Age Development in Women's Singles
In a previous post, we showed the vector fields for the age development of strength values of all players. Here we will take a look at the developments for selected women’s singles players and compare their developments to the developments for all players.
Methodology
For how the vector fields, that serve as a background in the following plots, were calculated, see the aformentioned post about age developments. In short they show the averaged development for players who shared a similar strength at certain ages.
Then for the selected players, we will calculate their simulated strength at all their birthdays and if the player fulfills the criteria of having at least ten matches used for the strength and at least one match within the last year, the data point is included. The players development is then added to the vector field in a different color. The legend will display the player’s name as well as his or her birthday.
As we only use rankings since the beginning of 2010, older players’ young years will be missing from the plots. Also for players who are still active, the later years will be missing.
Also in the vector plots, one arrow might correspond to only one entry, especially for the top players. Thus in the following plots, this arrow might be identical to the strength development of one the players in question, thus this player’s arrow will lie exactly on top of the arrow from the general plot.
Results
Wang Yihan, Li Xuerui, He Bingjiao and ChenYufei
Comparing these four Chinese players, three of the curves look quite similar. Only He Bingjiao is a bit lower, but her strength value in the latest monthly world rankings has increased to about 22. Chen Yuei has overtaken her around the age of 19 to reach the very top with the other players. These peaked at ages of around 23 to 24.
Li Xuerui reached the highest value in the whole dataset with a value of about 25 at her 24th birthday. For her there is also a gap visible after her injury at the Rio Olympics, that left her out of competition for more than a year. We can see that after her return she could not reach her former level.
Saina Nehwal and Pusarla Venkata Sindhu
It was already remarked in the blog post A Look at the Future of Indian Women’s Singles that the developments of these two top Indian women’s singles players look very similar. Both were at their highest level between the ages of 22 and 27. It has to be seen how P.V. Sindhu strength value will develop in the future.
Carolina Marin and Tai Tzu Ying
Here we see two players of similar age. Tai Tzu Ying started at a higher level in her teenage years, while up to the age of 22, Carolina Marin’s improvement has almost always been greater. Thus their strength values met at their respective 22nd birthdays. The next three years however, Tai Tzu Ying’s strength value peaked, while Marin’s value stagnated. But from the age of 26 on Marin has overtaken Tai Tzu Ying. The difference is quite small though.
Nozomi Okuhara and Akane Yamaguchi
Comparing these two Japanese players, it is obvious that Akane Yamaguchi had a quite bad year between her 18th and 19th birthday, while Nozomi Okuhara had a brilliant year between her 20th and 21st birthday. Apart from these outliers, the curves look quite similar with small advantages for Okuhara.
Ratchanok Inthanon and An Se Young
Finally two players who were at the top level at a very young age.
We can see that Ratchanok Inthanon was probably the best 15-, 16- and 17 year-old there ever was. An Se Young could catch up and overtake her after the 19th birthday. Being the best 20 year-old, she has good chances to stay at the top level for a long period of time.
Conclusion
We can see some differences in the developments for these selected players. However, at least in this selection, there are no players who represent different categories as clearly as in the men’s singles. For example no one could serve as an example for late bloomers. Ratchanok is probably closest to representing a group, the group of players who were exceptional as teenagers but then failed to convert this into success at the senior level. She however was constistently rated at values of about 21, so she definitly reached world-class levels.