Margin of Error Podcast: Episode Twelve

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Amy and I talk Monte Carlo, Wawrinka, Djokovic, Nadal, Fed Cup, Aga, Cibulkova, Barcelona, Stuttgart, and Halep. We also take an early look at the women’s Roland Garros field.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

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Margin of Error Podcast: Episode Eleven

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Amy and I reluctantly discuss the incredibly boring week of professional tennis that just happened, then gladly turn to the near future, including the Monte Carlo Masters, this weekend’s Fed Cup semifinals, and the upcoming ATP clay season as a whole.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

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Margin of Error Podcast: Episode Ten

A new podcast is out!

Amy and I have plenty to say about the Davis Cup World Cup quarterfinals, and also recap last week on the WTA. We look ahead to Casablanca, Houston, Katowice, Bogota, and the clay season in general.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

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Margin of Error Podcast: Episode Nine with Carl Bialik

A new podcast is out!

Amy and I are joined by fivethirtyeight.com’s lead news writer Carl Bialik, reprising his role from episode one. He recently wrote about John Isner’s home court advantage, and we spend most of our time ranging over the many unique qualities of the American #1.

We also recap the Sony Open and preview Charleston, Monterrey, and the Davis Cup World Cup quarterfinals.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

If you’ve been enjoying the podcast, please leave us a review in the iTunes store so that others are more likely to find us. If you haven’t been enjoying the podcast … well, I’m sure you have more important things to do than write a review.

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Facts, Figures and Myths About Walkovers

Novak Djokovic advanced to the final of the Miami Masters today when Kei Nishikori withdrew from the event due to injury. Oddly, it was the second match at the Sony Open that Djokovic didn’t have to play, as Florian Mayer pulled out before their scheduled third round match.

It’s a rare occurrence in professional tennis–so rare that it had only happened once since 1968, when several players benefited from multiple walkovers at the French Open. In Miami two years ago, Andy Murray also skipped his third round and semifinal matches, as both Milos Raonic and Rafael Nadal dropped out due to injury.

The fact that it was Djokovic who got the free pass immediately gave rise to all sorts of speculation. Will the lack of match play hurt the Serbian? Does Novak get more walkovers than most? Are opponents more likely to withdraw if they’re facing a top player?

Let’s take these questions in order. I addressed a similar issue a couple of years ago in this post. Walkovers are rare, but the available evidence suggests that there’s no positive or negative effect from winning via withdrawal. A player’s chances of winning his next match are roughly what they would’ve been anyway.

Djokovic does gain from walkovers more often than the average player, but he’s far from the top of the list. Opponents have withdrawn five times in his 695 matches, good for 0.7%, roughly the same rate as opponents of Murray, Nadal, Roger Federer … and Donald Young and Dmitry Tursunov. Jo Wilfried Tsonga has benefited from six walkovers in 432 matches, a 1.3% rate, highest among tour veterans.

Top players win by walkover more often than others–but as we’ll see in a moment, it isn’t because they are top players. It’s intuitive to figure that mildly injured players are more likely to take the court if they think they have a better chance of winning, but the evidence suggests there’s little, if any, effect.

Men ranked in the top five win by walkover 0.6% of the time, while those in the next five get free passes 0.3% of the time, and most of the rest of the pack benefits at the tour average rate of 0.2%–once every 500 matches. (All of these aggregate rates are based on tour-level matches from 1991 through 2014 Indian Wells.)

For the most part, top players get walkovers because they hang around until the late rounds of tournaments. Walkovers occur at the highest rate in the quarterfinals of events, when 1.1% of matches end before they begin. Round-of-16 contests are almost as bad, at 1.0%, and semifinals are also considerably more walkover-prone than average, at 0.6%.

When we take these dangerous middle rounds out of the equation, the number of walkovers shrinks, as does the difference between top players and the rest of the pack. Less than 0.15% of pre-R16 matches end in walkover, and the rate at which top-five players benefit from them falls to 0.4%. That’s still more frequent than the rate for the rest of the field, but keep in mind the tiny numbers we’re dealing with here. It’s 13 walkovers in over 3000 matches. Take away five of those withdrawals–roughly two per decade–and the top five would benefit at the same rate as players ranked 16-20.

It’s not as interesting a narrative, but it appears that players usually withdraw when they are too injured to compete, and that’s most likely to happen midway through a tournament. The highest-ranked players benefit–because of their previous success on the court, not their intimidating influence off of it.

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Margin of Error Podcast: Episode Eight

A new podcast is out!

Amy and I bring you up to date with the action in Miami. We also pay tribute to Samuel Groth on the event of his first Challenger title and give a resounding “meh” to talk of a fifth slam.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

If you’ve been enjoying the podcast, please leave us a review in the iTunes store so that others are more likely to find us. If you haven’t been enjoying the podcast … well, I’m sure you have more important things to do than write a review.

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Disorder of Play

Imagine you’re a rabid Chicago Cubs fan (sorry), and you’re looking forward to the season starting in a couple of weeks. You’re thinking of making a road trip to see your favorite team. You go to the Yankees website, and all you can find are some vague references to a big series in St. Louis in May. Nothing more.

You check out MLB.com and find a story about the matchup between the Cubs and White Sox, but it’s mostly about last year. Finally you start checking the websites for other MLB stadiums, and you discover that the Cubs are scheduled to play in Milwaukee for three days in June. You consider checking another couple dozen sites and finally give up.

Baseball fans know just how ridiculous that is–you can find a Cubs schedule in any of hundreds of places, with clickable links to every other MLB team’s slate for the season. You can see a list of every Opening Day matchup or, if you want, every game scheduled for the 5th of September.

Yet this fictional scenario of fruitless schedule-hunting is exactly what tennis fans face every week of the season. It’s easy to find out where tournaments will be held, but often impossible–and always irritating–to establish who will be playing. If you want to know what the next few weeks look like for your favorite player (especially if your favorite player isn’t named Roger, Rafa, Novak, or Andy), good luck. Patience is a virtue, I guess.

Unlisted lists

Players formally commit to tour events several weeks ahead of time. Each tournament has an entry deadline (top-tier events are six weeks in advance, Challengers three weeks), and once entries are in, we have what is called–you guessed it–an entry list. You can see the list for the ATP Houston event here, since the tournament organizers chose to publish it. Not all events do.

And even when they do, they rarely keep them up to date. Throughout the several weeks between the initial list and the beginning of qualifying rounds, players withdraw and alternates enter the mix. Especially at the 250 level, it’s not uncommon for 10 or more alternates to find their way into the main draw.  But with an old list (if there is a list at all), how to know whether Tim Smyczek or Dominic Thiem or Dudi Sela or Somdev Devvarman is going to be there?

Making matters worse, Wild Card entries–players who are chosen in part to increase fan interest at an event–are often published elsewhere, for instance in a press release. 18 days from the opening of the tournament, Houston hasn’t said anything about who any of those players will be. (Though if I were a betting man, here’s where I’d put my money.)

Usually, if you’re willing to put in some effort and you want to know a specific fact–Is Bernard Tomic going to play Monte Carlo? Is Tommy Robredo going to defend his title in Casablanca?–you can find it. But is that really the best the ATP can do? Again, think of the scenario in which it takes a super sleuth to find out where the Cubs will be playing in a month.

Help us become bigger fans

Sporting organizations thrive on big fans, the ones who travel to events (paying for lots of tickets), pony up for year-long subscriptions to streaming services, and stock up on branded merchandise. These fans want to know what’s going on all the time, and they care about more than just the two players who might appear on the front page of the newspaper.

It would be so simple to make available an actual schedule, like other sports started doing back in the 19th century. In fact, before the ATP password-protected their entry lists, I did just that. Here’s a simple page that shows everyone who was on an entry list in a six-week period, along with links to the lists for each event.

That information is out there. It’s an insult to fans to hide it. We want to get excited about our favorite players–both the ones who are guaranteed a seed and the ones who are holding out hope of a spot in the main draw. We deserve better.

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