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.

Some sections aren't sending teams to Nationals at some levels

The USTA has been publishing schedules for 2021 USTA League Nationals and they've gone through a few iterations, seemingly as teams from some sections have elected not to go.

I wrote a few days ago how Nationals work, and as I write this, it appears:

• 18 & Over 2.5W - 15 teams, Hawaii and Northern not sending teams
• 18 & Over 3.0W - 17 teams
• 18 & Over 3.0M - 15 teams, Hawaii and SoCal not sending teams
• 18 & Over 3.5W - 17 teams
• 18 & Over 3.5M - 16 teams, Hawaii not sending a team
• 18 & Over 4.0W - 16 teams, Caribbean not sending a team
• 18 & Over 4.0M - 17 teams
• 18 & Over 4.5W - 15 teams, Caribbean and Hawaii are not sending teams, Hawaii was originally listed as sending a team
• 18 & Over 4.5M - 16 teams, Caribbean is not sending a team
• 18 & Over 5.0W - 11 teams, Caribbean, Hawaii, Florida, New England, Northern, and Southwest not sending teams
• 18 & Over 5.0M - 12 teams, Caribbean, Hawaii, Middle States, Northern, and SoCal not sending teams
• 40 & Over 3.0W - 16 teams, Hawaii not sending a team
• 40 & Over 3.0M - 15 teams, Hawaii and Northern not sending teams
• 40 & Over 3.5W - 17 teams
• 40 & Over 3.5M - 16 teams, Hawaii not sending a team
• 40 & Over 4.0W - 17 teams
• 40 & Over 4.0M - 16 teams, Hawaii is not sending a team but originally was
• 40 & Over 4.5W - 16 teams, Caribbean not sending a team
• 40 & Over 4.5M - 17 teams

Hawaii is not sending 10 teams, no big surprise given the travel required, Caribbean similarly is not sending six teams, and Northern isn't sending four teams.  In some cases the teams not being sent are at the top and bottom of the levels where the smaller section may not have critical mass for leagues and simply doesn't have teams as well.

Such are the challenges of having championships for a country with locations so far apart and population differences.  Still, it looks like a good turnout all things considered and a great comeback after no Nationals last year.

A refresher on how 2021 USTA League Nationals work

USTA League Nationals starts two weeks from today and as we approach it, I thought it would be a good idea to write a refresher on how it works.  See this for a refresher I wrote in 2019.

Teams qualify from the 17 sections by playing in local leagues, and advancing through one or more of local, district, and state playoffs to make it to Sectionals, where the winner qualifies for Nationals.  Thus, there will be up to 17 teams for each division/gender/level.

I say "up to" because at some levels, typically at the ends of the rating ranges, e.g. 2.5 and 5.0, sometimes a section might not have enough interest or participation and won't send a team.  Or once in awhile, a team that wins Sectionals and qualifies will elect to not go, and decides late enough that the runner up can't go either.  So sometimes there won't be 17 teams.

Now, 17 teams is kind of an odd number when it comes to having multiple same sized flights.  For years, until 2018, the USTA split the 17 teams into four flights, three with four teams and one with five teams.  The teams played round-robin against the other teams in their flight, and the flight winner advanced to the semi-finals.  The three 4-team flights would have three matches for each team, the 5-team flight would have four.

The semi-finalists would then play a normal single elimination bracket with the two winners facing off in a final for the championship, and the losers playing for 3rd place.

It was always a little awkward with the 17 teams, being in the 5-team flight meant you got to play an additional match and get more tennis in or get more players in a match, but you also had to play an additional match increasing the risk of a loss and perhaps putting the flight winner at a disadvantage with an extra match tiring folks out.

Now, when one section didn't send a team, there was a nice round 16 teams that were nicely split into four flights of four teams each.  But if more than one section didn't send a team, you got awkward situations again.

In 2018, the USTA introduced a new format for Nationals: Unflighted Round-Robin.  In this format, the 17 teams are all in one flight, but clearly they couldn't all play each other, so instead each team plays a random four other teams.  The semi-finalists are determined by standings in this single flight, the top-4 advancing.

This solves the problem of an uneven number of matches nicely regardless of the number of teams, but it introduced some other pros and cons:

• Pros
• Every team gets a consistent four matches.
• Unlike with the four flights where an early loss might eliminate you, there are ways to make the semis with a loss as it is pretty common that one or more 3-1 teams finish in or tie for a top-4 spot.
• Cons
• It is possible for five (or more) teams to finish 4-0 and one would be sent home.
• While four teams finishing 4-0 is possible, it is not assured or even the most likely scenario, meaning teams will be tied for a semi-final spot and the standings tie-breakers come into play that are arguably flawed and may advance the "wrong" team.
• The random schedule typically results in some teams with far easier/harder schedules which influence who makes the semis since they are all being compared with each other.

I wrote a lot on the topic three years ago, issues with the tie-breakers did crop up a few times, and I even submitted a regulation change proposal to fix the tie-breakers, but alas the format remains as-is for 2021.

The format was used in 2018 and 2019 and would have been in 2020 but Nationals were not held, so this will be the third year it is used.

While unflighted round-robin isn't new for 2021, this will be the first year that the 40 & Over division uses the 4-court format at Nationals.  This format was introduced for 2020 but since Nationals were not held, 2021 will be the first time it is used for a National Championship.  Stay tuned for a write-up on this.

To all those teams going to Nationals, good luck!

The first 2021 USTA Nationals event is just 16 days away!

Are you ready for USTA League Nationals?  I hope so, because the first matches will be played in just 16 days on October 1st in Arizona and Oklahoma City with the 18 & Over 3.0, 3.5, and 5.0 levels all playing.

With the events so close, you'd hope the USTA would be publishing schedules, teams, and other information soon, and they finally are.  They began sending schedules out to captains last week, but the Nationals site wasn't updated until the past day or so when the "Event Schedule" links went live for all of the 18 & Over and 40 & Over events.  The 55 & Over and Mixed events all still say coming soon.

So, if you are going, or just interested in the match-ups, you can now see which sections play which other sections for all of the 18/40 events.  Alas, these event schedules don't show the actual teams, those will show up on TennisLink, and as of this morning, only a few Tri-Level and 55 & Over events showed up there, and with just a few teams, but checking right now, more are showing up, specially 18 & Over 2.5W, 3.0, and 5.0 show up, although I did not check each for completeness.  Regardless, things are ramping up!

I have a backlog of report requests waiting for the teams to be identified, so I'll have a busy few days coming up, but that doesn't mean it is too late to request reports as I can do reports for teams to help them scout and plan their line-ups right up to the start of, and even during, the events.

Reports include flight reports giving a great summary of the teams and how they compare and run their line-ups out, team reports with details on each player and all the doubles pairings, and a simulation report predicting what records each team is most likely to have through round-robin play.

I already worked with double digits of teams that won Sectionals and are headed to Nationals, contact me if you want to add your team to those going to Nationals similarly equipped!

USTA National begins to publish the schedule and match-ups for USTA League Nationals

It is hard to believe, but USTA League Nationals are less than four weeks away!  We've made it through local, district, and sectional league play in most sections with various COVID-19 restrictions and if all goes well, we'll have Nationals this year.

As we approach the first Nationals the first weekend of October, the USTA is beginning to publish the schedule and match-ups for round-robin play.  I have not yet seen it show up on the Nationals page, there is a US Open going on, but e-mails are going out to captains with the information.

Have you gotten an e-mail yet?  What do you think of the schedule you drew?

As always, stay tuned for a sequence of articles here regarding Nationals including the format, previews, and predictions.  If you are interested in anything in particular, leave a comment and I'll see what I can do.

And for those that want to do scouting of opponents and plan line-ups, I do offer my full suite of flight, team, and simulation reports, so let me know if you are interested in any of those.

Good luck to all those going!