Results from the first weekend of 2021 USTA League Nationals - How did the predictions do?

The first weekend of Nationals is in the books and there were tight matches, some expected results, and some surprises as well.  And I'm pleased to say two teams I did reports for made the semis!  Well done teams.

Here is a summary of who won and how my simulations and previews did predicting things in the first 18 & Over events.

The 3.0 women had New England, Southern, and Intermountain all advance with 4-0 records, and Midwest beat out PNW and Mid-Atlantic on the tie-breakers for the last spot with a 3-1 record.  These four were all in the top-5 of who the simulation projected would advance, so nearly nailed this one.  New England won their semi over Midwest 3-2 and Intermountain won theirs 4-1, and then New England won the final 3-2, four matches went to match tie-breaks, to become the champs.

The 3.0 men had Caribbean, Intermountain, Southern, and Pacific Northwest all advance as 4-0 teams, no one losing more than three courts.  Intermountain, Caribbean, and Southern were expected to be there all being in my top-5 to advance, but PNW surprised a bit moving up from a projected 8th.  PNW and Intermountain faced off in the final after 3-2 wins where Intermountain took the title winning 5-0.

The 3.5 women also had four 4-0 teams advance in Intermountain, Florida, Southern Cal, and Missouri Valley advance.  Three of these were in my top-4 and SoCal was expected to be in the 6-way tie at 3-1 for 2nd/3rd so again nearly nailed it.  Intermountain and Florida faced off in the final after 4-1 wins, where Florida won 4-1 to take the title.

The 3.5 men had a 6-way tie for 2nd thru 7th, just Midwest advancing with a 4-0 record, and Southwest, Missouri Valley, and Mid-Atlantic won the courts tie-breakers to advance.  Three of these teams were in the simulation's top-6, Southwest stepped up from a projected 8th to make the semis, so again a pretty good showing with the predictions.  The final had Midwest face off against Southwest where Midwest won 4-1 for the title.

The 5.0 women had Texas and Mid-Atlantic at 4-0 and Intermountain and Missouri Valley at 3-1 all advance.  All four of these teams were in the simulation's top-6, so another good showing.  Texas and Mid-Atlantic faced off in the final where Mid-Atlantic took it 3-0.

The 5.0 men had Southern advance with a 4-0 record, then Pacific Northwest, Mid-Atlantic, and Northern California advanced out of the 4-way tie at 3-1.  Three of these were all in the simulation's top-5 so again nearly nailed it.  NorCal and Mid-Atlantic played in the final where Mid-Atlantic won 2-1.

Congratulations to all who advanced and played, and especially those that came out on top.

And I'm please to see the simulations do so well predicting things with every team that advanced being projected to be 6th or better except for one and that was 8th.

Another weekend of Nationals is coming up, stay tuned for more previews and predictions.

Update after day 1 of 2021 USTA League Nationals

Day 1 of this year's Nationals are in the books, and here are some notes and observations.

For the 3.0 women, I didn't get a simulation published, but a 6-way tie at 3-1 was projected with New England, Southern, Midwest, MoValley, Intermountain, and PNW, and after one day just MoValley under-performed going 0-2, and now New England, Intermountain, and Southern are projected to go 4-0 with a 3-way tie at 3-1 with PNW, Midwest, and Mid-Atlantic vying for the spot.

The 3.0 men had Texas, Intermountain, NorCal, Carribean, and Southern all at 3-1 or better, and after day 1, the list has expanded to be Caribbean, Southern, Intermountain, PNW, Texas, Eastern, and Mid-Atlantic.  This one could be a tie-breaker fest.

The 3.5 women had eight teams at 3-1 or better, now it is seven with a 4-way tie at 3-1 with NorCal, MoValley, Midwest, and Socal.

The 3.5 men had seven teams projected at 3-1 or better, now there are five in MoValley, Florida, Midwest, Southwest, and Southern.

The 5.0 women had five teams projected at 3-1 or better and there are still five, but Texas has moved into the group replacing NorCal, joining Intermountain, Mid-Atlantic, MoValley, and PNW.

The 5.0 men had five teams projected to be tied at 3-1, but now the projection has NorCal slipping out of the 3-1 group with PNW, Southern, Mid-Atlantic, and Eastern remaining.

2021 USTA League Nationals starts today! Time to check the weather forecast

Today is the first day of the 2021 USTA League Nationals.  The 18 & Over division start things off with the 3.0 men and women in Oklahoma City, the 3.5 men and women in Surprise, AZ, and the 5.0 men and women in Phoenix.

As I write this Friday morning, matches should be underway in Oklahoma City, but oddly TennisLink does not yet show the schedule in the "Match Summary" tab.  The other levels do have the full schedules on TennisLink.  The PDF schedule for all has been available for awhile.  I'm sure they will get it fixed, but I wonder if there will be delays in posting results for the 3.0 event? [see update below]

I will be monitoring what goes on and will likely write about anything odd or interesting that comes up.

But something that is always interesting is the weather and its potential impact on play.

OKC's forecast is a little iffy, with thunderstorms moving in late today and rain lingering tomorrow morning, but otherwise appears to be ok.  Let's hope they get matches in today and there aren't delays tomorrow morning.

The Arizona weather is near perfect, if not slightly warm as highs will be in the low 90s with no chance of rain.

Good luck to all!

Update: The schedules for the 3.0 level are now on TennisLink.

Simulating 2021 USTA League Nationals - 18 & Over 5.0 Men

As I did in 2018 and 2019, I will be doing simulations of each Nationals to predict who the most likely four teams are to make the semi-finals, and also look at other interesting things that may occur.  In the two years I've done this, the simulations have done a pretty good job predicting who would advance to the semis including having all four teams predicted correctly several times.

Why do these simulations you ask?  The primary reason is that the format for USTA League Nationals is now a flight-less random round-robin where each team plays four other random opponents.  This introduces significant variations in schedule strength, the possibility of an undefeated team not making the top-4, and teams vying for the top-4 perhaps not having played head-to-head and unfortunate tie-breakers being used.  The simulations aim to educate folks on how it all works and look at what may happen.  Also see this write-up for some things to know about Nationals.

Nationals is just getting going this weekend, the 18 & Over 5.0 event being held in Phoenix Arizona.  Here is what the simulation says is likely to happen for the men's side of things.

As a reminder, my simulations are done using my Estimated Dynamic NTRP Ratings and looking at the average rating for the top group of players on each team, the actual schedule each team will play, and then doing a million simulations of the matches with some random variation in each team's expected result.

This event has just 12 teams and as such there is a schedule where there won't be more than four undefeated teams, less than 1% chance of four undefeated, and just a 6% chance of three.

That chance is 62%, that there will be a tie for the last spot (3-1 or 2-2) and it come down to tie-breakers.  The most likely size of the tie is a four at 34%, but five is very high at 25%, and three is 25% too.  The chances of larger ties diminish pretty quickly, but a 10-way tie is theoretically possible, but it appears a multi-way tie is a very high probability and it could be reasonably large.

Should there be a tie on team record, it comes down first to who has the best court record, then head-to-head (if applicable), then to who lost the fewest sets, then who lost the fewest games, and finally percent of games won.  There is a 26% chance it comes down to the sets lost tie-breaker, and there is a 62% chance that is between two teams and a decent 30% chance it is between three teams,  If the controversial tie-breakers are going to come into play, this is the likely spot.

The schedule strengths do vary a bit, the team with the easiest schedule having an opponent average of 4.78 while the team with the toughest schedule having an opponent average of 4.88.  This leads to an easier road for some teams than others, two of the predicted semi-finalists getting there due to an easier schedule.

So who is most likely to come out in the top-4?  Southern, NorCal, Eastern, and Mid-Atlantic are solid choices.  Pacific Northwest is lurking, and Texas , Intermountain, and Florida ready to step in.

For those interested, I offer a variety of reports to make Nationals more fun and help captains prepare.  I have a Simulation Report that has all of the details of the simulation including the average ratings for each team, each team's schedule strength, the most likely record for each team, and the chance of each possible record for each team.  I also offer reports to help teams scout opponents in more detail, both a Flight Report with full roster averages, top-8 averages and played by court averages for each team, as well as full Team Reports with detailed ratings for each rostered player and stats who who plays with who and on which court and how they do together.  Contact me if interested in any of these reports.

Simulating 2021 USTA League Nationals - 18 & Over 5.0 Women

As I did in 2018 and 2019, I will be doing simulations of each Nationals to predict who the most likely four teams are to make the semi-finals, and also look at other interesting things that may occur.  In the two years I've done this, the simulations have done a pretty good job predicting who would advance to the semis including having all four teams predicted correctly several times.

Why do these simulations you ask?  The primary reason is that the format for USTA League Nationals is now a flight-less random round-robin where each team plays four other random opponents.  This introduces significant variations in schedule strength, the possibility of an undefeated team not making the top-4, and teams vying for the top-4 perhaps not having played head-to-head and unfortunate tie-breakers being used.  The simulations aim to educate folks on how it all works and look at what may happen.  Also see this write-up for some things to know about Nationals.

Nationals is just getting going this weekend, the 18 & Over 5.0 event being held in Phoenix Arizona.  Here is what the simulation says is likely to happen for the women's side of things.

As a reminder, my simulations are done using my Estimated Dynamic NTRP Ratings and looking at the average rating for the top group of players on each team, the actual schedule each team will play, and then doing a million simulations of the matches with some random variation in each team's expected result.

This event has just 11 teams and as such there is a schedule where there won't be more than four undefeated teams, and in fact there is less than a 3% chance of three undefeated.

That chance is 62%, that there will be a tie for the last spot (3-1 or 2-2) and it come down to tie-breakers.  The most likely size of the tie is a four at 44%, but five is very high at 28%, and three is 22%.  The chances of larger ties diminish pretty quickly, but a 9-way tie is theoretically possible, but it appears a multi-way tie is a very high probability and it could be reasonably large.

Should there be a tie on team record, it comes down first to who has the best court record, then head-to-head (if applicable), then to who lost the fewest sets, then who lost the fewest games, and finally percent of games won.  There is a 27% chance it comes down to the sets lost tie-breaker, and there is a 60% chance that is between two teams and a decent 31% chance it is between three teams,  If the controversial tie-breakers are going to come into play, this is the likely spot.

The schedule strengths do vary a bit, the team with the easiest schedule having an opponent average of 4.71 while the team with the toughest schedule having an opponent average of 4.78.  This leads to an easier road for some teams than others, one of the predicted semi-finalists getting there due to an easier schedule.

So who is most likely to come out in the top-4?  Mid-Atlantic, Pacific Northwest, Missouri Valley, and NorCal are solid choices.  Intermountain is lurking, and Texas and Eastern are ready to step in.

For those interested, I offer a variety of reports to make Nationals more fun and help captains prepare.  I have a Simulation Report that has all of the details of the simulation including the average ratings for each team, each team's schedule strength, the most likely record for each team, and the chance of each possible record for each team.  I also offer reports to help teams scout opponents in more detail, both a Flight Report with full roster averages, top-8 averages and played by court averages for each team, as well as full Team Reports with detailed ratings for each rostered player and stats who who plays with who and on which court and how they do together.  Contact me if interested in any of these reports.

Simulating 2021 USTA League Nationals - 18 & Over 3.5 Men

As I did in 2018 and 2019, I will be doing simulations of each Nationals to predict who the most likely four teams are to make the semi-finals, and also look at other interesting things that may occur.  In the two years I've done this, the simulations have done a pretty good job predicting who would advance to the semis including having all four teams predicted correctly several times.

Why do these simulations you ask?  The primary reason is that the format for USTA League Nationals is now a flight-less random round-robin where each team plays four other random opponents.  This introduces significant variations in schedule strength, the possibility of an undefeated team not making the top-4, and teams vying for the top-4 perhaps not having played head-to-head and unfortunate tie-breakers being used.  The simulations aim to educate folks on how it all works and look at what may happen.  Also see this write-up for some things to know about Nationals.

Nationals is just getting going this weekend, the 18 & Over 3.5 event being held in Surprise Arizona.  Here is what the simulation says is likely to happen for the Men's side of things.

As a reminder, my simulations are done using my Estimated Dynamic NTRP Ratings and looking at the average rating for the top group of players on each team, the actual schedule each team will play, and then doing a million simulations of the matches with some random variation in each team's expected result.

With 16 teams at the event the USTA never creates a schedule that can avoid more than four undefeated teams, and there is a  less than 1% chance of five undefeated.  There is only a 7% chance of four undefeated, so this means a very competitive event and a good chance of teams at 3-1 vying for the last advancing spot.

That chance is 89%, that there will be a tie for the last spot (4-0 or 3-1) and it come down to tie-breakers.  The most likely size of the tie is a 4 at 28%, but three is pretty high at 25%, and five is 22%.  The chances of larger ties diminish pretty quickly, but an 11-way tie is theoretically possible, but it appears a multi-way tie is a very high probability and it could be reasonably large.

Should there be a tie on team record, it comes down first to who has the best court record, then head-to-head (if applicable), then to who lost the fewest sets, then who lost the fewest games, and finally percent of games won.  There is a 27% chance it comes down to the sets lost tie-breaker, and there is a 68% chance that is between two teams and a decent 27% chance it is between three teams,  If the controversial tie-breakers are going to come into play, this is the likely spot.

The schedule strengths do vary a bit, the team with the easiest schedule having an opponent average of 3.51 while the team with the toughest schedule having an opponent average of 3.61.  This leads to an easier road for some teams than others, one of the predicted semi-finalists getting there due to an easier schedule.

So who is most likely to come out in the top-4?  Missouri Valley, Florida, NorCal, and Texas are solid choices, but a six-way tie is likely for 2nd thru 7th with Mid-Atlantic, Midwest, and Intermountain all having a greater than 50% chance of making the semis.

For those interested, I offer a variety of reports to make Nationals more fun and help captains prepare.  I have a Simulation Report that has all of the details of the simulation including the average ratings for each team, each team's schedule strength, the most likely record for each team, and the chance of each possible record for each team.  I also offer reports to help teams scout opponents in more detail, both a Flight Report with full roster averages, top-8 averages and played by court averages for each team, as well as full Team Reports with detailed ratings for each rostered player and stats who who plays with who and on which court and how they do together.  Contact me if interested in any of these reports.

Simulating 2021 USTA League Nationals - 18 & Over 3.5 Women

As I did in 2018 and 2019, I will be doing simulations of each Nationals to predict who the most likely four teams are to make the semi-finals, and also look at other interesting things that may occur.  In the two years I've done this, the simulations have done a pretty good job predicting who would advance to the semis including having all four teams predicted correctly several times.

Why do these simulations you ask?  The primary reason is that the format for USTA League Nationals is now a flight-less random round-robin where each team plays four other random opponents.  This introduces significant variations in schedule strength, the possibility of an undefeated team not making the top-4, and teams vying for the top-4 perhaps not having played head-to-head and unfortunate tie-breakers being used.  The simulations aim to educate folks on how it all works and look at what may happen.  Also see this write-up for some things to know about Nationals.

Nationals is just getting going this weekend, the 18 & Over 3.5 event being held in Surprise Arizona.  Here is what the simulation says is likely to happen for the Women's side of things.

As a reminder, my simulations are done using my Estimated Dynamic NTRP Ratings and looking at the average rating for the top group of players on each team, the actual schedule each team will play, and then doing a million simulations of the matches with some random variation in each team's expected result.

With 17 teams at the event the USTA never creates a schedule that can avoid more than four undefeated teams, and there is a  less than 2% chance of five undefeated.  There is a 15% chance of four undefeated, so this means a competitive event and a good chance of teams at 3-1 vying for the last advancing spot.

That chance is 84, that there will be a tie for the last spot (4-0 or 3-1) and it come down to tie-breakers.  The most likely size of the tie is a 4 at 28%, but five is pretty high at 26%, and three is 18%.  The chances of larger ties diminish pretty quickly, but an 11-way tie is theoretically possible, but it appears a multi-way tie is a very high probability and it could be reasonably large.

Should there be a tie on team record, it comes down first to who has the best court record, then head-to-head (if applicable), then to who lost the fewest sets, then who lost the fewest games, and finally percent of games won.  There is a 26% chance it comes down to the sets lost tie-breaker, and there is a 66% chance that is between two teams and a decent 28% chance it is between three teams,  If the controversial tie-breakers are going to come into play, this is the likely spot.

The schedule strengths do vary a bit, the team with the easiest schedule having an opponent average of 3.44 while the team with the toughest schedule having an opponent average of 3.57.  This leads to an easier road for some teams than others, one of the predicted semi-finalists getting there due to an easier schedule.

So who is most likely to come out in the top-4?  Florida, Intermountain, Texas, and Missouri Valley are solid choices, the first three likely to do it.  If another team finds their way into the mix, it is likely to be one of NorCal, Eastern, SoCal, or Midwest.

For those interested, I offer a variety of reports to make Nationals more fun and help captains prepare.  I have a Simulation Report that has all of the details of the simulation including the average ratings for each team, each team's schedule strength, the most likely record for each team, and the chance of each possible record for each team.  I also offer reports to help teams scout opponents in more detail, both a Flight Report with full roster averages, top-8 averages and played by court averages for each team, as well as full Team Reports with detailed ratings for each rostered player and stats who who plays with who and on which court and how they do together.  Contact me if interested in any of these reports.