Category Archives: Rankings

Erratic Results and the Fate of Jerzy Janowicz

When Jerzy Janowicz defeated Victor Estrella in the first round at Roland Garros on Sunday, it was the Pole’s first win since Februrary, breaking a string of nine consecutive losses. Janowicz’s results have been rather pedestrian ever since his semifinal run at Wimbledon last year, yet the 720 points he earned for that single performance have kept his ranking in the top 25 and given him a seed at the Grand Slams.

As we’ve discussed many times on this site, occasional greatness trumps consistent mediocrity, at least as far as ranking points are concerned. The system rewards players who bunch wins together–Janowicz current holds about 1500 points, barely double what he earned from that single event last year.

In the short term, bunching wins is a good thing, as Janowicz has learned. But from an analytical perspective, how should we view players with recent histories like his? Does the Wimbledon semifinal bode well for the future? Does the mediocre rest of his record outweigh a single excellent result? Does it all come out in the wash?

It’s a question that doesn’t pertain only to Janowicz. While 48% of Jerzy’s points come from Wimbledon, 49% of Andy Murray‘s current ranking point total comes from winning Wimbledon. Another reigning Slam champion, Stanislas Wawrinka, owes 34% of his point total to a single event.  By contrast, for the average player in the top 50, that figure is only 21%. Rafael Nadal and Novak Djokovic are among the most consistent on tour, at 16% and 10%, respectively.

Since 2010, there has only been one top-40 player who earned more than half of his year-end ranking points from a single event: Ivan Ljubicic, whose 1,000 points for winning Indian Wells dominated his 1,965 point total. His top-16 ranking at the end of that year didn’t last. He didn’t defend his Indian Wells points or make up the difference elsewhere, falling out of the top 30 for most of 2011. Of course, he was in his 30s at that point, so we shouldn’t draw any conclusions from this extreme anecdote.

When we crunch the numbers, it emerges that there has been no relationship between “bunched” ranking points and success the following year. I collected several data points for every top-40 players from the 2010, 2011, and 2012 seasons: their year-end ranking, the percentage of ranking points from their top one, two, and three events, and the year-end ranking the following year.  If bunching were a signal of an inflated ranking–that is, if you suspect Janowicz’s abilities don’t jibe with his current ranking–we would see following-year rankings drop for players who fit that profile.

Take Jerzy’s 2012, for example. He earned 46% of his points from his top event (the Paris Masters final), 53% from his top two, and 57% from his top three.  (Corresponding top-40 averages are 21%, 34%, and 44%.)  He ended the year with 1,299 ranking points. At the end of 2013, his ranking no longer reflected his 600 points from Paris. But unlike Ljubicic in 2010, Janowicz boosted his ranking, improving 24% to 1,615 points.

The overall picture is just as cloudy as the juxtaposition of Ljubicic and Janowicz. There is no correlation between the percentage of points represented by a player’s top event (or top two, or top three) and his ranking point change the following year.

For the most extreme players–the ten most “bunched” ranking point totals in this dataset–there’s a small indication that the following season might disappoint. Only three of the ten (including Janowicz in 2012-13) improved their ranking, while three others saw their point total decrease by more than 40%. On average, the following-year decrease of the ten most extreme player-seasons was approximately 20%. But that’s a small, noisy subset, and we should take the overall results as a stronger indication of what to expect from players who fit this profile.

There’s still a case to be made that Jerzy is heading for a fall. He hasn’t racked up many victories so far this year that would offset the upcoming loss of his Wimbledon points. And his Wimbledon success was particularly lucky, as he faced unseeded players in both the fourth round and the quarterfinals. Even if he is particularly effective on grass, it’s unlikely the draw will so heavily favor him again.

But however a player earns his disproportionately large point total, the points themselves are no harbinger of doom. On that score, anyway, Janowicz fans can expect another year in the top 25.

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Filed under Jerzy Janowicz, Rankings, Research

Margin of Error Podcast: Episode Fourteen with Colin Davy

A new podcast is out!

Amy and I are joined this week by Colin Davy, inventor of the Advanced Baseline ranking system. You can find his writing at SB Nation. We recap the week in tennis, preview the big events in Madrid, and delve into predictive analytics with Colin.

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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Filed under Aging trends, Margin of Error podcast, Rankings

New Ranking Maps and Charts

I’m excited to share with you a couple of new features I’ve been working on for TennisAbstract.com.

First is an interactive ranking map:

rankmap

The above map shows the geographic concentration of teenagers in the WTA top 1000.  Click through to the full-size map, and you can mouse over any country to find out how many players they have in that category.

More importantly, you can customize the map in a variety of ways.  Choose from either the ATP or WTA rankings, decide how deep you’d like to go in the rankings, and if you’d like, limit the age range.  It’s a great way to see which countries are most dominant on each tour, and it’s also an opportunity to visually investigate which nations are likely to hold that power in the near future.

Next is an interactive ranking history chart:

rankchart

This chart shows ranking points for the big four over the past three years.  Again, if you click through to the full-size map, you’ll get more features: mouse over any line to see the date and the player’s ranking points at the date.

Like the map, the ranking chart is fully interactive.  You can select anywhere from one to four players–for now, only in the ATP top 100–choose a timeframe, and select either ranking or ranking points.

One option I want to call you attention to is one of the timeframes: “Year-end (by age).”  Here, instead of dates, the horizontal axis shows ages.  For instance, this graph shows the big four’s year-end rankings at each age.

Enjoy!

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Rafael Nadal, Top Twosomes, and the Future

The only match that either Rafael Nadal or Novak Djokovic lost in London was the final, when Nadal fell to Djokovic.  It was a good summary of the season as a whole.  The top two weren’t undefeated for the entire season, but they might as well have been.

Between them, Rafa and Novak lost only 16 matches this year, six of them to each other.  Fittingly, they split those six matches.  No single player poses a serious threat to their dominance.  Only Juan Martin del Potro defeated both this year, and he lost his five other encounters with the top-ranked duo.  The injured Andy Murray remains only a wildcard, having split Grand Slam finals with Djokovic this year but without having played Nadal since 2011.

Barring a huge upset loss in Davis Cup, Djokovic will end the season with the best-ever winning percentage for a #2-ranked player.  His 88.9% just edges out the 88.7% posted by Nadal in 2005, when he finished second to Roger Federer.  In the last thirty years, only five other #2’s won at least 85% of their matches.

Taking these six prior pairs as the best single-year twosomes the ATP has recently produced, it’s surprising to see what happened to them the following year.  In three of those seasons, neither of the ultra-dominant duos finished the next season at #1.  A third player overcame them both.

Here is the list of the seven most dominant twosomes of the last thirty years, along with their year-end rankings 12 months after the end of their notable seasons (Nx):

Yr  #1              W-L    Nx  #2              W-L    Nx  
83  John McEnroe    62-9    1  Mats Wilander   74-11   4  
85  Ivan Lendl      83-7    1  John McEnroe    72-10  14  
87  Ivan Lendl      70-7    2  Stefan Edberg   76-12   5  
89  Ivan Lendl      80-7    3  Boris Becker    58-8    2  
05  Roger Federer   81-4    1  Rafael Nadal    79-10   2  
12  Novak Djokovic  75-12   2  Roger Federer   74-13   6  
13  Rafael Nadal    76-7    ?  Novak Djokovic  72-9    ?

In 1988, Mats Wilander overcame both Ivan Lendl and Stefan Edberg to claim the #1 position.  In 1990, it was Edberg who leapfrogged Lendl and Boris Becker.  This year, of course, Nadal reclaimed the top spot from last year’s top two of Djokovic and Federer.

Those of us who watched the Tour Finals for the last week might find it hard to imagine that anyone–certainly not any of the other six men in London–would outperform either Rafa or Novak over the course of a season.  But injuries strike, slumps take hold, and–unlikely as it may seem in 2013–young players emerge and dominate. For all of the radical changes in the game since the late 80s, these precedents serve as an important reminder of the unpredictability of tennis.

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Filed under Forecasting, Novak Djokovic, Rafael Nadal, Rankings

If Rafa Only Plays on Clay

Since suffering the injury that would lead him to miss the second half of 2012, Rafael Nadal has said that he may have to cut back his tournament schedule so that he plays fewer matches on hard courts.

For someone who wants to remain at the top of the game, that’s a tough ask.  The majority of ATP ranking points come from hard-court tournaments.  If Rafa stuck to the clay, he would only be able to contest one of the four majors.

Becoming a full-time clay courter would almost certainly knock Nadal out of the running for world #1.  (As well as give him plenty of R&R in Mallorca.)  But how bad is it?  Let’s consider the possibility that in some future season, he only plays on clay.

Here is a possible 2013 schedule for a clay-only player, along with each event’s ranking points.  Three 250s are on this schedule, placed to provide warm-ups after each multi-week layoff:

20-Feb  Buenos Aires   250   
27-Feb  Acapulco       500   
09-Apr  Casablanca     250   
16-Apr  Monte Carlo    1000  
23-Apr  Barcelona      500   
07-May  Madrid         1000  
14-May  Rome           1000  
28-May  Roland Garros  2000  
09-Jul  Stuttgart      250   
16-Jul  Hamburg        500

If Rafa ran the table and won all of those events, that’s 7000 ranking points (only two of the 250s would count).  Unless the rest of the field becomes much more level, that won’t be good enough for the #1 ranking.  But it is a greater point total than Rafa has right now, and it would keep him in the top four.  Even averaging finalist points for these 10 events would allow him to remain in the top eight.

(Getting credit for those tournament wins would be a little trickier.  Players are required to show up for at least 4 500-level events, including one after the US Open.  If you only play on clay, there are no options.  To avoid the dreaded “zero-pointer” for not playing, Rafa might have to contest, say, Valencia.  However, points from those events no longer automatically count as one of a player’s top 18 events, so as long as the requirement was met, Rafa’s six non-slam, non-required-Masters events could be Monte Carlo, Acapulco, Barcelona, Hamburg, and two 250s.)

In practice, it’s tough to imagine that Rafa (or anyone else, short of Alessio Di Mauro) would avoid hard-court events entirely.  Much more likely is a scenario in which he plays all the clay court events possible and competes in hard-court events only when he feels sufficiently healthy.  That might mean an occasional semifinal run; it probably also means more second-round exits.

As unlikely and unusual as it would be, the all-clay schedule may be Nadal’s best route to setting more records.  With fewer injuries and much more rest, it’s easy to imagine him racking up another four or five French Open titles, along with perhaps ten more Masters crowns.  It would be an unusual career trajectory, to be sure, but it would also generate more fodder for the next ten years of GOAT debates.

 

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Filed under Rafael Nadal, Rankings

The Case for the Race

Last week, Peter Bodo argued in favor of giving the ATP year-to-date “Race to London” more weight over the traditional rolling 52-week ranking.  It’s a relevant point right now, when Roger Federer leads in the 52-week tally, but Novak Djokovic dominates in the year-to-date numbers.

In other words, Fed is racking up more records at #1 while Djokovic will almost certainly go in the books as the top player of 2012.  Bodo doesn’t go far enough: The old-fashioned rankings are weird, confusing, and–why stop there?–bad for tennis.

In most of the world’s most popular sports, everybody starts the year with a clean slate.  Imagine if a baseball team opened their schedule having to “defend” their previous year’s April winning streak.  Or if your favorite football team started the season seventh in their division.  This is essentially what happens when the ATP heads to Australia in January, altering rankings only when players do something different than what they accomplished last year.

Not only does this make it hard too root for underdogs in tennis, it makes it hard for the underdogs themselves.  You may not pity Bernard Tomic, but he surely spoke for many mid-pack players when he spoke about the mental challenge of defending points, not just beating world-class tennis players.  In other sports, hope springs eternal.  In tennis, it’s an immense struggle to crack the top 20 for a single week.

The greatest advantage of the Race is that it is so easy to understand.  Tomas Berdych reached the semifinals last week, so he gets 360 points.  Simple as that.  No comparison to last year’s totals, no concern about whether points are going on or coming off at a stagger from last year because of the Olympics, and–blessedly–nary a mention of zero-pointers.  Tennis rankings will always be more than simply incrementing the win column, but this is pretty close.

Bodo cites the unpredictability of the turn-of-the-century Australian Open as a reason why the Race didn’t catch on.  It doesn’t make sense to have Petr Korda atop much of anything, right?  In fact, that’s the beauty of it.  The 52-week rankings simply entrench the Big Four in our minds, while an emphasis on the race would make us think twice the next time a Korda, or a Marcos Baghdatis, or a Marin Cilic, makes a January splash.  Fans are smart enough to realize that leading the rankings early in the season isn’t the same as finishing at the top.

Some version of the 52-week ranking system will never go away, and that’s how it should be.  It’s purpose is to rate players–for seeding, and even more importantly, for tournament entry.  As I’ve written at length, it’s not a very good system for that purpose.  If we focused on the Race instead, the tournament entry methodology could become much more sophisticated and do a better job of putting the best players on court every week.

With its increasing focus on qualification for the Tour Finals, the ATP has taken some big steps toward presenting tennis as a high-stakes, year-long season, not merely a disjointed mishmash of events competing for attention.  Highlighting the Race rankings would make for much more spectator enjoyment.  It might even open the door to more important discussions of the chaotic tour schedule, eventually offering fans a coherent tennis season to follow every week.

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The Ever-Expanding Top Ten

Tennis fans talk about “cracking the top ten,” “top ten scalps,” and “top ten talent,” suggesting that this ranking milestone is a failsafe marker of the current elite.  While the top ten isn’t quite the same as the big four, the connotation is that the top ten is a class above.

Yesterday, Juan Monaco joined that group.  His Hamburg title earned him the 500 points to put him over the top, capping the best 52-week span of his career.  Since this time last year, he’s played five finals, won three titles, and reached the semis at the Miami Masters.

Job well done, Pico: We can now add you to an illustrious list featuring such names as Mikhail Youzhny, Nicolas Massu, Radek Stepanek, Arnaud Clement, and Marcos Baghdatis.  Kind of like an Olympic medal, an appearance in the top ten is something they can never take away from you.

As my snark implies, the top ten mystique is misplaced.  Sure, a berth in the top ten is an impressive accomplishment.  For that matter, a spot in the top 100 is far out of reach of mere mortals.  But with so many top-tenners hanging around, there’s barely enough mystique to go around.

Any given week, of course, there’s only room for ten men in the top ten.  But the last few spots are–and always have been–a revolving door.  At any given time, there are a staggering number of past, present, and future top ten players in the active ranks.

In fact, of the 146 players ever to reach the ATP top 10, 36 of them are in this week’s rankings.  A few, such as Massu, Thomas Muster,  and Fernando Gonzalez are retired (or might as well be).  But that still leaves more than 30 “top-tenners” among active players.  Even that doesn’t tell the whole story.

For a fuller perspective, head back a decade to the 2002 end-of-year rankings.  In December of that year, 70 of the men who appeared in the ATP rankings would, at some point in their career, crack the top ten.  If we set aside youngsters like Monaco and Rafael Nadal who were on the way up in late 2002, we find that of the top 100 on December 16, 2002, 47 could write “former top-ten player” on their Wikipedia pages.

Dwell on that for a moment.  Nearly half of the top 100 had this elite status.  You could nearly fill the Paris Masters draw with past, present, and future top-tenners.

Ten years from now, the same will probably be said about the class of 2012.  “Only” 28 of the current top 100 have spent time in the top ten, but for many of the other 72, there’s plenty of time to add to the list.  It seems a given that Milos Raonic, Bernard Tomic, and Kei Nishikori will at some point crack the top 10, while players like Alexandr Dolgopolov, Ryan Harrison, Grigor Dimitrov, Vasek Pospisil, and Cedrik Marcel Stebe are poised to follow them to the top.

Your list may be different than mine, but the details don’t matter.  A year ago, most people wouldn’t have guessed Monaco would crack the top 10.  When Janko Tipsarevic was ranked around #50 on his 26th birthday, no one imagined he’d spend months at #8.  To say that Dimitrov, or Pospisil, or David Goffin is a future top-tenner doesn’t mean he’s going to take over the sport and beat all comers, it just means that he’ll put together a year with a couple of 250 titles and a handful of solid wins against other top players.

Next time someone offers you to bet you that so-and-so won’t ever reach #10 in the world, it’s worth careful consideration.  The top ten is bigger than it sounds.

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Three Simple Ways to Improve the ATP Ranking System

Rafael Nadal‘s two-year ranking system would favor a few veterans at the expense of everyone else.  My algorithm is too complex for players and fans to use on a weekly basis.  But there is always an undercurrent of dissatisfaction over the current system.

The rankings serve two main purposes, each of which we must keep in mind as we think through a better system:

  • Entertainment. The fans want to know who’s number one.  No system will ever be perfect, but if the ranking system told us that Nadal outranked Djokovic despite losing to him several times in a row, the system would lose credibility.
  • Tournament entry. Rankings determine who gets direct entry into tournaments.  A biased ranking system would keep stronger players out of tournaments while letting in lesser players.

A system that is good for one of these purposes is generally good for the other.  In an ideal world, the rankings would show us who is playing the best right now, carefully defining “right now” to avoid an unnecessary focus on current hot streaks.  Another way to look at is that the rankings should be as predictive as possible.  If underdogs are constantly winning, that doesn’t mean tennis is a sport full of triumphant underdogs, it means we’re ranking players incorrectly!

The current system isn’t that bad.  There are three main problems, however:

  1. Last week is equal to last year.  The winner in Miami this week will gain 1000 points.  Those 1000 points will be counted in his ranking next week, in six months, and in 51 weeks. In 53 weeks, though, he’ll have zero points.  If we’re trying to measure how good he is, a tournament 51 weeks ago isn’t nearly as informative as his tournament last week.  And if we insist on using his result from 51 weeks ago, why not his result from 53 weeks ago?
  2. Surfaces are interchangeable.  Milos Raonic won a slew of matches on indoor courts last spring, which earned him a seed at the French Open.  Now, I love Milos, but did he really deserve a seed at the French, despite virtually no professional experience on clay?  Performance on one surface translates to other surfaces to some extent, but (obviously!) all surfaces are not created equal.
  3. All opponents are equal.  In the Miami third round, Andy Roddick beat Roger Federer … then lost.  He’ll get 90 points. Kei Nishikori beat Lukas Rosol … then lost. These sorts of differences sometimes even out over time, but must we trust that they will?  Roddick’s achievement this week is much more impressive than Nishikori’s, and should be treated as such.

We can fix all of these problems with simple arithmetic, making tweaks to the system that any player or fan can understand.

In these solutions, the exact details don’t matter.  The most important thing is simply to acknowledge that not all matches are equal.

  1. Last week is worth more than last year.  In my system, last week is worth a little bit more than the week before, which is worth a little bit more than the week before that, and so on.  Here’s a simple way to incorporate that into the ATP system: After four months, tournaments are worth only 80% of their original points.  After eight months, tournaments are worth only 60% of their original points.  That way, the drop off is more gradual, and Indian Wells is worth more than, say, the 2011 Rome Masters.  If Nadal still wants two years, this can easily be extended to cover two years of results–after a year, 45%; after 16 months, 30%, after 20 months, 15%.  Now everybody’s happy!
  2. Separate surfaces, separate rankings.  There will always–and should always–be a single most important ranking list, encompassing all surfaces.  But for tournament entry, why not do better?  For example, create a clay list by doubling the point value of all clay tournaments and leaving the others alone.  David Ferrer and Carlos Berlocq will rise; John Isner and Kevin Anderson will fall.  Any tennis fan knows this happens, so tournaments should determine entry this way, as well.  After all, Wimbledon has long used this sort of approach for seeding, if not for direct entry.
  3. Bonus points for beating top players.  The WTA used to do this, and it’s the least straightforward of my suggestions.  It’s so important, though, that a little complexity is worth a lot.  Let’s say 100 points for a win over anyone in the top 3; 75 points for beating anyone ranked 4, 5, or 6; 50 points for a win over anyone else in the top 10, 30 points for beating anyone ranked 11-15, and 10 points for a win over anyone ranked 16-20.  Mega-upsets like those scored lately by Isner, Roddick, and Grigor Dimitrov tell us something important, and the rankings should listen.
This is all stuff you can do on a calculator–nothing is more complex than the rules governing protected rankings or zero-pointers.  Young players will see their rankings rise more quickly once they begin beating the top guys.   All players will get into tournaments (and earn seeds) on surfaces where they have had more success .  And the fans will have a more accurate ranking system both to rely upon and to fuel arguments about which players are really better.

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Filed under Harebrained schemes, Rankings

The Fatal Flaw of Nadal’s Two-Year Ranking System

Now that Rafael Nadal has resigned from the ATP player council–apparently because no one took his two-year ranking plan seriously–we’re likely to hear a bit more about this alternate approach.

Presumably, Nadal’s method would count the last 104 weeks (two years) of results instead of the last 52, as is currently the case.  As far as I know, he isn’t pushing for any other adjustments.  As long as that is the case, the rest of the council (and the ATP in general) is right to ignore Nadal’s plan: It would do significant damage to the sport, without much in the way of benefits.  It would drastically slow the rise of young players, but change little for guys at the top.

Ultimately, the question is over the purpose of the ranking system.  If it is to reward past performance, a two-year ranking system may be appropriate.  If it is to rank competitors by their current level of play, treating a tournament 22 months ago the same as last week’s tournament is flat-out wrong.

Consider what the present ranking system tells us.  By equally weighting tournaments over the last 52 weeks (with more points for more important events, of course), a player’s ranking is the average of how good he has been over the last 52 weeks–in other words, it’s a approximation of how good he was 26 weeks ago.  For most players, this is a decent estimate of how good they are right now.  If we go to a two-year system, the rankings would be an estimate of how good players were one full year ago.  Yikes.

The most obvious casualties of such a system are young players (or any players, really) on the way up.  Even with the current system, the rankings take some time to catch up with a rising star like Bernard Tomic or Milos Raonic.  When Raonic had his great run in early 2011, the rankings were still counting a bunch of challenger results from one year earlier.  In a two-year system, Raonic’s more recent results would count for even less.  It would take twice as long for such a player to establish himself.

The clear beneficiaries, of course, are the opposite type of competitor: established players who are declining or injured.  If a player is consistently good, it really doesn’t matter how the ranking system is calculated–just about any way you slice it, Djokovic, Nadal, Federer, and Murray would be the top four.  But the players who benefit are the ones who posted good results between 52 and 104 weeks ago, and haven’t done nearly as well since.  Right now, that means injured players like Robin Soderling, and declining players like Andy Roddick and Fernando Verdasco.

Should Roddick and Verdasco continue to be rewarded for their play in 2010?  To me, anyway, the answer is a clear “no.”  Even with Roddick’s sharp decline, he will probably still earn a seed for the French Open.  Does he deserve more than that?

But what about Soderling?  He hasn’t played since June, and his ranking has fallen to #30.  Unless he returns in the next three months, he’ll fall off the list altogether.  If there is a case for Nadal’s system, this is it.  But the ATP already has two methods in place to protect players like Soderling: protected rankings (PR) and wild cards.  Players injured for a certain length of time are able to use a PR (equal to their ranking when they last played) for entry to a set number of tournaments.  Until recently, Tommy Haas was still using a PR of 20.  Soderling would have a PR that would get him into enough tournaments to rebuild his ranking, assuming he comes back with any semblance of his previous form.

Of course, there’s also the wild card.  When Soderling returns, even if he is unranked, every 250- and 500-level tournament would hand him a wild card without a second thought.  This makes PRs even more valuable than the ATP intended them to be: Haas, for example, has been able to use his PR of 20 for so long because many tournaments gave him wild cards.  He could save the PR for when he needed it.

The only disadvantage to PRs and WCs is that these players aren’t seeded.  But really, after sitting out for a year, does a player deserve safe passage to the third round?  I find it hard to believe that they do.  And if this is really such an important issue, perhaps a player such as Soderling could be granted the lowest seed (e.g. 32, at Indian Wells, Miami, or a slam) two of the times he uses his protected ranking.

To recap: A simple two-year system would retard the rise of young players, forcing them to prove themselves for twice as long as is currently the case.  It wouldn’t affect consistently good players.  It would help players on the decline who probably don’t deserve help.  And top players returning from injury have little problem entering tournaments; Nadal’s approach would just get them seeds.

But Jeff, doesn’t your ranking system use two years of results?

Yes, I was getting to that.  It’s crucial to distinguish between using two years of results (acceptable) and weighting all results equally (unacceptable).

The biggest problem with the ATP ranking system as is–and it would be an even bigger problem with a two-year system like Nadal’s–is that it treats long-ago tournaments as equal to yesterday’s tournaments.  The winner of the 2012 Indian Wells event has 1000 points on his ranking.  The winner of the 2011 Miami even has 1000 points on his ranking.  The winner of the 2011 Indian Wells event has … zero points on his ranking.

How a player performed 18 months ago, or 20 months ago, has some predictive value.  But not nearly as much as the predictive value of their more recent performances.  In slight support of Nadal’s case, this is particularly true of players returning from injury.  My system never removed Juan Martin del Potro from the top 10 or so; using a one-year system, the ATP rankings saw him drop far out of the top 100.

If you are to use two years of results, it is absolutely imperative to differentiate between recent results and older results.  In fact, even a simple approach of this sort would improve the current 52-week system.  My algorithm weights results one year ago about half as heavily as last week’s, and two years ago roughly one-quarter as heavily.  The weighting is not simple, and thus would be inappropriate for the ATP system, which must be easily understood by both players and fans, but it points the way toward simpler solutions that might work.

That’s enough for today.  Check back tomorrow, when I’ll go into more depth about how the current ranking system can be improved.

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Filed under Harebrained schemes, Rafael Nadal, Rankings

Hard Court Rankings: 6 March 2012

It’s been a while since I posted new rankings.  To help get us ready for Indian Wells, here are my latest hard court rankings.  They are considerably more predictive the the ATP rankings, by considering two years’ worth of matches, surface, location, age, and weighting recent results more heavily. If this is your first time, click here to read more about the methodology.

As usual, there are plenty of surprises.  Despite Federer’s defeat of Murray last weekend, Murray has overtaken Roger in my rankings–just barely.  My numbers take into account quality of opponent, so my guess is that Murray’s win over Djokovic in the semifinals put him over the top.

Because younger players improve faster, my rankings consider each player’s age.  As usual, you’ll find Tomic and Harrison ranked higher than in the ATP rankings.  The shock, though, is Denis Kudla, #70 in my system.  The ATP rankings have him barely inside the top 200.

On the flip side, these rankings demote several players who have racked up points at lesser events.  Isner is at #20 (in part because my system doesn’t count Davis Cup) and Bogomolov is all the way down at #66.

Here is the current hard-court top 100:

RANK  PLAYER                   PTS  
1     Novak Djokovic          7437  
2     Rafael Nadal            4560  
3     Andy Murray             3778  
4     Roger Federer           3757  
5     Juan Martin del Potro   2919  
6     Jo-Wilfried Tsonga      2663  
7     Tomas Berdych           2476  
8     Gael Monfils            2231  
9     Kei Nishikori           1943  
10    David Ferrer            1833  
11    Mardy Fish              1806  
12    Stanislas Wawrinka      1613  
13    Robin Soderling         1599  
14    Bernard Tomic           1543  
15    Milos Raonic            1486  
16    Marcos Baghdatis        1486  
17    Janko Tipsarevic        1449  
18    Marin Cilic             1424  
19    Richard Gasquet         1406  
20    John Isner              1314  

RANK  PLAYER                   PTS  
21    Florian Mayer           1274  
22    Gilles Simon            1265  
23    Alexander Dolgopolov    1259  
24    Marcel Granollers       1202  
25    Andy Roddick            1195  
26    David Nalbandian        1131  
27    Fernando Verdasco       1108  
28    Philipp Kohlschreiber   1083  
29    Feliciano Lopez         1050  
30    Jurgen Melzer           1019  
31    Viktor Troicki          1004  
32    Ernests Gulbis          1001  
33    Nicolas Almagro          986  
34    Samuel Querrey           982  
35    Juan Monaco              968  
36    Mikhail Youzhny          955  
37    Julien Benneteau         953  
38    Kevin Anderson           910  
39    Nikolay Davydenko        875  
40    Ivan Dodig               857  

RANK  PLAYER                   PTS  
41    Michael Llodra           852  
42    Ivan Ljubicic            817  
43    Mikhail Kukushkin        798  
44    Andreas Seppi            788  
45    Ivo Karlovic             773  
46    Jeremy Chardy            756  
47    Lukas Lacko              741  
48    Ryan Harrison            740  
49    Donald Young             739  
50    Denis Istomin            719  
51    Philipp Petzschner       717  
52    Guillermo Garcia-Lopez   704  
53    Cedrik-Marcel Stebe      691  
54    Grigor Dimitrov          681  
55    Sergey Stakhovsky        669  
56    Santiago Giraldo         661  
57    Adrian Mannarino         654  
58    Andrei Goloubev          648  
59    Radek Stepanek           645  
60    Igor Andreev             645  

RANK  PLAYER                   PTS  
61    Steve Darcis             641  
62    Jurgen Zopp              640  
63    David Goffin             638  
64    Robin Haase              632  
65    Jarkko Nieminen          628  
66    Alex Bogomolov           620  
67    Lukasz Kubot             615  
68    Thiemo de Bakker         605  
69    Thomaz Bellucci          603  
70    Denis Kudla              601  
71    Olivier Rochus           588  
72    Daniel Brands            581  
73    Alejandro Falla          575  
74    Dudi Sela                570  
75    Xavier Malisse           565  
76    Richard Berankis         564  
77    Dmitry Tursunov          558  
78    Igor Sijsling            558  
79    Vasek Pospisil           557  
80    Benoit Paire             548  

RANK  PLAYER                   PTS  
81    Matt Ebden               544  
82    Laurynas Grigelis        523  
83    James Blake              517  
84    Matthias Bachinger       511  
85    Tobias Kamke             510  
86    Marius Copil             510  
87    Benjamin Becker          504  
88    Ryan Sweeting            500  
89    Jesse Levine             498  
90    Roberto Bautista         483  
91    Michael Zverev           480  
92    Flavio Cipolla           480  
93    Fabio Fognini            479  
94    Jesse Huta Galung        478  
95    Michael Berrer           475  
96    Grega Zemlja             470  
97    Yen-Hsun Lu              465  
98    James Ward               460  
99    Nicolas Mahut            452  
100   Ruben Bemelmans          449

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