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.
Australian Open Preview
In this article, I use ELO to preview the Australian Open 2017. In a recent analysis by Stephanie Kovalchik, ELO outperformed 11 other published models, predicting 70% of ATP matches correctly in 2014. The article will include a look at the top five favourites for the men and women, a review of how well ELO performed last year, as well as a list of some of the biggest winners and losers in terms of ELO over the last year.
The top five favourites on the ATP for 2017 in terms of ELO are:
- Novak Djokovic: 2460
- Andy Murray: 2404
- Roger Federer: 2312
- Rafael Nadal: 2212
- Kei Nishikori: 2209
ELO has two clear favourites: Andy Murray and Novak Djokovic. They also lead the ATP’s world rankings, but in ELO, Djokovic is still slightly ahead of Murray, while Murray has been ranked number one in the ATP’s ranking since reaching the Paris Masters final last November. Per ELO, if the two were to face each other today, the difference of 56 points means that Djokovic would be the 58% favourite to win.
Roger Federer and Rafael Nadal’s ELOs of 2312 and 2212 place them at positions three and four — much higher than their current ATP rankings of 16 and nine. This is because, in the absence of any playing activity, ELO predicts them to play as well as they did when they were last active, whereas the ATP ranking penalises them heavily for missing part of last year’s season (Federer last played at Wimbledon last July, Nadal at the Shanghai Masters last October). It remains to be seen whether they do indeed play to their previous standard after returning from injury.
At 2209 points, Kei Nishikori is only a hair behind Rafael Nadal. The gap to Andy Murray and Novak Djokovic is large even for Nadal and Nishikori, however. Against Djokovic, Nishikori and Nadal would have a 19% chance of winning; against Murray, the probability is about 25% for both.
How did ELO do last year? Last year, ELO picked the winner correctly in 81.0% of cases, which made it the best-predicted Grand Slam of the year (79.5% at the French Open, 76.6% at Wimbledon, 74.4% at the US Open). Eventual winner Novak Djokovic was the favourite (2508), followed by semi-finalist Roger Federer (2352), finalist Andy Murray (2288), Rafael Nadal (2249), who lost in the first round, and Stan Wawrinka (2193), who reached the fourth round. Although four of five favourites remain the same this year, Novak Djokovic, Roger Federer and Rafael Nadal have dropped around 40 points each, while Andy Murray has gained 116 points since then.
Big winners and losers compared to last year
Kyle Edmund (+327), Pablo Carreno Busta (+270), Alexander Zverev (+251) and Lucas Pouille (+238) all made huge gains last year. Three of these players are young: Zverev is 19, Pouille is 22, and Kyle Edmund is 21, which makes them players to watch out for in the future. Benoit Paire (-199), Lukas Rosol (-153) and David Ferrer (-121) did not have a good year.
On the women’s side, this year’s Australian Open is missing some of its top players. Maria Sharapova would be number two in terms of ELO, and Victoria Azarenka number three. Madison Keys and Petra Kvitova, both highly ranked, are also missing. Without them, the top five look as follows:
- Serena Williams: 2389
- Angelique Kerber: 2161
- Simona Halep: 2124
- Agnieszka Radwanska: 2097
- Johanna Konta: 2064
Here, too, ELO disagrees with the tour’s ranking. Serena Williams, number two in the WTA rankings and returning from a shoulder injury, towers above defending champion Angelique Kerber in ELO. At 2389 compared to 2161 points, she would be a 78.8% favourite against her closest competitor. Simona Halep and Agnieszka Radwanska follow, and Johanna Konta, having gained almost 200 points over the last year, comes in fifth.
How did ELO do for the WTA last year? Last year’s Australian Open was highly unpredictable, with ELO picking just 65.9% of matches correctly, compared to 71.2% at the French Open, 71.8% at Wimbledon, and 76.0% at the US Open. Finalist Serena Williams was the favourite last year, too (2447), followed by quarter finalists Maria Sharapova (2248), Victoria Azarenka (2202), first-round loser Simona Halep (2115), and fourth-round loser Belinda Bencic (2108). Eventual winner Angelique Kerber was rated 2092.
Big winners and losers compared to last year
Viktorija Golubic (+223), Shuai Zhang (+204), Laura Siegemund (+196), Naomi Osaka (+195) and Johanna Konta (+193) all made big gains last year. Naomi Osaka is just 19 years old, making her a player to look out for. Anna Schmiedlova had a terrible year (-258), as did Belinda Bencic (-236), Teliana Pereira (-175), and Alison van Uytvanck (-163).
ELO predicts Andy Murray or Novak Djokovic to be the likely winners on the men’s side, and Serena Williams on the women’s side. Although Williams’ edge in ELO is large, it remains to be seen whether she has recovered from her injury; if not, Kerber, Halep and Radwanska are ranked quite closely together, giving them all a good chance to win the title.
On the men’s side, Roger Federer and Rafael Nadal are highly rated in ELO but returning from injury, casting some doubt on their performance. If they do not perform as well as expected, it would make Murray and Djokovic even more likely to win their first or seventh Australian Open title, respectively.