In my most recent piece for The Economist, I used a metric called Excitement Index (EI) to consider the implications of shortening singles matches to a format like the no-ad, super-tiebreak rules used for doubles. In my simulations, the shorter format didn’t fare well: The most gripping contests are often the longest ones, and the full-length third set is frequently the best part.
I used data from ATP tournaments in that piece, and several readers have asked how women’s matches score on the EI scale. Many matches from the 2016 season rate extremely highly, while some players we tend to think of as exciting fail to register among the best by this metric. I’ll share some of the results in a moment.
First, a quick overview of EI. We can calculate the probability that each player will win a match at any point in the contest, and using those numbers, it’s possible to determine the leverage of every point–that is, the difference between a player’s odds if she wins the next point and her odds if she loses it. At 40-0, down a break in the first set, that leverage is very low: less than 2%. In a tight third-set tiebreak, leverage can climb as high as 25%. The average point is around 5% to 6%, and as long as neither player has a substantial lead, points at 30-30 or later are higher.
EI is calculated by averaging the leverage of every point in the match. The more high-leverage points, the higher the EI. To make the results a bit more viewer-friendly, I multiply the average leverage by 1,000, so if the typical point has the potential for a 5% (0.05) swing, the EI is 50. The most boring matches, like Garbine Muguruza‘s 6-1 6-0 dismantling of Ekaterina Makarova in Rome, rate below 25. The most exciting will occasionally top 100, and the average WTA match this year scored a 53.7. By comparison, the average ATP match this year rated at 48.9.
Of course, the number and magnitude of crucial moments isn’t the only thing that can make a tennis match “exciting.” Finals tend to be more gripping than first-round tilts, long rallies and daring net play are more watchable than error-riddled ballbashing, and Fed Cup rubbers feature crowds that can make the warmup feel like a third-set tiebreak. When news outlets make their “Best Matches of 2016” lists, they’ll surely take some of those other factors into account. EI takes a narrower view, and it is able to show us which matches, independent of context, offered the most pressure-packed tennis.
Here are the top ten matches of the 2016 WTA season, ranked by EI:
Tournament Match Score EI Charleston Lucic/Mladenovic 4-6 6-4 7-6(13) 109.9 Wimbledon Cibulkova/Radwanska 6-3 5-7 9-7 105.0 Wimbledon Safarova/Cepelova 4-6 6-1 12-10 101.7 Kuala Lumpur Nara/Hantuchova 6-4 6-7(4) 7-6(10) 100.2 Brisbane CSN/Lepchenko 4-6 6-4 7-5 99.0 Quebec City Vickery/Tig 7-6(5) 6-7(3) 7-6(7) 98.5 Miami Garcia/Petkovic 7-6(5) 3-6 7-6(2) 98.1 Wimbledon Vesnina/Makarova 5-7 6-1 9-7 97.2 Beijing Keys/Kvitova 6-3 6-7(2) 7-6(5) 96.8 Acapulco Stephens/Cibulkova 6-4 4-6 7-6(5) 96.7
Getting to 6-6 in the final set is clearly a good way to appear on this list. The top fifty matches of the season (out of about 2,700) all reached at least 5-5 in the third. The highest-rated clash that didn’t get that far was Angelique Kerber‘s 1-6 7-6(2) 6-4 defeat of Elina Svitolina, with an EI of 88.2. Svitolina’s 4-6 6-3 6-4 victory over Bethanie Mattek Sands in Wuhan, the top match on the list without any sets reaching 5-5, scored an EI of 87.3.
Wimbledon featured an unusual number of very exciting matches this year, especially compared to Roland Garros and the Australian Open, the other tournaments that forgo a tiebreak in the final set. The top-rated French Open contest was the first-rounder between Johanna Larsson and Magda Linette, which scored 95.3 and ranks 13th for the season, while the highest EI among Aussie Open matches is all the way down at 27th on the list, a 92.8 between Monica Puig and Kristyna Pliskova.
Dominika Cibulkova is the only player who appears twice on this list. That doesn’t mean she’s a sure thing for exciting matches: As we’ll see, elite players rarely are. The only year-end top-tenner who ranks among the highest average EIs is Svetlana Kuznetsova, who played as many “very exciting” matches–those rating among the top fifth of matches this season–as any other woman on tour:
Rank Player M Avg EI V. Exc Exc % Bor % 1 Kristina Mladenovic 60 59.8 19 55.0% 25.0% 2 Christina McHale 46 59.6 16 50.0% 19.6% 3 Heather Watson 35 58.5 12 48.6% 25.7% 4 Jelena Jankovic 43 57.6 12 55.8% 30.2% 5 Svetlana Kuznetsova 64 57.4 21 48.4% 32.8% 6 Venus Williams 38 57.1 10 55.3% 31.6% 7 Yanina Wickmayer 43 56.5 13 46.5% 30.2% 8 Alison Riske 46 56.5 10 45.7% 32.6% 9 Caroline Garcia 62 56.4 18 43.5% 33.9% 10 Irina-Camelia Begu 42 56.4 14 45.2% 40.5%
(Minimum 35 tour-level matches (“M” above), excluding retirements. My data is also missing a random handful of matches throughout the season.)
The “V. Exc” column tallies how many top-quintile matches the player took part in. The “Exc %” column shows the percent of matches that rated in the top 40% of all WTA contests, while “Bor %” shows the same for the bottom 40%, the more boring matches. Big servers who reach a disproportionate number of tiebreaks and 7-5 sets do well on this list, though it is far from a perfect correspondence. Tiebreaks can create a lot of big moments, but if there were many love service games en route to 6-6, the overall picture isn’t nearly so exciting.
Unlike Kuznetsova, who played a whopping 32 deciding sets this year, most of the other top women enjoy plenty of blowouts. Muguruza, Simona Halep, and Serena Williams occupy the very last three places on the average-EI ranking, largely because when they win, they do so handily–and they win a lot. The next table shows the WTA year-end top-ten, with their ranking (out of 59) on the average-EI list:
Rank Player WTA# Matches Avg EI V. Exc Exc % Bor % 5 Kuznetsova 9 64 57.4 21 48.4% 32.8% 13 Pliskova 6 66 55.6 19 48.5% 39.4% 16 Keys 8 64 55.4 13 40.6% 35.9% 23 Cibulkova 5 68 54.6 21 42.6% 42.6% 28 Kerber 1 77 54.0 12 42.9% 41.6% tour average 53.7 40.0% 40.0% 41 Radwanska 3 69 52.5 12 29.0% 44.9% 51 Konta 10 67 51.2 12 34.3% 46.3% 57 Muguruza 7 51 49.9 5 33.3% 43.1% 58 Halep 4 59 49.6 8 30.5% 50.8% 59 Williams 2 44 48.1 3 27.3% 50.0%
It’s a good thing that fans love Serena, because her matches rarely provide much in the way of big moments. As low as Williams and Halep rate on this measure, Victoria Azarenka scores even lower. Her Miami fourth-rounder against Muguruza was her only match this season to rank in the “exciting” category, and her average EI was a mere 44.0.
Clearly, EI isn’t much of a method for identifying the best players. Even looking at the lowest-rated competitors by EI would be misleading: In 56th place, right above Muguruza, is the otherwise unheralded Nao Hibino. EI excels as a metric for ferreting out the most riveting individual matches, whether they were broadcast worldwide or ignored entirely. And the next time someone suggests shortening matches, EI is a great tool to highlight just how much excitement would be lost by doing so.