches completed already.  So the season can go quick!

With just two weeks before matches start, get those players signed up, scout those opponents, and plan those line-ups.  It should be a fun season!

Thursday, February 4, 2016

How do Roger Federer's 2004 through 2007 seasons compare to Novak's 2011 and 2015?

I took a look at what are considered to be Novak Djokovic's two best seasons (2011 and 2015) compare using an Estimated Dynamic NTRP Rating Report chart, so next up is Roger Federer's 2004 through 2007 run.

First, 2004.


He was well over 7.0 early in the year with consistently high results at the Australian Open, then hung around 7.0 much of the rest of the year but dipped with the Cincinnati and Olympics losses, then had some closer than expected wins in Bangkok and the Masters Cup to finish just under 7.0.  The average dynamic rating for the year was 7.00.

Next, 2005.


Arguably his best year record wise, 2015 did have him over 7.0 more consistently with high points around/over 7.1 at the majors and Indian Wells.  He dipped late again though with closer than expected matches in Bangkok and the Masters Cup again.  The average for the year was his high of 7.01.

Next, 2006.


This year looks similar to 2005 with some similar peaks, getting almost 7.2 at Wimbledon, and again finishing just under 7.0.  The average for this year was 6.99.

Last, 2007.


This year does not have the same peaks, but he hung right around 7.0 and managed to finish the year just over at 7.02.  But the average for the year was the low of this four year run at 6.97 as the same peaks weren't there.

Comparing to Novak's 2011 and 2015, they are very similar, perhaps Fed's 2005 having higher peaks, but Novak's 2011 being more consistent.  Those charts here for comparison.

Novak 2011.


His average of 7.04 is his high and a testament to his consistency.

And Novak 2015.


This average was just 6.95, his 2013 and 2014 actually having higher averages at 6.98 and 6.96.

What other seasons do you considered to be some of the best ever?

How does Novak's 2015 season compare to his 2011 season?

Novak Djokovic had a fantastic 2015 going 83-6 on the year including 27-1 in the Grand Slams.  But he had a fantastic 2011 as well, so since I'm now calculating Estimated Dynamic NTRP ratings for ATP matches, I thought it would be interesting to compare the charts for each year.

Here is 2011.


Clearly a strong year with a rating over 7.0 much of the year, but he didn't finish strong with a couple losses to Ferrer and Tipsarevic at the Tour Finals and some other close wins against weaker opponents late in the year and a loss to Nishikori.

Here is 2015.


While he finished the year strong, and was over 7.0 several times during the year, he was not as far over 7.0 in 2015 as he was in 2011, nor was he as consistently over 7.0.

Since the data is connected, the relative ratings between years should have some meaning, and this would seem to indicate that perhaps his 2011 was stronger than 2015 through the majors, but just slipped a bit at the end.

Since Novak was generating higher ratings in 2011 with a similar record, one could perhaps come to the conclusion that the opponents were not as consistently strong.  There are many variables with draws and who he plays in early rounds, or if seeds are upset early and Novak doesn't have to play them late, that can influence this too, but with this many matches played, this data at least would seem to support the notion that 2015 had a slightly weaker top-50 to top-100 than 2011 did.

Wednesday, February 3, 2016

What if Novak Djokovic were to get an Estimated Dynamic NTRP Rating Report?

I am now calculating what  Estimated Dynamic NTRP rating ATP and WTA pros would have if the algorithm was used on their matches.  After seeing the top-20 lists for the men and women, the natural next question is what would an Estimated Dynamic NTRP Rating Report look for a pro?

To start, here is what Novak Djokovic's would be for 2015.

Estimated Dynamic Rating: 7.07
Match Record: 83-6
Best Match Result: 7.27 on 8/31/15
Worst Match Result: 6.66 on 3/12/15
Highest Estimated Dynamic Rating: 7.12 on 6/29/15
Lowest Estimated Dynamic Rating: 6.74 on 3/12/15


In the chart, the matches at the Grand Slams have a G on the match rating and Masters tournaments have an M.  You can click on the image to see a larger version.

Novak's rating actually moved up and down a fair amount during the year.  He started the year at 7.06 coming off his win at the 2014 Tour Finals and he was still around 7.0 after winning the Aussie Open, but it dropped reached a low point after his close wins over Ramos and Isner at Indian Wells, which followed the loss to Federer in Dubai and a closer than expected Davis Cup win.

His rating went back up after winning Indian Wells and Miami, then went up to 7.07 in getting to the final of the French Open and then was still at 7.01 after winning Wimbledon.  He dropped some in playing Canada and Cincinnati, then had his highest match rating of the year in beating Cilic at the US Open.

The Fall season found him staying right around 7.0 until the semi and final at the Tour Finals got him over 7.0 again.

Clearly, an 83-6 record and 89 matches played is not similar to most USTA League players, but having some up and down matches is pretty common, especially those that play a lot of matches.  A range of 0.38 from low to high dynamic rating is more than most have, but most don't play this many matches either.

What do you think?

Estimated Dynamic NTRP Ratings for the WTA - How much higher rated is Sharapova than you?

I wrote yesterday about how the players on the ATP tour would be rated if the USTA's NTRP algorithm were to be used to calculate dynamic ratings from their matches.  Today, it is time to take a first look at the WTA players.

All the same caveats I mentioned before apply again.  And again, I scaled things so that the top-400 players would be considered 6.5 or higher.

So here are the WTA top-20 through the end of 2015.

RankNameRating
1Maria Sharapova6.96
2Garbine Muguruza6.89
3Serena Williams6.87
4Petra Kvitova6.82
5Simona Halep6.79
6Karolina Pliskova6.77
7Madison Keys6.74
8Karin Knapp6.70
9Caroline Garcia6.67
10Sabine Lisicki6.63
11Mirjana Lucic6.62
12Shuai Peng6.60
13Olga Govortsova6.60
14Louisa Chirico6.59
15Mona Barthel6.58
16Lesia Tsurenko6.58
17Denisa Allertova6.57
18Flavia Pennetta6.57
19Martina Hingis6.54
20Lucie Safarova6.53

Unlike the men where Djokovic was #1, Serena is not #1 but is instead #3 behind Sharapova and Muguruza.  This is because Serena had several closer than expected wins at the US Open and then the loss to Vinci, plus she didn't play the rest of the year while the others did play more and so had a chance to improve their ratings and not lose to Serena.  It will be interesting to see how this changes when I include the Australian Open.

The women are quite a bit closer grouped at the top than the men, although there is nearly a 0.5 drop from #1 to #20 which is similar to the men.

Stay tuned for more.

Tuesday, February 2, 2016

Estimated Dynamic NTRP Ratings for the ATP - How much higher rated is Novak than you?

I've toyed with calculating my Estimated Dynamic NTRP Ratings for professional tennis in the past, calculating ratings for just the 2014 men and women at the Australian Open a few years ago.  But my roots in calculating ratings for professional tennis go back to my teen years when I was calculating ratings for players from just their play at the Grand Slams.  But I digress.

More to the present, I am now calculating what ATP player's dynamic NTRP ratings would be from their play in ATP (main draw and qualies), Challenger, and Futures events going back a number of years.  Given the differences between league play and tournament play at the professional level, I would not say these ratings are perfect by any stretch, but they are interesting to look at.

The ratings below are a little preliminary, I'm still fine tuning things, but wanted to share some initial data right away for people to see and comment on.

Before we look at some ratings, a few caveats.

First, these ratings are just from singles results, no doubles matches are included.

Second, the relative difference between players listed is correct/accurate, but since this set of data is not connected to league players, the difference between ratings I calculate from league play and these is a guess.  What I did was to try to ensure that the top-400 or so were considered 6.5 or higher since the USTA guidelines state a 6.5 or 7.0 is considered world-class.

Third, the dynamic NTRP algorithm is very biased towards your most recent results.  So a high rated player that has had a couple unexpected losses due to injury, playing their worst surface, etc. may have a lower rating than you'd expect.  Similarly someone who has pulled one of those upsets or is playing on their best surface may be rated higher than expected.

Fourth, these ratings include results through the end of 2015, but do not include the Australian Open or other January tournaments.

With that said, on to the ratings!  Here are the current top-20.

RankNameRating
1Novak Djokovic7.07
2Roger Federer6.94
3Rafael Nadal6.85
4Andy Murray6.78
5Stanislas Wawrinka6.71
6Tomas Berdych6.70
7David Ferrer6.69
8Marcos Baghdatis6.68
9Kei Nishikori6.66
10Marin Cilic6.64
11Hyeon Chung6.63
12Steve Johnson6.63
13Joao Sousa6.62
14John Isner6.61
15Richard Gasquet6.60
16Jack Sock6.60
17Milos Raonic6.60
18Gilles Simon6.59
19Roberto Bautista Agut6.59
20Jo Wilfried Tsonga6.58

No surprise who is rated the highest, and Novak is #1 is by a pretty healthy margin of 0.13 based in part to Novak's win in the final at the Tour finals.  Federer and Nadal are next on the strength of their Tour Finals final/semi, but there is a 0.09 gap between them, another 0.07 to Murray, and 0.07 again to Wawrinka.  After that it does get a lot closer.

It is surising to see Baghdatis and Chung so high, but Chung did have some good results to end 2015 winning a Challenger and making the quarters at Shenzhen playing Cilic close, and while not included in the above he beat Groth in straights and played Cilic very close again in Brisbane before a respectable, albeit straight sets, loss to Novak at the Aussie Open.  Baghdatis had a run to the semis in Stockholm to end his 2015.

By the scale set by the USTA, Novak would actually be a "7.5" while the rest shown would be 7.0s.  Again, this is somewhat arbitrary given where I starting things out.  But the gap between players is representative of the algorithm and you see there is nearly a full level (0.5) between #1 and #20 which I would not have expected.  There is just 0.13 between #5 and #20 though which shows the separation of the top-4 from those behind.

It will be interesting to see how these change after the Australian Open and other January events are incorporated.  Because of the third caveat above, players can move up or down a fair amount with a few better or worse than expected results, see Baghdatis and Chung above.

Stay tuned for more.