Between The Lines
January 15, 2010
Contact Ray Bowers
Latest Between The Lines Article
Between The Lines Archives:
2003 - 2015
August 1998 - 2003
1995 - May 1998
Do You Want To Be A Better Tennis Player? Then Sign Up For A Free Subscription to the Tennis Server INTERACTIVE|
You will join 25,000 other subscribers in receiving news of updates to the Tennis Server along with monthly tennis tips from tennis pro Tom Veneziano that won't be found on the web site.
Best of all, it is free!
Top Pros (Women)
||EXPLORE THE TENNIS NET:
Preview Australian Open 2010
by Ray Bowers
Once again Australia introduces a new tennis year. Along with a quality of tennis perhaps never before seen, the 2010 edition of Australian Open will bring two weeks of drama, glory, and misfortune among the world's superstars, all carried by modern communications worldwide. The magnificent setting at Melbourne Park will include two convertible-roof stadia, which were closed several dates last year amid extreme daytime temperatures.
The Plexicushion courts, introduced in 2008, give servers only a slightly greater advantage and provide only a slightly faster horizontal bounce than did the former Rebound Ace surface. We can therefore expect that Australian Open 10 will favor the strong server and the more aggressive player, though not quite to the extent seen at U.S. Open and assuredly not to the extent seen at Wimbledon. A player who is defensively oriented will probably find the courts too fast for comfort, especially after the top layers have been smoothed slightly from usage in the early rounds.
The men's and women's champions at the Open will earn substantial leads in the points races for 2010. Last year's male winner at Melbourne Park, Rafael Nadal, was able to build on his early lead for several months thereafter, into the clay-court season, before slipping behind the year's eventual champion, Roger Federer. The women's singles winner at Melbourne last year was Serena Williams, who like Nadal would lose her early lead in the year-to-date race to Dinara Safina during the spring. But the powerful American would eventually finish the year at #1 -- the first Australian Open women's champion since Hingis in 1998 to do so.
Data from the late rounds of Slams show that among top male pros, greatest success occurs at age 23 on average. Probably most players continue to improve their skills thereafter, but Slam results on average begin to fall off at that age, probably reflecting the accumulating effects of injuries and also the strength of younger cohorts as the game advances. Those superstars able to sustain or raise their level of achievement after age 23 are defying the averages. (See Footnote 1.) Although both year-end champions for 2009, Federer and Williams, were well beyond the statistical peak age, the average age during 2009 of the year's top eight players, both male and female, was 24.
Here, we survey candidates at Melbourne while grouping them by age. Our focus remains in evaluating the possible winners, but we also seek perspectives on the linking of age and achievement.
MEN'S SINGLES -- THE ELDERS
We begin with the group aged 28 and above, the Elders.
Roger Federer, 28, has sustained his Slam performances magnificently after passing 23. Last year he reached the final rounds of all four Slams, winning Garros and Wimbledon, and again finished as world #1. His 2009 triumphs were especially remarkable in that they came after yielding the top place in 2008 to Rafael Nadal when Federer became weakened amid an early-year diagnosis of mononucleosis.
But in the year's final months the victories again became fewer and more difficult for Roger. His five-year run as U.S. Open champion ended in a five-set final-round loss to the tall Argentine striker del Potro, then aged 20. Then there were losses to Djokovic at Basel, to Benneteau at Paris Indoors, and four three-set struggles at the year-ending event in London, including losses to del Potro and Davydenko. Roger played many magnificent points on these occasions and he unquestionably remains among the game's elites, but the reserve of greatness that once seemed always available in turning aside difficult opponents was plainly no longer at hand.
Was it just a passing dip, suggesting that we should make Roger the favorite to win at Melbourne? He has won Australian Open three times, and he shows W-L record there of 37-3 starting in 2004. He reached the final round last year, losing a memorable five-setter to Nadal. But at age 28 and following a disappointing fall season, the doubts will not go away. We estimate Roger's chances for winning the tournament longer than in previous years: odds 5-1.
Two months older than Federer is Nikolay Davydenko, the swift and slender superstar resident of Volgograd, whose magnificent play in winning in London in late 2009 produced his most distinguished career laurel. If Nikolay can indeed sustain the superb movement to the ball and accuracy of hitting shown against young del Potro in the London final, he is capable of beating anyone. Nikolay finished 2009 at #6 despite a long absence for heel and leg injuries, and he started 2010 by winning the tournament at Doha, Qatar, where he again defeated both Federer and Nadal, as at London. Davydenko's odds at Melbourne, 8-1.
Fernando Gonzalez, 30, and Radek Stepanek, 31, finished last year at #11 and #12, respectively. Gonzalez has been an erstwhile performer within or close to the top 20, runner-up at Melbourne Park in 2007. Stepanek had broken into the top 20 only once before, but he lifted his results in late 2009, showing an excellent capability in a net-attacking style. Both men missed qualifying for London by narrow amounts, but while Gonzalez seems to have found his permanent plateau, Stepanek's late-season surge along with a nice run at the Brisbane tune-up suggest possible upward movement in 2010. Odds: Gonzalez, 90-1, Stepanek, 90-1.
Several other veterans created splash at times in 2009, and will be among the seeded list at Melbourne -- Tommy Haas, 31, Ivan Ljubicic, 30, and Lleyton Hewitt, 28. Their odds for winning the tournament are long -- 100-1 or longer in each case.
THE POST-PRIME GROUP
The age group 25-27 seems less rich than the Elders. Might the years of dominance by Federer over these slightly younger players explain the group's faint footprint?
The group's leaders are three stars just outside the current elite. Andy Roddick, 27, who finished 2009 at world #7, shows one Slam in his career resume -- the U.S. Open crown in 2003 when he was barely 21. Andy's magnificent serve has never left him, and improvement in his strong ground-oriented power game and in his once-shaky net play has been evident over the years. Last year he was finalist at Wimbledon, beating Murray and carrying Federer to five sets. Andy's summer and fall were disappointing, marked by late-year knee trouble, but he won the Brisbane tune-up, losing only one set and winning ten, five of them in tiebreakers.
Closely ranked with Roddick is Fernando Verdasco, 26, the lefty from Madrid. Verdasco reached the semis at Melbourne last year, where he compiled a fine run prior to a memorable five-set semi-final loss to Nadal. He scored good wins in the tune-up at Kooyong just before the current draw.
The third member atop the Post-Primes is the sullen Swede, Robin Soderling, 25, whose dazzling rocketry ended the perfect record of Nadal at Garros last year and produced many strong appearances thereafter. When his forehand and backhand sizzlers find the corners consistently, as happened on these occasions, Soderling is almost unbeatable. Elbow trouble inhibited his play in August but the fall results were again strong, including a close loss in the London semis.
I make odds for winning Melbourne Roddick at 30-1, Verdasco at 30-1, Soderling at 35-1. Meanwhile the Post-Primes also include Robredo and Ferrer of Spain, Simon of France, and Youzhny of Russia, all at 100-1 or longer except Robredo, who swept the field at Hopman Cup in January but then lost in his second match at Sydney, at 75-1.
THE PRIME-AGE GROUP
Here are the players aged 22-24, the Prime Agers -- the stars who are probably now at their peak. They include the three directly behind Federer in the rankings for 2009.
Rafael Nadal, now 23, will need to recover from his disappointing summer and fall 2009. After missing Wimbledon while resting his troubling knee and leg, Rafa scored no further tournament victories through year's end, though he reached the middle and late rounds fairly consistently. The ruthless and energetic extreme overspin seemed less vicious than in year's past, the adherence to the defensive style more rigid than seemed optimum. The knee remained unwrapped, the physique slightly trimmer than before, but the victories were harder in coming, the opponents no longer crumbling before Rafa's relentless weight of shot. At the London finale, Rafa played creditably but lost all three of his round-robin matches, all in straight sets. In January he beat Soderling at Abu Dhabi exhibition and lost closely to Davydenko at Doha. Odds at Melbourne for the defending champion: 9-1.
Novak Djokovic, 22, finished 2009 at #3, behind only Federer and Nadal for the third straight year. His bruising serving and stroking, beautifully controlled, along with his excellent court movement at height 6-3, place him the most likely of the Prime-Agers to break out upward. He validated his potential in winning Australian Open in 2008, beating Federer in the semis, Tsonga in the final, but he went out in extreme heat last year to Roddick. His showing was disappointing at the Kooyong exhibition tune-up. He holds a nice lead over Nadal in head-to-head play on hard courts (though not on clay). Novak's odds at Melbourne are 6-1.
Next behind Djokovic in the rankings is Andy Murray, also 22 and also 6-3, whose brilliant stroking and movement seem at least co-equal with Djokovic's. A year ago, after consecutive wins over Federer, he was my choice to win at Melbourne. But hard-court tennis is essentially an attacking game, and although Andy's defensive strengths are wonderful and although he can command extreme power at any instant, he often seems too wedded to patience, lacking in attacking mindset. Statistically, he and Nadal were about equal in 2009 as the most successful serve-returners in the pro game. He was upset this month by Robredo at Hopman Cup. Murray's odds at Melbourne: 12-1.
Two others, both born in France, both held back by injuries and inconsistency through their careers to date, have shown obvious raw potential for high success. Power-hitting and athletic Jo Wilfried Tsonga, now 24, although unseeded, bludgeoned his way to a final-round date with Djokovic at Australian Open 08, showing wins over Murray and Nadal enroute. At Kooyong 10 he defeated Soderling. Meanwhile Gael Monfils, 23, invariably displays dazzling mobility and athleticism amid excellent forehand, backhand, and serving power, along with a physique highly supple in movement and stroking. But like Murray, there is a disturbing over-preference for patience and defensive play. Odds at Melbourne: Tsonga 50-1, Monfils 50-1.
Our prime-age group also includes big-servers Tomas Berdych, age 24 at 6-5, and Sam Querrey, at 22 and 6-6. Berdych is now ahead but Sam is at the youngest end of the age group and has climbed more rapidly than Tomas. Jeremy Chardy, 22, has made impressive jumps in ranking annually. All three are at odds 100-1 or longer.
The magnificent ascent of Juan Martin del Potro, now 21 at 6-6, lifted him to the U.S. Open crown last summer and a year-end world ranking of #5. His improvement over the last year or so in serving, stroking, and movement were clear, so that his final-round loss to a sizzling Davydenko in London was surprising. The explanation lay in the incredibly high level attained by Nikolay on that day, perhaps accompanied by flatness by Juan Martin at the end of a demanding season.
There seems no doubt that del Potro is ready for higher success, certainly including a possible Australian Open crown in 2010. Last year he won four matches there prior to a humiliation administered by Federer. Juan Martin's odds at Melbourne this year: 7-1.
Another prodigy, with similar strengths and style to del Potro's, is the lanky Croatian player Marin Cilic, also now 21 at 6-6. Cilic won three matches at Melbourne last year before a four-set loss to del Potro, and did even better at the other hard-court Slam, U.S. Open, beating Murray and three others prior to another four-set loss to del Potro. But at #14 in the year-end ranking for 2009, he began 2010 with five wins over lower-ranked foes to win the tournament at Chennai, India. Odds: 40-1.
There is little doubt which of our four groups is the strongest. Here are each group's chances for providing the men's singles winner (numerically derived from the individual odds quoted above).
The odds quoted above were reached by subjective judgment, adjusted to reach overall probability of 1.0. The below predictions of likely match-ups from the official draw, however, rest on two calculations, as follows:
- The First Calculation measures each player's weighted performance in events of the past 12 months, where the weights depend on how successfully each event has predicted late-round results at the last nine Australian Opens.
- The Second Calculation measures past head-to-head results between the two players being considered.
In most cases, the two calculations agree as to the probable winner. (See Footnote 2.)
The leading contenders in each quarter are listed here in seeded order.
Federer, Davydenko, Verdasco, Simon, Hewitt.
Simon over Hewitt. Gilles Simon has the edge both in the 12-month performance and in the head-to head calculation, having won their only meeting of the last two years, at Miami 09.
Federer over Simon. Gilles won their two past meetings, both in 2008, both in split sets. But Roger's edge in the 12-month record is far too large. Federer.
Davydenko over Verdasco. Nikolay has a narrow advantage in the 12-month calculation, and a more significant head-to-head W-L margin of 2-0 in the last two years (and 6-1 lifetime).
Federer over Davydenko. This is among the closest of calls. Roger has a moderate edge in 12-month performance -- his score is 3.39 vs. Nikolay's 1.88, or a differential of 1.51 for Federer. But Davydenko has won their last two meetings, at London 09 and Doha 10, which are both heavily weighted in our calculations and are offset only slightly by Federer's win at Estoril 08. Nikolay's calibrated head-to-head edge comes to 1.26, a value only slightly lower than Roger's edge in the First Calculation. Federer to the Final Four.
Djokovic, Soderling, Tsonga, Robredo, Haas.
Haas over Robredo. The 12-month edge is narrowly Robredo's, but Haas's straight-set win over the other Tommy at Wimbledon 08 carries enough weight to swing the verdict to the veteran.
Djokovic over Haas. Tommy commands the last two head-to-head wins, both on grass, both split-setters and therefore somewhat devalued as predictors here. Djokovic's strong win at Indian Wells 09 largely offsets these. In any case, Djokovic's 12-month score far exceeds Haas's.
Soderling over Tsonga. Ahead in both Calculations.
Djokovic over Soderling. Strongly ahead in both Calculations, including a 4-1 lead in head-to-head outcomes in the last two years.
del Potro, Roddick, Gonzalez, Cilic, Wawrinka.
In the expected match-ups among the players just named, the favorites lead by moderate amounts in all calculations of both kinds.
del Potro over Wawrinka.
Roddick over Gonzalez.
del Potro over Cilic.
del Potro over Roddick.
Nadal, Murray, Monfils, Stepanek, Ferrer.
The head-to-head record is thin for all but Nadal v. Murray.
Monfils over Ferrer.
Murray over Monfils.
Nadal over Stepanek.
Nadal over Murray. Rafa leads in the 12-month calculation by a moderate amount but more significantly in the head-to-head record, at W-L 5-2 over the last two years.
Federer over Djokovic. Perhaps surprisingly, Djokovic shows a slight margin over Federer in 12-month performance, reflecting that in our calculation Roger's results are somewhat reduced as predictors because of his greater age. Novak showed better success at Miami 09 and at Paris Indoors and other late-season events. His edge is extremely small -- 3.48 vs. 3.39, or differential of 0.09 in our calculation. Meanwhile the head-to-head record is also close, at W-L 4-4 each in 2008-2009, where Federer's head-to-head wins are more heavily weighted, at U.S. Open 09 and 08 and at Cincinnati 09. Djokovic's most significant win over Roger came in the final round of Australian Open 08. Roger's calibrated head-to-head edge is therefore 0.17, slightly outweighing Novak's 12-month superiority in our scheme. Federer to the Final.
Del Potro over Nadal. This is another split verdict. Nadal's 12-month performance is the higher -- 3.71 vs. 2.73, or 0.98 differential. But del Potro has won their last three meetings, all on hard courts in 2009. His calibrated head-to-head edge comes to 1.76, outweighing Rafa's 12-month differential. Del Potro to the Final.
Final: Federer over del Potro. Roger has the 12-month edge -- a moderate differential of 0.66, reflecting his excellence throughout 2009. But del Potro has won their last two head-to-head meetings, including at London 09 and in their U.S. Open five-setter. These are balanced, however, by Roger's straight-set victory at Australian Open 09, to which are added three other Federer wins. Federer's calibrated head-to-head margin of 1.60 thus reinforces his overall higher achievement.
Having rigidly followed the prescribed scheme, we establish Roger Federer as our predicted winner at Melbourne. If that happens, it will be Roger's fourth Australian crown, his 16th Slam overall.
WOMEN'S SINGLES -- THE ELDERS
Can it be that Serena and Venus are now in our senior group?
Remarkably, both sisters have reached Elder status still close to their professional best. The athleticism, power, and mental strengths of both seemed as strong as ever at the 2009 finale at Doha, where Serena at age 28 defeated Venus at 29 in their final-round show-down there. With four Australian Open crowns in her collection, Serena is the front-runner to add another at Melbourne, at odds 5-1. Venus, who departed early in Australia last year, was finalist at Wimbledon, then lost to Clijsters at U.S. Open to finish the year at #6, merits odds at Melbourne of 20-1.
Also prominent among the Elders is the Russian star Elena Dementieva, now 28, of the wistful serve. Behind her magnificent movement and stroking, tall Elena has finished in the top twenty every year starting at the age of 19 in 2000, usually in the first ten, but she has never captured a Slam. Her best showing at Australian Open came as a semi-finalist last year. She beat Serena in the final round at Sydney 10 and will be a dangerous problem for any opponent, at odds 25-1 for capturing the crown.
A few months ago the female Post-Primes, aged 25-27, would have seemed a relatively weak group. The leaders were Zvonareva, Bartoli, and Pennetta, all solid performers but none likely to challenge for a Slam championship. Slightly lower in the rankings were two others -- Amanda Stosur, 25, who had been a late riser in singles, and Nadia Petrova, who had a long record of competitiveness among the other Russkayas, often within or just outside the world's first ten. Currently, I place odds for each of the five at Melbourne at 75-1.
But the outlook for the Post-Prime group has been hugely improved by two superstars, both from Belgium, both returning from periods of retirement. Kim Clijsters, now 26, came back last summer and showed a blistering ground game backed by superb movement, achieving the seemingly impossible, capturing U.S. Open. Then Justine Henin, now 27, returned to action in January 2010, having departed in spring 2008 amid a difficult early-year spell. The past achievements of the slender star, summarized in her seven Slam crowns, defied the size and strength advantage of most of her opponents.
Amazingly, Clijsters and Henin both reached the final round in the tune-up at Brisbane, 8 January 2010. For Henin, it was her first tournament back, but her level of play proved as strong as ever. In early rounds she defeated Petrova and Ivanovic, and against Clijsters she recovered from one set down to attain two match points. Both stars sizzled in their performance, the heavy hitting and superior movement of both accentuated by the perfect evening conditions. Kim was the eventual winner, capturing their third-set tiebreaker.
Their dazzling Brisbane battle left no doubt that both Clijsters and Henin are ready to resume elite status. I make odds for Melbourne as follows: Clijsters, 5-1, Henin 6-1.
THE PRIME AGERS
Representing our prime-aged group, 22-24, are five stars, all from Serbia or Russia.
Back in 2007 two precocious Belgrade-born women, aged 20 and 22, completed the year ranked at #4 and #3, respectively. That the small nation of Serbia could produce such talents during years of turbulence was astonishing. The younger and seemingly more promising of the two, Ana Ivanovic, was tall at 6-1 and strong at 155 pounds, suited for power, while the older, Jelena Jankovic, was a superbly controlled mover, capable of excellence in either defending or attacking. In 2008 Ivanovic became champion at Garros, while Jankovic, finished the year ranked at #1. But both stars faltered thereafter. Intermittent injuries hindered Ana's play, and she fail to reach the quarters in any of the six Slams that followed her Garros triumph. Her 2009 year-end ranking dropped to #22. Jelena, too, slipped backward, to #8 last year, though she produced some strong results in the second half. We make odds for Ivanovic at 50-1, Jankovic 25-1.
The greater strength of the Prime Agers lies in three powerful Russian women. Dinara Safina, 23, is a potent server and stroker at height 6-0. Always temperamental, Dinara's mental fragility worsened once she reached the top. Just behind Dinara in the final 2009 rankings at #3 was Svetlana Kuznetsova, now 24. Svetlana was a top-tenner at 19 when she won U.S. Open, and she added her second Slam at Garros 09, beating Safina in the final. A highly athletic, hard-hitting veteran, experienced beyond her age, Svetlana combines experience, talent, and physical prowess. I make odds for Melbourne, Safina 20-1, Kuznetsova 20-1.
Siberia-born Maria Sharapova, now 22, seldom tempers in her serving and stroking. Trained to exploit her 6-2 height using ferocious hitting, she seeks the initiative with nearly every shot. She won her first Slam, at Wimbledon 04, at age 17, and since then added U.S. 06 and Australia 08. Shoulder trouble intervened two years ago, spoiling her serving and causing a nine-month absence ending in May 2009. Her return came with improved serving and a triumph at Pan Pacific 09. But her successes were too few thereafter for her to recapture her year-end top-ten ranking achieved every year 2004-2008. Maria's odds at Melbourne: 15-1.
Two European Under-21's penetrated the WTA top eight for 2009, and several others were reasonably close. Their potential for rise suggests that the women's game is headed for major overturn, though not quite yet.
The cream of the group as 2009 ended appeared to be Caroline Wozniacki, now 19, who finished the year at #4. Despite her little-girl appearance and manner, Caroline showed herself a determined fighter, inclined to play patiently but assuredly capable of striking offensively and sustaining attack with good direction and force. Her best showing came in reaching the final at U.S. Open 09, where she lost to Serena in split sets. But then Caroline lost more matches than she won for the rest of the year, and she lost to both Venus Williams and Sharapova at the Hong Kong exhibition in January. Odds: 30-1.
Four other Europeans, all aged 20, join Caroline in the world's top 24. Victoria Azarenka is an even stronger hitter, mercurial in temperament, #7 in the 2009 rank order. She made a strong run at the Sydney tune-up, but the run ended in a loss to Dementieva. Agnieszka Radwanska plays a controlled game, at #10. Yanina Wickmayer, whose recent suspension for drug-test non-availability has been lifted, showed well in late summer and fall, reaching the semis at U.S. Open. Tall at 6-0, her end-of-year rankings have risen impressively since 2007. She won the Auckland tune-up in early January, beating top-seeded Pennetta. (She won her first two matches in the qualifying tournament for the Open.) Sabine Lisicki, of the excellent serve, had some strong moments in 2009, triumphing on clay at Charleston and making a good run at Wimbledon 09. But shoulder trouble then spoiled what followed. Odds: Azarenka 25-1, Radwanska 75-1, Wickmayer 50-1, Lisicki 50-1.
Other teenagers are Sorana Cirstea, 19, from Romania, who scored wins over Wozniacki, Azarenka, and Radwanska last summer, and America's Melanie Oudin, 18, who made a good impression at Wimbledon and U.S. Open 09 at height just 5-6. I make both at 150-1.
Here's the breakdown showing the likelihood of each group's providing the tournament champion.
An incongruity is evident. Women players are generally thought to reach maturity earlier than males. But here, the Youths and Prime Agers stand weaker among the women than among the men in their chances to win at Melbourne.
Prime Agers, 20%
The long absences in 2009 of several of the top superstars rule out using our computer-based prediction scheme for the women. The odds quoted above and also the predictions shown below are based on subjective judgment.
S. Williams, Azarenka, Zvonareva, Stosur, Ivanovic.
Serena lost to Dementieva at the Sydney tune-up on the very day of the Open draw. But her history of raising her game during Slams cannot be overlooked. Serena should march to the quarter-finals and, if she has found her power game, successfully prevail over young Azarenka.
Wozniacki, V. Williams, A. Radwanska, Li, Hantuchova.
If close to her best, Venus should prevail. Wozniacki's poor results since U.S. Open raise doubt that she can reach a prospective meeting with the tall American.
Kuznetsova, Dementieva, Pennetta, Clijsters, Henin.
A dazzling second-round meeting between Dementieva and Henin is all but certain. Elena's power and mobility can be dangerous, but if Henin can summon her strong play seen over the years, Justine should survive. Then Clijsters and Kuznetsova should meet in round four, where Kim should prove clearly the stronger. A Henin-Clijsters meeting should decide the quarter, where Kim's narrow edge, seen at Brisbane, is the more likely though scarcely certain outcome. Kim Clijsters to the Final Four.
Safina, Jankovic, Bartoli, Sharapova.
The fearless hitting of Sharapova must prevail in the likely fourth-round match-up with Safina. Maria's path to the Final Four thereafter should be smooth.
Serena was the winner in her last four match-ups with Venus, all in 2009. If injury-free, Serena is clearly the more athletic and should succeed in their likely semi-final here.
The last meeting of Clijsters and Sharapova came at Australian Open 07. There, and in their two previous meetings, Maria won in straight sets. But since then Maria's injury difficulties have led to repeated ups and downs, while Kim's retirement seems only to have refreshed her talent and spirit. In my opinion, Clijsters has proven herself the better defender and the steadier attacker than Sharapova. The likely winner is Clijsters.
A final-round match-up of Serena and Kim seems fitting, recalling their semi-final at U.S. Open 09, when the last point went to Kim, though unplayed. Clijsters showed herself the superior player through most of the going on that date, and she should so the same again. I believe that the good-natured Clijsters, who lost to Henin in the final rounds of 2003 and 2004, will defeat Serena and thereby win her first Australian championship.
Computers can help you a lot:
Which players are cold, and who's hot?
But when you feel certain
And up comes the curtain,
You're wrong just as often as not.
-Ray Bowers, Arlington, Virginia
FOOTNOTE 1 -- AGE OF PEAK RESULTS
In the following equation, y is the expected improvement in a player's result at two Slams one year apart (e.g., Garros 07 vs. Garros 06), while x is the player's age midway between the two Slams.
y = -0.174x + 3.96
Note that the value of y (i.e., improvement) changes from positive to negative when x is 22.759 years. That is the age when players on average stop improving and start declining in their results.
The equation was calculated from empirical data of actual results of top players in all Slams, 2000-2008.
FOOTNOTE 2 -- PREDICTION CALCULATIONS
In our First Calculation here, player performances in events over the past 12 months are weighted according to how well each predictor event has predicted results at the last nine Australian Opens. Of the 24 predictor events used here for predicting Australian Open 2010, here are the ones heaviest weighted:
U.S. Open 09, 7.74%
The predictor events are the Slams, 1,000-Series, and 500-Series events of 2009, along with a 24th event -- the several tune-ups for Australia the week of 3-10 January 2010, treated here as a single event.
Wimbledon 09, 6.52%
Australian Open 09, 6.13%
Miami 09, 5.68%
Paris Indoors 09, 5.40%
London Year-End 09, 5.40%
Our Second Calculation measures past head-to-head results. Each past meeting between two players is assigned three values, which show closeness of score, recency, and commonality of surface, respectively:
The three simple decimals, just assigned, are then multiplied together, thereby obtaining a three-decimal-place score for each past head-to-head meeting. The scores from the several meetings are then summed into an overall score for the head-to-head record of that given pair of opponents.
- closeness of score:
margin of three sets = 0.4
margin of two sets = 0.3
margin of one set = 0.2
in current year = 0.3
in preceding year = 0.2
in any earlier year = 0
add for most recent meeting = add 0.1 to above value
- commonality of surfaces:
predictor and target are same event (different years) = 0.5
same surface (clay, grass, or hard) and same indoors or outdoors = 0.4
moderate difference (indoors vs. outdoors, or hard vs. grass) = 0.3
large difference (clay vs. nonclay) = 0.2
In an exercise prior to the tournament's main draw, I performed the First and Second Calculations for all possible head-to-head match-ups among the highest 12 players -- a total of 68 prospective match-ups. Here is a count of how well the two Calculations agreed with each other:
- Both Calculations pointed to the same probable winner = 47
- The two Calculations pointed to opposite probable winners = 21
Examining the data from the above exercise, I selected a calibration factor for integrating results of the two Calculations. After applying the calibration factor in the 21 cases where the two Calculations produced opposite predictions:
- the player ahead in the First (weighted 12-month) Calculation became the final predicted winner in 11 cases.
- the player ahead in the Second (head-to-head) Calculation became the final predicted winner in 10 cases.
The calibration value selected above is used in the actual prediction for Australian Open 2010, results shown in text.
Between The Lines Archives:
1995 - May 1998 | August 1998 - 2003 | 2004 - 2015
If you have not already signed up to receive our free e-mail
newsletter Tennis Server INTERACTIVE, you can sign up here.
You will receive notification each month of changes at the Tennis
Server and news of new columns posted on our site.
This column is copyrighted by Ray Bowers, all rights reserved.
Following interesting military and civilian careers, Ray became a regular
competitor in the senior divisions, reaching official rank of #1 in the 75
singles in the Mid-Atlantic Section for 2002. He was boys' tennis coach for four
years at Thomas Jefferson High School for Science and Technology, Virginia, where
the team three times reached the state Final Four. He was named Washington
Post All-Metropolitan Coach of the Year in 2003. He is now researching a history
of the early pro tennis wars, working mainly at U.S. Library of Congress. A
tentative chapter, which appeared on Tennis Server, won a second-place award
from U.S. Tennis Writers Association.
Questions and comments about these columns can be directed to Ray by using this form.