What Cincinnati Taught Us About the Serve Clock

Italian translation at settesei.it

So far, the serve clock has not made matches faster. In my article for The Economist earlier this week, I showed that in the handful of tournaments played with the new technology thus far, players took longer to play each point than they did at the same events last year.

That article included data from San Jose, Washington, Toronto, and Montreal. Last week, the combined Masters/Premier event in Cincinnati gave us another several dozen matches, with a slightly different mix of players, to further test how the serve clock is affecting the speed of play. Given another week of experience with the visible timers, the pace of play remains slower than it was one year ago.

In the Cincinnati men’s event, players used 41.2 seconds per point this year, compared to 39.8 seconds per point last year. In the women’s draw, it was 40.8 seconds per point this year, up from 40.2 seconds per point last year. Both increases are roughly the average change that we saw in the tournaments of the two previous weeks. Here is a breakdown of the time per point at each event, where “S/P” means seconds per point. Also shown are tour and overall averages, weighted by the number of matches at each event:

M/W      Tournament  2017 S/P  2018 S/P  Change  
Men      Cincinnati      39.8      41.2    +1.4  
Men      Canada          40.2      41.4    +1.2  
Men      Washington      40.3      42.2    +1.9 
 
Women    Cincinnati      40.2      40.8    +0.6  
Women    Canada          40.7      41.8    +1.1  
Women    Washington      40.2      41.6    +1.4  
Women    San Jose        40.3      40.7    +0.4  
                                                 
Men      Average         40.1      41.6    +1.5  
Women    Average         40.4      41.2    +0.8  
Overall  Average         40.2      41.4    +1.2

* alert readers might notice small discrepancies between these figures and those cited in the Economist, which are due to rounding errors.

Several readers have commented on the imprecision of this measurement. (I did too, in the original post.) Short of taking a stopwatch to every single match, there’s no way of auditing umpires by collecting the exact length of time between each pair of points. The exact mix of players in any given draw can affect the overall measurements–I experimented with a simple model to control for players, but it presented more problems than it solved. I agree, this is far from the final word on the serve clock, even apart from the fact that the way that umpires use it will probably evolve.

Still, these numbers point in only one direction. A similar survey of unaffected tournaments confirms that 2018 is not slower in general: For instance, of the men’s and women’s draws in Indian Wells, Miami, and Madrid this year, four of the six brackets decreased in average time per point, and one of the others increased by only 0.1 seconds per point.

Also, it’s important to remember that one presumed goal of the clock is to speed up play, not simply keep it steady. If time per point were staying roughly the same as last year, that itself would indicate that the new technology isn’t living up to its billing. That seven out of seven events have all gotten slower allows us to make an even stronger claim.

Fortunately for the tours, there is plenty of room for the use of the clock to evolve. The most glaring example is the umpiring practice of waiting until crowd noise dies down to start the clock. Yes, players can’t be expected to serve in a noisy stadium, but the cheering usually stops after ten seconds or so. Rather than add that ten seconds to the time allotment between points, umpires should start the clock immediately and then, on the rare occasions when the crowd remains disruptive, pause as necessary.

Its unlikely that matches will still be slower when the serve-clock dust has settled. But the goalposts have moved: At this stage of the process, it would be progress if matches with visible timers were simply the same speed as the ones that came before.

Economist: The new serve clock in tennis appears to be backfiring

At the Economist Game Theory blog, I wrote about the early effects of the new serve clock. The outwardly stricter time policy didn’t speed up Rafael Nadal, nor did it cut down match times in general over its first two weeks:

The Toronto champion wasn’t the only player who slowed down once on the clock. At each of the completed tournaments where the serve clock has been used—Toronto, Montreal, San Jose, and Washington, D.C.—the average point took longer in 2018 than it did in 2017, without the clock. The differences varied from 0.3 seconds per point at the women’s event San Jose (an event that was held in nearby Stanford last year) to 2.0 seconds at the men’s competition in Washington.

Read the whole thing.

Unseeded Serena and the Roland Garros Draw

In a wide-open women’s field at this year’s French Open, it seems fitting that one of the most dangerous players in the draw isn’t even seeded. Serena Williams has played only four matches–none of them on clay–since returning to tour after giving birth. As such, her official WTA ranking is No. 453, and her current match-play level is anyone’s guess.

Because her ranking is low, she needed to use the ‘special ranking’ rule to enter the tournament, and the rule doesn’t apply to seedings. (I’m not going to dive further into the debate about how the rule should work–I’ve written a lot about the rule in the past.) As an unseeded player, she could have drawn anyone in the first round; in that sense, she was a bit lucky to end up opposite another unseeded player, Kristyna Pliskova, in the first round. Her wider draw section is manageable as well, with a likely second-round match against 17th seed Ashleigh Barty and a possible third-rounder with 11th seed Julia Goerges. If she makes it to the round of 16, we’ll probably be treated to a big-hitting contest between Serena and Karolina Pliskova or Maria Sharapova.

According to my Elo-based forecast, a best guess about the level of post-pregnancy Serena is that she’s the 7th best overall player in the field, and 9th best on clay. That gives her about a 40% chance of winning her first three matches and reaching the second week, a 6.2% chance of making it to the final, and a 3.1% chance of adding yet another major title to her haul.

What if she were seeded? Seeds are a clear advantage for players who receive them, as a seeding protects against facing other top contenders until later rounds. By simulating the tournament with Serena seeded, we can get a sense of how much the WTA’s rule (and the French Federation’s decision not to seed her) impacts her chances.

Seeded 7th: Let’s imagine a bizarre world in which my Elo ratings were used for tournament seedings. In that case, Serena would be seeded 7th, knocking Caroline Garcia down to 8th and sending current 32nd seed Alize Cornet into the unseeded pool. That would be a clear advantage: 50/50 odds of reaching the fourth round, a 9% chance of playing in the final, and a 4.4% shot at the title, compared to 3.1% in reality.

Seeded 1st: If seeds were assigned based on protected ranking, Serena would be the top seed. You can’t get much more of an advantage than that: The top seed is protected from playing either of the other top-four seeds until the semifinals, for instance. (It’s no insurance against a meeting with 28th seed Sharapova, but Serena, of all people, isn’t worried about that.) Moving from 7th to 1st would give her another boost, but it’s a modest one: As the top seed, her chances of sticking around for the second week would still be 50/50, with 10.1% and 4.7% odds of reaching the final and winning the title, respectively.

Here’s a summary of Serena’s chances in the various seeding scenarios. The final column is “expected points”–a weighted average of the number of WTA ranking points she is expected to collect, given her likelihood of reaching each round.

Scenario     R16  Final  Title  ExpPts  
Actual     39.8%   6.2%   3.1%     273  
Unseeded*  34.4%   6.2%   3.0%     259  
Seeded 7   50.3%   9.0%   4.4%     356  
Seeded 1   50.5%  10.1%   4.7%     371

* the ‘unseeded’ scenario represents Serena’s chances as an unseeded entrant, given a random draw. She got a little lucky, avoiding top players until the 4th round, though her chances of making the final end up the same.

Seeds matter, though there’s only so much they can do. If Serena really is at a barely-top-ten level, she’s a long shot for the title regardless of whether there’s a number next to her name. If my model grossly underestimates her and she’s back at previous form–let’s not forget, she made the final the last time she played here, and won the title the year before that–then the rest of the field will once again look like a bunch of flies for her to swat away, regardless of which numbers they have next to their names.

Should Serena Be Seeded?

Italian translation at settesei.it

Serena Williams returned to professional tennis this month after more than a year of pregnancy, childbirth, and recovery. She took wild cards into both Indian Wells and Miami, competing as an unseeded player for the first time since August 2011. In her initial effort in California, she reached the third round before falling to sister Venus, and this week in Miami, she drew Indian Wells champ Naomi Osaka in her opening match and went home early, losing 6-3 6-2.

Seeing Serena without a number next to her name feels wrong. She left the tour for maternity leave just after winning last year’s Australian Open, a title that moved her back into the No. 1 ranking position. While she is clearly rusty–as she has been after previous absences–there’s little doubt she’ll quickly resume competing at a top-32 level (the threshold for an Indian Wells or Miami seed), if not considerably higher.

The brutal Miami draw and Serena’s ensuing early exit prompted all sorts of commentary, much of it calling for a rule change, some castigating the WTA for its lack of a maternity leave policy. The latter is not quite true: The WTA rulebook addresses absences for childbirth and treats returning players almost exactly as it handles women coming back from injury. Nevertheless, edge cases–like the greatest player in women’s tennis rejoining the tour without a single ranking point to her name–tend to put rules to the test.

Seedings are not just a convenient way to identify the top players on a printed bracket. They have an effect on the outcome of the tournament. In the March tournaments, seeded players get free passes to the second round. At every event, the seeding system keeps top players away from each other until the final rounds. Even minor differences, like the one between the fourth and fifth seeds, can have a major effect on two players’ potential routes to the title. This is all to say: Seedings matter, not just to returning players like Serena, but also to everyone else in the draw. While granting a seed to Williams right now may be the right thing to do, it would also push another seeded player into the unseeded pool, affecting that competitor’s chances at late-round ranking points and prize money. It’s important to acknowledge how the rules affect the entire field.

In a moment, I’ll outline various approaches the WTA could take to deal with future maternity leaves. I don’t have a strong opinion; there’s merit in each of them, as I’ll try to explain. What is most important to me, as a fan, is that any rules adopted are designed for the benefit of the whole tour, not just patches to handle once-in-a-generation superstars. Serena deserves a fair shake from the WTA, and her peers are entitled to the same.

1. Minor tweaks to the existing rule. The most likely outcome is almost always the status quo, and Osaka notwithstanding, the status quo is not that bad. The WTA rules allow for returning players (whether from injury or motherhood) to use a “Special Ranking” (SR) in eight events, including two slams.  The SR is the player’s ranking at the time she left the tour, and it determines whether she qualifies to enter tournaments upon her return. While Serena used wild cards for her two events thus far (more on that later), she could have used her SR for either or both.

In other words, new mothers are already allowed to pick up where they left off … with the important exception of seeding. Serena’s SR will allow her to enter, say, the French Open as if she were the No. 1 ranked player, but unless Roland Garros invokes their right to tweak seedings (like Wimbledon does), her seed will be determined by her actual ranking at that time. Since it’s only two months away, it’s very possible she’ll be unseeded there as well, making possible another nasty first-round matchup in the vein of the Simona HalepMaria Sharapova opener at last year’s US Open.

The debate over seeding boils down to “respect” versus “practicality.” Serena’s achievements and her probable quick return to greatness suggest that she “deserves” to be seeded as such. On the other hand, many players (including Sharapova, different as her situation is) have had a hard time returning to their previous level. The post-comeback results of Sharapova or, more recently, Novak Djokovic, indicates that a star’s ranking 12 months ago might not tell you much about how she’ll play now. Seedings exist partly to induce top players to compete, but also to increase the likelihood that the best women will face each other in the final rounds. By the latter criterion, it’s not clear that Serena (or any returning player) should immediately reclaim a top seed.

If the WTA does stick with this basic principle, I would suggest offering a few more SR entries–perhaps 12 instead of 8, and 3 slams instead of 2. Maternity leave necessitates more time on the sidelines than the six-month injury break required to qualify for the SR rule, and it may require still more time to return to form. The WTA might also convince the ITF to offer an additional few SR entries to lower-level events. Kei Nishikori came back from injury by playing a couple of Challengers; women might prefer to get their feet wet with a few ITF $100Ks before using their SR entries on top-tier events.

2. Link seeding to Special Rankings. The second option is essentially what fans wanted when they realized Serena might not make it to the Miami second round. Instead of using current ranking to determine seeding, tournaments could use SR for players who used them to enter the event.

There is a precedent for this: Monica Seles was given a top seeding when she returned from injuries sustained during her 1993 on-court stabbing. More than two years later, she came back as the top seed in Canada and the second seed at the 1995 US Open, where she lived up to that draw placement, winning 11 matches in a row before falling to Steffi Graf in the New York final.

The pros and cons of this route are the opposite of the first proposal. Giving players their pre-break seeding would show respect for their accomplishments, but since most players don’t come back from any length time off court the way Seles did, it’s possible the seedings would appear overly optimistic. (And yes, I realize the irony of saying so during the 2018 Miami tournament, when the top two seeded women won only one match between them.)

3. Devise a time-off-court algorithm. Players usually need some time to resume their former level, but their skill upon return has some relationship to how they played before. When I wrote about Sharapova’s return from her drugs ban last year, I showed that elite players who missed a year or more (for whatever reason), tended to play much worse than their pre-break level for their first five or so matches, and then a moderately lower level for the next 50. I measured it in Elo points: a 200 point drop at first, then a 100 point drop.

I don’t expect the WTA to adopt Elo anytime soon, but an algorithm of this sort could be based on any ranking system, and it represents a reasonable compromise between the first two positions. For someone as dominant as Serena, it would fulfill most of her fans’ wishes: A 200-point drop from her pre-break level would still leave her roughly even with Halep, meaning that a system of this sort would’ve made her the first or second seed in this month’s draws.

A better illustration of how the algorithm would work requires a player who didn’t so overwhelmingly outclass the rest of the field: If Wozniacki (current Elo: 2156) were to miss the next year, her seeding upon return would use an Elo 200 points lower, of 1956, dropping her to about 30th (assuming all the top players were competing). After the first five matches, when players usually start getting their groove back, her seedings would rise to around 15th. Several months in, her ranking would rise, and her seeding would no longer need to be adjusted.

The obvious flaw here is the level of complexity. My algorithm is approximate at best and would need to be improved for such an important role. The advantage, though, is that if an acceptable formula could be found, it would allow the WTA to offer a perfect compromise between the needs of returning mothers and the rights of the rest of the field.

And about those wild cards… 

I’ve mentioned that Serena used wild cards to enter both Indian Wells and Miami, even though she could have used her Special Ranking. Just about every WTA event would happily hand her a wild card, as they should. So in Serena’s case, the SR rule is largely irrelevant–if it didn’t exist, she could immediately resume a full schedule.

I also wrote that, as a fan, what matters to me is that all tour players are treated equally. Tournament entries are opportunities to gain ranking points, which in turn determine entries and seeding, which affects the likelihood of racking up wins and titles. Wild cards are often thought of as gifts, but we rarely acknowledge the effect that those gifts have on the players who rarely get them. Because tournaments understandably tend to hand out free passes to home-country players (like Donald Young) and marquee personalities (like Eugenie Bouchard), the wild card system introduces systemic bias into rankings and results. Wild cards can’t make a journeyman into a superstar, but they can boost a player from the top 200 to the top 100, or from No. 70 to No. 50. For some tour players, these differences really matter.

Thus, when a superstar or media darling–or just a player from a country that happens to host a lot of tournaments, like the United States–returns from maternity leave, injury, or a suspension, the regular rules don’t apply. Maria Sharapova was wild carded into most of the tournaments she wanted to play last year, while Sara Errani has spent the last six months playing ITFs, $125Ks, and qualifying. Sharapova gets to play matches with 100 ranking points at stake while Errani contests entire tournaments with less on the line.

Wildly different as their cases are, Serena’s situation with regard to wild cards is the same as Sharapova’s. Her allotment of SR entries doesn’t matter. But imagine if, say, Anastasija Sevastova or Magdalena Rybarikova took time off to have a child. They might get a few free entries into European international-level events, or maybe a wild card into a tournament they’ve previously won. But for the most part, a Sevastova or a Rybarikova–despite taking her hypothetical absence while a top-20 player–would be jealously protecting her eight SRs. She would need them.

Just to be clear, I’m not trying to say that Serena doesn’t “deserve” all the wild cards she’s going to get. Her achievements make it obvious that she does. On a tour where events can award draw places at their discretion, no one deserves them more. However, the very existence of those discretionary spots means that maternity leave means something very different for Serena than it would for the more anonymous players near the top of the WTA rankings.

How about this proposal, then: For players coming back from maternity leave, expand the number of SR entries from 8 to 12, and tack on another four free entries to ITFs, so that returning players can have a child knowing that they’ll be able to compete at the top level for nearly a season once they come back. But–they may accept no wild cards during that time. If they take a wild card, they lose their SRs. That proposal would put all players on an even keel: Close to a year of tournament entries at their pre-break ranking. It would give the next Serena-level superstar plenty of time to regain her lost status, and best of all, it would do the same for her lesser-known peers.

Measuring the Impact of Wimbledon’s Seeding Formula

Italian translation at settesei.it

Unlike every other tournament on the tennis calendar, Wimbledon uses its own formula to determine seedings. The grass court Grand Slam grants seeds to the top 32 players in each tour’s rankings, and then re-orders them based on its own algorithm, which rewards players for their performance on grass over the last two seasons.

This year, the Wimbledon seeding formula has more impact on the men’s draw than usual. Seven-time champion Roger Federer is one of the best grass court players of all time, and though he dominated hard courts in the first half of 2017, he still sits outside the top four in the ATP rankings after missing the second half of 2016. Thanks to Wimbledon’s re-ordering of the seeds, Federer will switch places with ATP No. 3 Stan Wawrinka and take his place in the draw as the third seed.

Even with Wawrinka’s futility on grass and the shakiness of Andy Murray and Novak Djokovic, getting inside the top four has its benefits. If everyone lives up to their seed in the first four rounds (they won’t, but bear with me), the No. 5 seed will face a path to the title that requires beating three top-four players. Whichever top-four guy has No. 5 in his quarter would confront the same challenge, but the other three would have an easier time of it. Before players are placed in the draw, top-four seeds have a 75% chance of that easier path.

Let’s attach some numbers to these speculations. I’m interested in the draw implications of three different seeding methods: ATP rankings (as every other tournament uses), the Wimbledon method, and weighted grass-court Elo. As I described last week, weighted surface-specific Elo–averaging surface-specific Elo with overall Elo–is more predictive than ATP rankings, pure surface Elo, or overall Elo. What’s more, weighted grass-court Elo–let’s call it gElo–is about as predictive as its peers for hard and clay courts, even though we have less grass-court data to go on. In a tennis world populated only by analysts, seedings would be determined by something a lot more like gElo and a lot less like the ATP computer.

Since gElo ratings provide the best forecasts, we’ll use them to determine the effects of the different seeding formulas. Here is the current gElo top sixteen, through Halle and Queen’s Club:

1   Novak Djokovic         2296.5  
2   Andy Murray            2247.6  
3   Roger Federer          2246.8  
4   Rafael Nadal           2101.4  
5   Juan Martin Del Potro  2037.5  
6   Kei Nishikori          2035.9  
7   Milos Raonic           2029.4  
8   Jo Wilfried Tsonga     2020.2  
9   Alexander Zverev       2010.2  
10  Marin Cilic            1997.7  
11  Nick Kyrgios           1967.7  
12  Tomas Berdych          1967.0  
13  Gilles Muller          1958.2  
14  Richard Gasquet        1953.4  
15  Stanislas Wawrinka     1952.8  
16  Feliciano Lopez        1945.3

We might quibble with some these positions–the algorithm knows nothing about whatever is plaguing Djokovic, for one thing–but in general, gElo does a better job of reflecting surface-specific ability level than other systems.

The forecasts

Next, we build a hypothetical 128-player draw and run a whole bunch of simulations. I’ve used the top 128 in the ATP rankings, except for known withdrawals such as David Goffin and Pablo Carreno Busta, which doesn’t differ much from the list of guys who will ultimately make up the field. Then, for each seeding method, we randomly generate a hundred thousand draws, simulate those brackets, and tally up the winners.

Here are the ATP top ten, along with their chances of winning Wimbledon using the three different seeding methods:

Player              ATP     W%  Wimb     W%  gElo     W%  
Andy Murray           1  23.6%     1  24.3%     2  24.1%  
Rafael Nadal          2   6.1%     4   5.7%     4   5.5%  
Stanislas Wawrinka    3   0.8%     5   0.5%    15   0.4%  
Novak Djokovic        4  34.1%     2  35.4%     1  34.8%  
Roger Federer         5  21.1%     3  22.4%     3  22.4%  
Marin Cilic           6   1.3%     7   1.0%    10   1.0%  
Milos Raonic          7   2.0%     6   1.6%     7   1.7%  
Dominic Thiem         8   0.4%     8   0.3%    17   0.2%  
Kei Nishikori         9   1.9%     9   1.7%     6   1.9%  
Jo Wilfried Tsonga   10   1.6%    12   1.4%     8   1.5%

Again, gElo is probably too optimistic on Djokovic–at least the betting market thinks so–but the point here is the differences between systems. Federer gets a slight bump for entering the top four, and Wawrinka–who gElo really doesn’t like–loses a big chunk of his modest title hopes by falling out of the top four.

The seeding effect is a lot more dramatic if we look at semifinal odds instead of championship odds:

Player              ATP    SF%  Wimb    SF%  gElo    SF%  
Andy Murray           1  58.6%     1  64.1%     2  63.0%  
Rafael Nadal          2  34.4%     4  39.2%     4  38.1%  
Stanislas Wawrinka    3  13.2%     5   7.7%    15   6.1%  
Novak Djokovic        4  66.1%     2  71.1%     1  70.0%  
Roger Federer         5  49.6%     3  64.0%     3  63.2%  
Marin Cilic           6  13.6%     7  11.1%    10  10.3%  
Milos Raonic          7  17.3%     6  14.0%     7  15.2%  
Dominic Thiem         8   7.1%     8   5.4%    17   3.8%  
Kei Nishikori         9  15.5%     9  14.5%     6  15.7%  
Jo Wilfried Tsonga   10  14.0%    12  13.1%     8  14.0%

There’s a lot more movement here for the top players among the different seeding methods. Not only do Federer’s semifinal chances leap from 50% to 64% when he moves inside the top four, even Djokovic and Murray see a benefit because Federer is no longer a possible quarterfinal opponent. Once again, we see the biggest negative effect to Wawrinka: A top-four seed would’ve protected a player who just isn’t likely to get that far on grass.

Surprisingly, the traditional big four are almost the only players out of all 32 seeds to benefit from the Wimbledon algorithm. By removing the chance that Federer would be in, say, Murray’s quarter, the Wimbledon seedings make it a lot less likely that there will be a surprise semifinalist. Tomas Berdych’s semifinal chances improve modestly, from 8.0% to 8.4%, with his Wimbledon seed of No. 11 instead of his ATP ranking of No. 13, but the other 27 seeds have lower chances of reaching the semis than they would have if Wimbledon stopped meddling and used the official rankings.

That’s the unexpected side effect of getting rankings and seedings right: It reduces the chances of deep runs from unexpected sources. It’s similar to the impact of Grand Slams using 32 seeds instead of 16: By protecting the best (and next best, in the case of seeds 17 through 32) from each other, tournaments require that unseeded players work that much harder. Wimbledon’s algorithm took away some serious upset potential when it removed Wawrinka from the top four, but it made it more likely that we’ll see some blockbuster semifinals between the world’s best grass court players.

Regulations for Returning Rule-Breakers

Italian translation at settesei.it

Next month, Maria Sharapova will complete her 15-month doping ban and return to the WTA tour in Stuttgart, where she has been granted a wild card. It’s no surprise that tournaments are eager to invite an extremely marketable former No. 1, and Sharapova has already lined up wild cards for the Premier-level events in Madrid and Rome.

This has generated no small amount of controversy. Many people see wild cards as a sort of reward or gift that is inappropriate for a player caught breaking such a serious rule. Many fans and fellow players think that, even after she has undergone a severe penalty, Sharapova doesn’t deserve this type of advantage.

Crucially, neither the ITF–which handles drug testing and issued the suspension–nor the WTA–which sets the guidelines for tournament entry–has anything to say about the situation. Each event must make its own decision. The French Open may refuse to invite Sharapova this year (and Wimbledon could follow suit) but any other tournament organizer who cares about selling tickets and sponsorships would want her in the draw.

In other words, with the possible exception of Paris and London, Sharapova will be able to pick up where she left off, entering whichever tournaments she wishes. The only disadvantage is that she won’t be seeded, meaning that we could see some draws that will make the Indian Wells quarter of death look like a friendly club tournament. If she plays well and stays healthy, she’ll probably earn her way to some seeds before the end of the season.

I’m not interested the argument about whether Sharapova “deserves” these wild cards. I’m not a fan of tournaments handing prize money and ranking points opportunities to favorites in any case, but on the other hand, Maria’s penalty was already severe. It doesn’t seem right that she would spend months scrambling for points in lower-level ITFs. When Viktor Troicki was suspended for one year in 2013, he was granted only two tour-level wild cards, so he needed six months to regain his former ranking.

My concern is for the Troickis of the tennis world. Both Sharapova’s and Troicki’s comebacks will ultimately be shaped by the decisions of individual tournaments, so Sharapova–an immensely marketable multiple-Slam winner–will get in almost everywhere she wants, while Troicki was forced to start almost from zero. Put another way: Sharapova’s 15-month ban will last 15 months (exactly 15 months, since she’ll play her first-round match in Stuttgart on the first possible day) while Troicki’s 12-month suspension knocked him out of contention for almost 18 months.

The WTA needs a set of rules that determine exactly what a player can expect upon return from a suspension. Fortunately, they already have something in place that can be adapted to serve the purpose: the “special ranking” for those with long-term injuries. (The ATP’s “protected ranking” rule is similar.) If a player is out of action for more than six months, she can use the ranking she held when she last competed to enter up to eight events, including up to two Premier Mandatories and two Grand Slams. Whether the player is iconic or anonymous, she has a fair chance to rebuild her ranking after recovering from injury.

This is my proposal: When a player returns from suspension, treat her like a player returning from injury, with one difference: For the first year back, no wild cards.  Sharapova would get into eight events–she might choose Stuttgart, Rome, Madrid, Roland Garros, Birmingham, Wimbledon, Toronto, and Cincinnati. If she played well in her first two months back, she would probably have a high enough ranking to get into the US Open without help, and the whole issue would cease to matter.

The details don’t need to be exactly the same as post-injury comebacks. I can imagine including two to four additional special ranking entries into ITFs or qualifying, in case a player wants to work her way back to tour level, as a sort of rehab assignment. The important thing here is that the rules would be the same for everyone. As harsh as Sharapova’s penalty is, it pales in comparison to the effect a 15-month ban could have on a less popular tour regular, as Troicki’s example demonstrates.

Like it or not, there will be more doping bans, and unless the tours institute this sort of standardized treatment, there will be more controversies about whether this player or that player deserves wild cards after they return to the tour. The ultimate severity of a penalty will always depend on many factors, but a player’s popularity should never be one of them.

Forecasting the Effects of Performance Byes in Beijing

To the uninitiated, the WTA draw in Beijing this week looks a little strange. The 64-player draw includes four byes, which were given to the four semifinalists from last week’s event in Wuhan. So instead of empty places in the bracket next to the top four seeds, those free passes go to the 5th, 10th, and 15th seeds, along with one unseeded player, Venus Williams.

“Performance byes”–those given to players based on their results the previous week, rather than their seed–have occasionally featured in WTA draws over the last few years. If you’re interested in their recent history, Victoria Chiesa wrote an excellent overview.

I’m interested in measuring the benefit these byes confer on the recipients–and the negative effect they have on the players who would have received those byes had they been awarded in the usual way. I’ve written about the effects of byes before, but I haven’t contrasted different approaches to awarding them.

This week, the beneficiaries are Garbine Muguruza, Angelique Kerber, Roberta Vinci, and Venus Williams. The top four seeds–the women who were atypically required to play first-round matches, were Simona Halep, Petra Kvitova, Flavia Pennetta, and Agnieszka Radwanska.

To quantify the impact of the various possible formats of a 64-player draw, I used a variety of tools: Elo to rate players and predict match outcomes, Monte Carlo tournament simulations to consider many different permutations of each draw, and a modified version of my code to “reseed” brackets. While this is complicated stuff under the hood, the results aren’t that opaque.

Here are three different types of 64-player draws that Beijing might have employed:

  1. Performance byes to last week’s semifinalists. This gives a substantial boost to the players receiving byes, and compared to any other format, has a negative effect on top players. Not only are the top four seeds required to play a first-round match, they are a bit more likely to play last week’s semifinalists, since the byes give those players a better chance of advancing.
  2. Byes to the top four seeds. The top four seeds get an obvious boost, and everyone else suffers a bit, as they are that much more likely to face the top four.
  3. No byes: 64 players in the draw instead of 60. The clear winners in this scenario are the players who wouldn’t otherwise make it into the main draw. Unseeded players (excluding Venus) also benefit slightly, as the lack of byes mean that top players are less likely to advance.

Let’s crunch the numbers. For each of the three scenarios, I ran simulations based on the field without knowing how the draw turned out. That is, Kvitova is always seeded second, but she doesn’t always play Sara Errani in the first round. This approach eliminates any biases in the actual draw. To simulate the 64-player field, I added the four top-ranked players who lost in the final round of qualifying.

To compare the effects of each draw type on every player, I calculated “expected points” based on their probability of reaching each round. For instance, if Halep entered the tournament with a 20% chance of winning the event with its 1,000 ranking points, she’d have 200 “expected points,” plus her expected points for the higher probabilities (and lower number of points) of reaching every round in between. It’s simply a way of combining a lot of probabilities into a single easier-to-understand number.

Here are the expected points in each draw scenario (plus the actual Beijing draw) for the top four players, the four players who received performance byes, plus a couple of others (Belinda Bencic and Caroline Wozniacki) who rated particularly highly:

Player               Seed  PerfByes  TopByes  NoByes  Actual  
Simona Halep            1       323      364     330     341  
Petra Kvitova           2       276      323     290     291  
Venus Williams                  247      216     218     279  
Belinda Bencic         11       255      249     268     254  
Garbine Muguruza        5       243      202     210     227  
Angelique Kerber       10       260      224     235     227  
Caroline Wozniacki      8       208      203     205     199  
Flavia Pennetta         3       142      177     144     195  
Agnieszka Radwanska     4       185      233     192     188  
Roberta Vinci          15       120       91      94      90

As expected, the top four seeds are expected to reap far more points when given first-round byes. It’s most noticeable for Pennetta and Radwanska, who would enjoy a 20% boost in expected points if given a first-round bye. Oddly, though, the draw worked out very favorably for Flavia–Elo gave her a 95% chance of beating her first-round opponent Xinyun Han, and her draw steered her relatively clear of other dangerous players in subsequent rounds.

Similarly, the performance byes are worth a 15 to 30% advantage in expected points to the players who receive them. Vinci is the biggest winner here, as we would generally expect from the player most likely to suffer an upset without the bye.

Like Pennetta, Venus was treated very well by the way the draw turned out. The bye already gave her an approximately 15% boost compared to her expectations without a bye, and the draw tacked another 13% onto that. Both the structure of the draw and some luck on draw day made her the event’s third most likely champion, while the other scenarios would have left her in fifth.

All byes–conventional or unconventional–work to the advantage of some players and against others. However they are granted, they tend to work in favor of those who are already successful, whether that success is over the course of a year or a single week.

Performance byes are easy enough to defend: They give successful players a bit more rest between two demanding events, and from the tour’s perspective, they make it a little more likely that last week’s best players won’t pull off of this week’s tourney. And if all byes tend to the make the rich a little richer, at least performance byes open the possibility of benefiting different players than usual.

Saving Time With One-Ad and Short-Set Formats

Earlier this week, a USTA advisory group proposed some major changes to the collegiate “dual match” format so that it would better fit three-hour television windows.  Most of those involved in college tennis hated the proposal, especially since it virtually eliminates doubles.

Now, the Intercollegiate Tennis Association has issued a counterproposal, a sort of compromise that attempts to shorten the time required by dual matches while retaining the importance of the doubles point. (As usual, Colette Lewis has the scoop. Click that link for her take.)

The ITA’s suggestions boil down to this:

  • Each game follows the “one-ad” format–after deuce is reached the second time, a single point is played to decide the game.
  • Both singles and doubles sets will be played to 5, with a tiebreak played at 5-all.  Currently, doubles sets are played to 7, while singles are played to the conventional 6.

Does this proposal have a chance of solving the problem it aims to address?  How much time will these changes save?

One-ad scoring

On Tuesday, I shared my findings that “no-ad” scoring–that is, the format used by WTA and ATP doubles, and one often proposed by those hoping to shorten any level of tennis–can be expected to reduce the length of the average match by about 10%.

(Today, I’m sticking with percentages, since college matches may last considerably longer than pro matches.  In an ATP Challenger match, that typical 10% reduction amounts to eight minutes; in college, it might be as much as twice as long.)

Of course, “one-ad” scoring will not have as much of an impact.  In ATP Challenger matches this year, 11% of games have gone to a second deuce.  Those second-deuce games, which short-ad would reduce to nine points, averaged 11.8 points.  Thus, going to ‘short-ad’ would reduce the number of points per game by six or seven points per match.  The effect is roughly half that of no-ad.  On a percentage basis, it might be expected to cut match length by 5%.

Recognizing the limitations of ATP Challenger data, I also researched the same numbers using 2013 women’s ITF tournaments, running the gamut from 10K to 100K tournaments.  The numbers are roughly the same; two-deuce games go to 11.9 points, and the overall effect would be a little more than seven points per match.  In the aggregate, we might be looking at  a time reduction of 6% instead of 5%.

While one-ad is a creative compromise between purists and reformers, it probably isn’t enough to get the job done.  A dual match that would otherwise last three and a half hours would be cut by ten or twelve minutes.

Short sets

At first glance, the proposal to stop sets at five instead of six (or seven, in the case of doubles) seems like a tweak more cosmetic than anything else.  Because the doubles matches are played simultaneously and the singles matches are played simultaneously, dual matches often leave several individual matches abandoned.  The matches that would go to a third-set tiebreak rarely get that far.  The relatively quick 6-4 6-2 contests are more likely to count toward the end result.

Still, let’s ignore the simultaneous format for a moment.  How many matches is this tweak likely to affect?

The only singles sets that will be consistently shorted by this proposal are those that currently reach tiebreaks.  A tiebreak is roughly equivalent to two games, so playing a tiebreak at 5-5 requires about the same amount of time as reaching 7-5.

Now using ITF women’s 10K’s as our sample, we can find that singles matches average roughly one tiebreak per six matches.  Using the shorthand of “one tiebreak equals two games,” that means that the time savings is about one game per three matches.  The average match lasts about twenty games, so that’s one game saved per sixty, or a bit less than 2%.  I suppose it might help shorten dual matches in which several simultaneous singles are all going to tiebreaks, but at the aggregate level, short singles sets are less than half as effective as one-ad scoring.

Estimating the time-saving effect of short doubles sets is more difficult, because I don’t have any raw data on first-to-7 doubles sets.

Certainly, cutting two games from the total would be expected to have more than double the effect of one.   Instead of simply avoiding 7-6 sets in singles, we’re avoiding 8-6 and 8-7 sets in doubles.  Let’s say, for the sake of argument, that the time savings in these close sets is triple that of singles matches, or 6%.

Since doubles sets are cut to first-to-six instead of first-to-seven, lopsided sets will get a little faster, too.  For instance, a 7-3 set will be cut to 6-3 or 6-2.  Without knowing the distribution of various doubles scorelines, this is all guesswork, but if the lopsided sets are reduced in time by 12-15% and closer sets are less common, we might guess that the time saved in doubles is, on average, about 10%.

However, that’s 10% of a shorter length of time.  Given that doubles points are generally shorter, and that doubles is one set as opposed to two or three sets in singles, the weighted average of time savings is probably about 4.5%.

Impact of the ITA proposal

Start with the assumption (however questionable, as I discussed Tuesday) of an average dual match length of three and a half hours.  By cutting each set to first-to-five, we can expect a reduction of 4.5%, or perhaps nine minutes.   That leaves us with 3:21.

Cut off another 5% to 6% for short-ad scoring, and we save another 10 to 12 minutes.  Best case scenario, the overall length comes down to 3:09, for a total savings of just over twenty minutes.

Is that good enough?  With on-court warmups eliminated, as both the USTA Advisory Group and the ITA have proposed, it might cut a half hour from each dual match.  Still, that leaves plenty of dual matches on the wrong side of three hours.  Fine with me, and fine with a whole lot of people in college tennis, but probably not good enough for the USTA and its broadcast partners.

Time-Saving Shenanigans and the Effect of No-Ad

Yesterday, Colette Lewis reported on another set of possible rule changes for college tennis.  The goals, as always, are to shorten matches, increase television coverage, and systematically ignore the well-informed preferences of those most closely involved with the game.

Colette does a better job of explaining the limitations of the proposed format than I would, so I encourage you to go read her post.

So that we’re all on the same page, let’s summarize the most recent dual-match format:

  • Dual matches–meetings between two schools–have six players to a side. There are three doubles and six singles matches.  The combined results of the doubles matches is worth one point, and every singles match is worth one point, for a total of seven.  The first school to four points wins.
  • First, three doubles matches are played simultaneously.  Each is a single set, first to seven, win by two, and a tiebreak is played at 8-8.  If one school wins two of the three doubles matches while the other is still in progress, the third is abandoned.
  • Next, all six singles matches are played simultaneously.  Each singles match is best of three tiebreak sets.  Once one school has accumulated four points (including the doubles point), the remaining matches are abandoned, and the contest is over.

And here’s the new version:

  • Singles first.  The singles format stays the same, with six simultaneous matches.
  • If and only if a team does not accumulate four points in the singles, a compressed version of the doubles is played: the three doubles matches are reduced to 10-point super-tiebreaks. (This time last year, we were debating the merits of those as third sets.)

The proposed alternative would certainly save time.  It would also effectively destroy doubles as an important part of college tennis.

At last year’s NCAA Men’s Team Championships, 44 of the 63 dual matches were decided by a score of 4-0 or 4-1.  While it’s impossible to know how the abandoned singles matches would have turned out, it’s safe to assume that almost all of those meetings–along with many of the 4-2 outcomes and a few of the 4-3’s–would have been decided before any doubles was necessary.

Since length is such an important part of these debates, I ran some numbers to see what else might be done.

No-ad, no-overtime

The most popular device for speeding up tennis is “no-ad” scoring.  You’re probably familiar with it, as both the ATP and WTA tours use it for doubles.  Once a game reaches 40-40, the receiving team decides whether to play a final point in the deuce or ad court, and the outcome of that point decides the game.

So, how much time does it save? To get a rough idea of the answer, I looked at roughly 3600 ATP Challenger singles matches from this year.  (It’s not the most relevant dataset, I realize, but better “available” than “ideal.”)

In those matches, 24.2% of games went to deuce.  Those games averaged 9.7 points each, meaning that a switch to the no-ad format would save 2.7 points per deuce game.  Overall, such a change would save about 0.65 points per game across the board.  The average best-of-three-sets match lasts about 22 games, so switching to no-ad scoring would reduce the number of points in the typical match by 14 or 15.

At the ATP level, each additional point within a game–that is, one that doesn’t add to the number of changeovers or set breaks–adds about 33 seconds to the length of the match.  So the switch to no-ad scoring would shorten the length of an average match by about eight minutes.

Switching doubles to no-ad would have a lesser effect, because the matches are already shorter.  Figuring an average match length of 10 to 12 games, that’s another four minutes saved.

The impact is a bit more ambiguous than I’ve made it out to be, because no-ad scoring makes service breaks more common.  If the server has a 65% chance of winning a point (typical for male tour pros), he or she has only a 65% chance of holding from deuce in the no-ad format.  The server’s chances might be a bit worse, assuming the returner chooses the side which favors him or her.  In an ad game, that same server has a 77.5% chance of holding from deuce.

It would take a much more in-depth simulation (informed by much more college-specific assumptions) to know the impact of that difference.  Some additional breaks would speed up matches, making 6-0 and 6-1 outcomes more likely, while others would push sets to tiebreaks.

But college tennis takes longer

So far, I’ve been forced to use numbers from the pros to evaluate proposals for collegiates.  Somewhere along the line, the numbers don’t add up.

According to the advisory group responsible for the “hide-doubles-in-the-attic” proposal, the average dual match time at last year’s NCAA championships was over three and a half hours.  What’s taking so long?

On the ATP tour, the average best-of-three match is just over 90 minutes.  Doubles generally moves more quickly, so the first-to-seven matches should be less than half as long.  Plus, since dual matches are often decided while the longest singles matches are still going, the average completed match must be shorter than the average match at the college level.

Thus, even accounting for less serve dominance, longer rallies, and assorted factors such as the absence of ballkids and the higher number of lets (remember, these matches are played on adjacent courts), how are we getting so far beyond the magic three-hour time frame?

One explanation is simply poor data collection and analysis.  The numbers the advisory group cites are from last year’s team championships, a particularly small sample.  And by using an average, and not a median, one or two very long matches can skew the numbers–especially with such a small sample.  The five-hour dual matches are surely beyond saving, so why give them so much weight?

An alternative explanation is that college tennis really is that much slower, in which case many of the numbers I cited above don’t tell the whole story.  Are there far more deuce games in college than the 24.2% on the Challenger tour?  Are interminable, 15- to 20-point deuce games much more common?  Do points take considerably longer?

If so, the effect of moving to no-ad scoring would be greater than the twelve-minute conclusion I reached above.  Twelve minutes is a little less than one-tenth of my estimate for equivalent ATP matches, assuming a 90-minute average singles match and 45 minutes for doubles.  So if dual matches are really lasting three hours and 40 minutes, the equivalent time reduction would be almost double–better than 20 minutes.

Purists may hate no-ad scoring, but given a choice between losing 15-point deuce games and losing college doubles, I’d ditch dramatic deuce games in a second.

How to Fix the ATP’s 25-Second Rule

At the beginning of 2013, the ATP lessened the penalties for time violations, in hopes that chair umpires would call them more often. In a perfect world, that might lead to players committing fewer time violations.

So far this year, the new policy may have sped up the game a bit, but unsurprisingly, it has led to more disruptions of play.  Whenever a violation is called, an additional delay is virtually automatic.  After all, if a player is worn out from the previous point and lagging so much that he earns a time violation, why not take the opportunity to argue with the ump and physically recover for even longer?

Any time-violation policy should take into account three key guidelines:

  1. The game should move along at a reasonable pace. Some kind of time violation rule is here to stay.
  2. Any rule should be applied as fairly and consistently as possible, against all players, regardless of court, tournament, round, or set.
  3. Enforcement should interfere as little as possible with the flow of the game, both for fan enjoyment and player concentration.

The policy may be succeeding on (1).  It might be an improvement towards (2), though based on the unscientific sample of matches I’ve watched, it still seems that violations are more likely to be called on the guys playing the big four (or top ten) than the big four themselves.

As for (3), it’s a disaster.

Keep the penalties; keep the flow.

The solution is simple.  Instead of calling the time violation while the server is readying himself for the next point, call it immediately after the point is complete.  There may still be an argument, but coming right after a point instead of 30 seconds after (and five seconds before the next one would have started), it would be less disruptive.

Sometimes a post-point violation warning wouldn’t be disruptive at all, as when the point finishes a game.  Also, if the offending player has just won a point, he would probably be more in the mood to keep going than to stop and argue with the umpire.

This change would address (3).  However, to ensure that the rule is justly applied, a better system needs to be in place.  While a basketball-style shot clock is appealing for this reason, it would be far too distracting to both players and fans.  As always, the onus is on the chair umpire.

To keep the umpire honest, his record of the match should be made available to both players and their camps.  (Or best of all, to the public, but why suggest something the ATP would never consider?)

The umpire already keeps a point-by-point record of the match–that’s what you see him doing when he taps on the screen in front of him.  We’re talking about a minor technological improvement here: When he finishes entering the previous point, a clock starts.  In this new scenario, he would be asked to tap the screen again when the server starts his motion.  The addition of a clock (a shot clock, but visible only to the umpire) and that one extra tap is all that is required.

This way, the screen in front of the umpire would notify him of every possible time violation.  He would still be given leeway to call the time violation or not, perhaps ignoring the offense because of a long round of applause or a distraction on court.  With those records available after the fact, opponents and ATP supervisors would know whether time violations were called, especially when a player averages more than 25 seconds between points.

With these minor changes, we can hope for men’s tennis that moves along at a reasonable pace, thanks to unobtrusive rules that are equally applied to all players.