Ranking Feature
Forecasting the US Open Juniors
by Dallas Oliver, 5 September 2015
Share: | |
| | |
|
|
All eyes in the tennis world are on New York and the US Open. And Sunday, the youngsters get in on the action. Qualifying is now done, and the US Open Junior Championships are ready to get underway. A score of talented American teenagers will try to win the most prestigious junior title on U.S. soil.
But how will the Americans do? Tennis Recruiting is dusting off its Heat Maps - and is ready to make some projections...
US Open Juniors Heat Maps
We use the Tennis Recruiting Power Ratings to produce Heat Maps for the US Open. You can view the Heat Maps by clicking here.
As in previous tournaments, these Heat Maps use our power ratings to show probabilities of how far we expect players to progress through the draws. (You can see power ratings and other information for all players in the Open by
clicking here.) We will update the heat maps after each round of the tournament to reflect the new probabilities based on actual wins and losses.
Explore the data by choosing genders using the top tabs - and then click on the top links and the table header columns for different sorts of the data.
Bold Predictions
We once again scattershoot across the heat maps, making predictions based on the probabilities...
- Americans with the best chances to advance to the semifinals:
- Top-four seeds with the toughest roads to the semifinals:
- Americans' chances to reach the finals or win the tournament:
- 65% chance that an American wins the Boys' championship.
- 39% chance that an American wins the Girls' championship.
- 82% chance of at least one American in the Boys' final.
- 62% chance of at least one American in the Girls' final.
- 33% chance of an all-American Boys' final.
- 15% chance of an all-American Girls' final.
- The first round of the tournament could prove exciting. We project nine upsets of seeded players in the first round of the junior events alone - and 17 upsets overall in the 64 matches. There are nine first-round matchups between closely-rated players where we believe the outcome is closer than 60%-40%.
These are just a few of the interesting predictions you can explore using different sorts of the data.
Frequently Asked Questions
Once again, we go to the mailbag - to answer three more common questions that we have received about our heat maps...
(1) I know that you do not rank international players on your website. Given that fact, how do you assess the performance of international players to generate heat maps for Grand Slam tournaments like the U.S. Open?
Although we do not display rankings for international players to the general public, we do have extensive information on international players. Results for all ITF junior events of all grades are included in our ranking system, and our system generates ratings for
all players in the system - including international players.
Note also that while the general public only has access to rankings of American juniors by graduation year, college coaches have the ability to create custom rank lists at Tennis Recruiting that include international players. Many coaches take advantage of these features.
(2) In your USTA Nationals Heat Maps, I noticed that the pre-tournament favorite to win the Boys 18s was Stefan Kozlov - with Francis Tiafoe not far behind. However, when those two players reached the finals, the heat map projected Tiafoe as the winner. Why did this happen? Do you re-rank the players during the tournament?
We do not re-rank during the tournament, and our pre-tournament ratings listed Tiafoe as the highest-rated player in the tournament. The real question is - why was Kozlov the pre-tournament favorite to win it all?
The answer is simple: our predictions take into account all potential opponents players may encounter on their way to the title. At the 18s event in Kalamazoo, the top half of the draw - that included Tiafoe - had slightly tougher players than the bottom half of the draw. Since Kozlov had the easier path, he was the pre-tournament favorite. However, once both young men advanced to the final, the head-to-head prediction went to the higher-rated Tiafoe.
(3) In general your heat maps look good, but every now and then one of your predictions just doesn't make sense to me. As a fan and spectator of the sport, I know one player has an edge over another, but you are calling it the other way. Why?
At the end of the day, our ranking system is only as good as the data it uses. In general, the longer the player record, the more accurate our ranking system becomes.
In the USTA Nationals 18s, some of the top competitors had very short records in our system because they had mostly stopped playing junior tournaments. Our system has not historically counted professional results from, say, the Futures tour. For these heat maps, we are not making any adjustments to what the computer spits out - and sometimes the computer simply does not have enough information to make the best decision.
Looking ahead, we have been taking steps to pull in more data to improve the quality of our rankings. We have already modified our procedures to use all ITF junior events (rather than our previous policy of only using ITF events on US soil or that have high American participation), and we are working towards including Futures events - and possibly ITA results as well. From what we have seen, we expect that expanding our data set in this way will only improve our rankings with longer records for all players.
So we expect our system to be even better next year - but overall we are satisfied with how well our system is performing today.
Follow Along!
So that's it. As the tournaments move along, we will update our estimates and predictions. Check out the upsets - and cheer on the players who move further than their power ratings might suggest. We expect there to be quite a few upsets - that's why they play the game!
Leave a Comment
More Ranking Articles
19-Sep-2017
Comparing Rating Algorithms
During the U.S. Open we posted information on social media about matchups involving American players - previewing matches by displaying rating and ranking differences and highlighting wins by underdogs. You might have noticed that the various rating systems often agreed on their favorites. But what about the close matches where they disagreed? Let's take a look ...
13-Jul-2016
Behind the Tennis Recruiting Rankings
This week marks the 569th consecutive week that Tennis Recruiting has
put out graduation-based rankings of American junior boys and girls.
Rankings are front and center on Tennis Recruiting, and people often ask
us how our rankings work. Today we describe our ranking system ...
19-May-2016
What Is An Upset?
Tennis Recruiting is a website that rates and ranks junior tennis
players. One of the questions we get most often from our users is,
"What exactly is an upset?" There are many possible
definitions of an upset - this article explores the question and
puts forward an answer.