ABOUT THE AUTHOR: MARTIN INGRAM – DATA SCIENTIST

Martin is passionate about good code and gaining insights from data with a particular interest in sports analytics. He completed a Bachelor Of Arts, Natural Sciences (Physical) at Cambridge before completing his Masters of Science, Computing Science.


In this preview, I use Glicko, a ratings system developed by Harvard Professor Mark Glickman, to predict this year’s Australian Open. Glicko is a generalisation of the Elo rating system which considers not just a player’s mean skill, but also the uncertainty about that skill.

This allows Glicko to deal more naturally with player absences than Elo: if a player is out of the competition for long periods, Glicko becomes more uncertain and makes larger adjustments to their rating when they return. If you would like to know more about Glicko, you can have a look at the original paper or a less technical write-up here.

Without further ado, here are the top 8 Glicko ratings for the men and women.


Men's

Player Mean Uncertainty
(1) Rafael Nadal* 2058 73
(2) Roger Federer 2032 67
(3) Novak Djokovic 2001 62
(4) Alexander Zverev 1887 58
(5) Kei Nishikori 1866 57
(6) Kevin Anderson 1840 57
(7) Marin Cilic 1817 62
(8) Andy Murray 1817 82

Perhaps surprisingly, Glicko puts Nadal on the top of the rankings. Looking purely at the results in his last tournaments in 2018, he looks strong: Nadal reached the semi-finals of the US Open (retired against del Potro), winning the Rogers Cup just before that. However, big doubts surround Nadal’s fitness this year. He underwent ankle surgery after the US Open and most recently withdrew from Brisbane. If he is fit, he is a strong contender, but given his injury issues, I do not consider him the favourite, hence the asterisk by his name.

Federer is given the second highest ranking, 26 points behind Nadal. After a stellar 2017, Federer’s 2018 season was more mixed and included some surprising losses, including one to John Millman at last year’s US Open. However, he had a fairly strong end to the last season, playing close matches against Djokovic at the Paris Masters and Zverev at the ATP World Tour Finals. Though it is only an exhibition, his form looked good at this year’s Hopman Cup, too, which he won with Belinda Bencic, making him one of the two favourites (together with Djokovic).

Novak Djokovic is ranked third by Glicko. After a lacklustre start, his second half of 2018 was very strong, earning him a Wimbledon and US Open title, among others. His last three tournaments suggest that he may not be unbeatable – losing to Khachanov in Paris, Zverev at the World Tour Finals, and, most recently, Bautista Agut in Doha – but those losses came in two finals and a semi-final, so he is certainly playing at a high level. At a rating of 2001, he is just 31 points behind Federer, which gives him a 46% probability of beating him.

Alexander Zverev, after some strong results last year, is ranked fourth by Glicko. However, with 1887 points, over 100 points separate him from Federer and Djokovic, which translates to a 35% win probability against Djokovic and 31% against Federer. In addition, he has struggled to translate his stellar results at Masters to results at Grand Slams, his best result being a quarter-final at the French Open last year. With victories over both Federer and Djokovic at last year’s World Tour Finals, he has shown that he can beat the best players, but he has yet to prove that he can do it at Grand Slams, too.

Nishikori and Anderson come in 5th and 6th. After many years of injury issues, Nishikori had some strong results recently, reaching the semi-finals of the US Open and winning Brisbane last week. Similarly, Anderson had a strong 2018, reaching the finals of Wimbledon. Like Nishikori, he has done well in a warm-up tournament, winning Chennai. Both Nishikori and Anderson appear to be in good form and may go far in the tournament. With ratings of 1866 and 1840, they are expected to beat Federer with 29% and 26% probability, respectively.

Marin Cilic is ranked 7th by Glicko. Last year’s Australian Open finalist, Cilic looked strong in 2018 until the US Open, where he lost in the quarter finals. After that, he struggled, losing early in Tokyo, Shanghai and Basel. He recently beat Anderson in the Kooyong exhibition, but doubts linger about a knee injury.

Finally, Andy Murray is ranked 8th. His skill uncertainty, at 82, is the highest of all players, reflecting his long absences due to injury. Since Wimbledon 2017, Murray has only played 8 tournaments, with his best results being a quarter final in Washington and Shenzhen last year. Most recently, he lost to Daniil Medvedev in the second round of Brisbane. Nevertheless, it is hard to count out a champion, and it will be interesting to see how he fares at the Australian Open.


Winners and Losers compared to last year

Among the current players ranked in the top 32 by Glicko, several players improved by over 100 points in the last year. The largest gains were made by Karen Khachanov (+168), Daniil Medvedev (+168) and Stefanos Tsitsipas (+163).

Aged just 22 (Medvedev, Khachanov) and 20 (Tsitsipas), these players are worth keeping an eye on. Similarly, Borna Coric (+135) and Alex de Minaur (+104) are young players on the rise. Martin Klizan (+148) and Kevin Anderson (+118) are the other players who gained more than 100 points over the last year.

The biggest loser compared to last year is – unsurprisingly – Andy Murray (-179). Stan Wawrinka (-113) dropped the second-most points, and Gael Monfils (-91), Grigor Dimitrov (-85) and Roger Federer (-74) also look somewhat worse than last year.


Women's

Player Mean Uncertainty
(1) Serena Williams 1932 88
(2) Simona Halep* 1880 77
(3) Angelique Kerber 1850 68
(4) Elina Svitolina 1839 70
(5) Karolina Pliskova 1836 63
(6) Arina Sabalenka 1835 63
(7) Ashleigh Barty 1829 65
(8) Caroline Wozniacki 1800 69

On the women’s side, 23-time Grand Slam winner Serena Williams comes in as the favourite with a Glicko rating of 1932. While ranked first, she also has the highest uncertainty of all players in the top 8, at 88, due to her playing only 7 tournaments since the Australian Open in 2017 (8 if Hopman Cup is included). She had some strong results last year, reaching the finals of both the US Open and Wimbledon, but failed to win a tournament. At the Hopman Cup, she won all three of her matches, suggesting that she appears to be physically fit.

Simona Halep comes in as second favourite, but big doubts surround her physical fitness. Since losing in the finals of Cincinnati, she lost four consecutive first round matches, most recently against Ash Barty in Sydney. She missed the end of last year due to a back surgery. As a result, despite her high Glicko rating, I have given her an asterisk.

Angelique Kerber is ranked third. With a Glicko rating of 1850, she is expected to have a 39% chance of beating Serena Williams. After beating Williams in last year’s Wimbledon final, she had poor results in the rest of 2018, failing to progress past the third round in any of the six tournaments she played. This year, she won all her matches at the Hopman Cup, and she is still in contention for the Sydney title.

After Kerber, four players are ranked within ten points of each other by Glicko: Elina Svitolina, Karolina Pliskova, Arina Sabalenka, and Ashleigh Barty. With around 1835 Glicko points, each of them is estimated to have roughly 37% probability of beating Williams.

Svitolina finished 2018 off strongly, winning the WTA Championships. At Grand Slams however, her performance has been subpar in the past; she has so far failed to progress past the quarter finals. Most recently, she lost her first-round match against Aliaksandra Sasnovich in Brisbane.

Pliskova, on the other hand, won Brisbane, suggesting she is on good form. Her results in Grand Slams last year were not stellar — she reached the quarter finals at the Australian Open, the third round at the French Open, fourth at Wimbledon, and quarter finals at the US Open – but she had some good tournament wins near the end of the year in Tokyo and Tianjin.

Sabalenka has had a great start to the year, winning Shenzhen, though she lost in the first round of Sydney (to Kvitova). Last year, highlights included wins in Wuhan and New Haven. Sabalenka is only 20 years old and may be worth looking out for. Her best result at a Grand Slam so far was a fourth round at last year’s US Open, however, so she has yet to prove herself at a Grand Slam.

Ashleigh Barty also started the year quite well, beating Halep and Ostapenko in Sydney. She had a good finish to last year, beating Kerber in Wuhan before losing in the semi-finals (to Sabalenka), and winning the WTA Elite tournament. Like Sabalenka and Svitolina, she has not yet made it past the 4th round at a Grand Slam, that result coming at last year’s US Open.

Finally, Caroline Wozniacki rounds out the top 8. After winning her long-awaited first Grand Slam at the Australian Open last year, she had a period of mixed results with some highlights, such as wins in Eastbourne and Beijing. Most recently, she lost to qualifier Bianca Vanessa Andreescu in Auckland, suggesting she may not yet be on the top of her game.


Winners and Losers compared to last year

Among the players ranked in the top 32 by Glicko, the three players with the biggest gains were Kiki Bertens (+186), Donna Vekic (+177), and Arina Sabalenka (+174).

Naomi Osaka, last year’s US Open winner, also made big strides, gaining 139 points, and Qiang Wang (+115), Camila Giorgi (+114), Lesia Tsurenko (+113), Anett Kontaveit (+106) and Angelique Kerber (+104) are also considerably stronger than they were last year.

On the other hand, Victoria Azarenka (-123), Serena Williams (-111), Garbine Muguruza (-72), Johanna Konta (-64) and Venus Williams (-59) lost some points over the last year.


Conclusions

In summary, the Australian Open 2019 promises to be an exciting tournament.

On the men’s side, Glicko rates the Big Three – Nadal, Djokovic and Federer – highest. Given Nadal’s injury woes, Djokovic and Federer are the most likely candidates to win. That said, players such as Zverev and Nishikori are not too far behind, and it will be interesting to see how far they go this year.

For the women, Glicko rates Serena Williams ahead, but Kerber and others are not too far behind, and young talents, such as Sabalenka, are on the rise. It will be interesting to see whether Sabalenka, Barty or Svitolina can go deep in the tournament.


Betting Strategy

 BACK – Roger Federer to win the Australian Open

 BACK – Serena Williams to win the Australian Open


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