Twelve months ago Wimbledon 2012 began amid dampness and chill. Eliminated early were favorites Nadal, Berdych, and top-seeded Sharapova. Probably few sensed what was ahead in the second week -- with the sunshine came a magnificent blend of baseline power and aggressive net attacking that marked the battles among the surviving titans. Triumphant at the finish were Roger Federer, who defeated Novak Djokovic and Andy Murray in sizzling split-setters, and Serena Williams, whose newest victory came after two years of intermittent injury and sickness.
 
For Serena the twelve months following last year's classic have been golden. There were more medical problems -- toe, ankle, back, viral illness. But Serena would nearly sweep the women's calendar, in turn capturing the Olympics, U.S. Open, Istanbul at year's end 2012, then Miami, Madrid, the Italian, and Roland Garros in 2013.
 
Meanwhile the men's tour produced three unofficial regime changes. Taking command in July 2012 was Andy Murray, who won Olympics on freshly sown grass at Wimbledon and then won U.S. Open. Next to rule was Novak Djokovic, who captured the 2012 year-ender in London and Australian Open 2013. Finally Rafael Nadal, who returned from absence in the second half of 2012 caused by knee trouble, won Indian Wells and dominated the 2013 clay circuit, winning Garros. Meanwhile Roger Federer's greatness was sometimes seen, but his dominance seemed past.
 
But although much has transpired, the picture entering Wimbledon 2013 looks a lot like it did one year ago. The members of the long-standing Big Four -- Murray, Djokovic, Nadal, and Federer -- seem likely to provide the 2013 champion, even as the group just behind, also unchanged from last year, provide serious threats in any head-to-head meeting with one of the giants. Matters seem largely unchanged also among the women. Last year's top two seeds -- Sharapova and Azarenka --- offer the only likely threats to Serena Williams if La Prima is close to her best. Both Maria and Vika join Serena as the women's Big Three.
 
The skidding and irregular bounce on the grass at Wimbledon continues to benefit the server over the serve-returner, the attacker over the defender, the net attacker over the baseliner. Although these effects are less pronounced than they were decades ago, they are consistently seen in data taken from the late rounds of Slams over the last seven years. An especially indicative measure comparing the Slams is aces per point:
 
Aces per total points played
 
Wimbledon, 10.13%
Australian Open, 7.68%
U.S. Open, 6.64%
Garros, 5.55%
 
In truth, most of today's players are most comfortable in back court whatever the surface, and at Wimbledon there will be many matches where sustained baseline exchanges are almost as prevalent as elsewhere. But when two superstars face off across the net, underlying the tactics and indeed the outcomes will be each opponent's willingness and ability to operate from on or nearly on the baseline, avoiding deep court, and to move forward in making forcing strikes and in following them to forecourt. A key will lie in the forcefulness of the first serves and the returns of second serves, either opening the way for first-strike tactics.
 
THE INDICATORS
 
Our analysis starts with three indicators, paralleling those used in our recent Garros predictions.
 
-- Basic Indicator. Player results from the last two years are weighted according to how well results at the various tournaments have correlated historically with results at succeeding Wimbledons.
 
-- Quality-Win Quotient, QWQ. Match wins over top-level opponents in 2013 are compared with total of all losses.
 
-- Grass-Court Index, GCX. Each player's grass-court ability is measured by averaging three sub-indicators: (1) career grass-court matches won minus lost, (2) past success at Wimbledon, aged over the last ten years, and (3) data showing serving ability.
 
The Men -- Basic Indicator
 
1. Novak Djokovic, 24.8
2. Andy Murray, 16.3
3. Rafael Nadal, 14.4
4. Roger Federer, 12.9
5. Juan Martin del Potro, 6.6
 
Our leader here is Novak Djokovic, whose wonderful flexibility, body control, and fleetness in court movement make him a foremost performer on all surfaces. Novak is at his best in extended, violent corner-to-corner rallies at baseline, and he is also superb in responding to an opponent's forcing play, answering often with brilliant defensive-to-offensive ripostes. These strengths translate well into modern grass-court tactics, where Novak's opponents, finding themselves inferior to Novak from back court or uncomfortable with the fast and unpredictable bounces on grass, become inclined to come forward injudiciously, thus playing into Novak's strengths. Novak is also talented in cat-and-mouse play following drop shots. Finally, Novak's recent performance at Garros, where he nearly defeated Nadal, suggests that in his cycle of ups and downs, Novak is currently on upswing.
 
Quality-Win Quotient, QWQ
 
1. Rafael Nadal, 66.0
2. Novak Djokovic, 13.8
3. Andy Murray, 7.5
4. Stan Wawrinka, 3.0
5. Tomas Berdych, 2.6
 
Rafael Nadal is the greatest clay-court player of all time, and most of his achievements in 2013 have come on clay. But he won Indian Wells, his only nonclay event of 2013 to date.
 
Rafa's grass-court abilities are excellent, he having reached the Wimbledon final round five times in the last seven years and won the top prize in 2008 and 2010. His first serve has become a strong weapon on grass, its left-handed spin adding to its effectiveness, and his second serve, which is relatively weak on other surfaces, profits from the grass-court skid. He is excellent at net and is devastating overhead. His strong body helps control his movement on the slippery surface, and his weight adds footprint pressure. His extreme topspin in stroking is less influential on grass than on other surfaces but remains problematic for opponents. The soft surface should avert Rafa's concerns for the wear-and-tear of harder courts on his body and troublesome knee.
 
Nadal's extreme lead shown here over Djokovic and the others may exaggerate Rafa's superiority. In the period of this measurement, 2013 to date, he achieved 16 match wins over top opponents (13 on clay), against a total of only 2 losses. Meanwhile Djokovic's elite wins totaled 8, against 3 total losses.
 
Grass-Court Index, GCX
 
1. Roger Federer, 19.1
2. Lleyton Hewitt, 9.0
3. Rafael Nadal, 9.0
4. Andy Murray, 8.6
5. Novak Djokovic, 6.8
 
Roger Federer's balanced perfection in all aspects of tennis explains his amazing success at Wimbledon, where his total of seven singles crowns equals Pete Sampras's total. No other player has more. In his first Wimby triumph, in 2003, Roger brilliantly showed that the net could still be a winning place in an era dominated by the back-court skills of most other pros. But during the years of Roger's greatness that followed, despite his unmatched skills at net Roger rarely employed an all-out net-attacking style. Typically he chose whatever tactics seemed right for the particular opponent, the conditions, and his sense of his own strengths. He usually was able to prevail from back court, where the stresses were easier on body and joints. But the rise of Nadal and other strong challengers required Roger more often to be the attacker, forcing his way forward early in points. Roger's attacking forehand carried so much overspin that it often seemed to dive wickedly downward late in its flight to intercept a line, often setting up Roger's coup at net.
 
At Wimbledon, Roger's serving ability will be important, winning quick points and establishing early opportunities to attack. He is very good in attacking the opponent's serve at critical times and he can be superb in extended exchanges from back court. But to win very long matches against the superb movers and strikers that he will meet in the late rounds at Wimbledon -- opponents five years or more younger than Roger -- Roger cannot allow too many tiring exchanges. He must be the consistent aggressor, at least in the must-win sets.
 
The fourth member of the Big Four, Andy Murray, ranks second or third in the first two indicators and shows a score here almost as good. Largely accounting for his scores were his superb summer 2012 run and his second-place finish at Australian Open 2013 along with his triumphs at Miami and Queen's 2013. Andy's weaponry in power, variety, and court coverage is as potent as those of the other elites, perhaps even more so. But will he resolve to employ his assets aggressively? Will he operate from close-on baseline, not in deep court, ready to move forward to deliver forcing blows to the sides and corners or perhaps attack with low and short angles? These tactics seemed to explain his 2012 run. They were also detectable in Andy's wins over Tsonga and Cilic in his recent conquest at Queen's 2013. Like Federer, Andy is highly competent in patient rallies of neutrality, but too much patience, indeed too much defense however brilliant, will not win this Slam crown for Andy.
 
Second place in this indicator belongs to veteran Lleyton Hewitt, now 32, Wimbledon champion in 2002. His high score here mainly derives from his outstanding W-L record of 116-34 on grass over his full career. Only Federer's, at 121-17, is better. Lleyton proved that he is still a strong grass performer last week at Queen's where, unseeded, he defeated Dimitrov, Querrey, and del Potro enroute to a semi-final meeting with Cilic, which he lost in split sets.
 
Composite of three indicators
 
Each of our three indicators, above, points to a different likely champion. Here is our composite, reached by averaging.
 
1. Rafael Nadal, 30.8
2. Novak Djokovic, 15.7
3. Roger Federer, 13.5
4. Andy Murray, 11.8
 
The Big Four are conspicuously ahead of all others. What of the others of the next group? After Hewitt, fifth, are three members of the generally acknowledged Second Four, strong performers all, any of them capable of temporarily penetrating the top group. Two are relentless hammerers -- Tomas Berdych and Juan Martin del Potro, alike powerful servers and strikers. Jo-Wilfried Tsonga also commands heavy and steady power and adds high athletic mobility, variety, and willingness to attack boldly. Completing our first ten are extreme servers Isner and Raonic.
 
5. Lleyton Hewitt, 4.1
6. Jo-Wilfried Tsonga, 3.9
7. Tomas Berdych, 3.5
8. Martin del Potro, 2.8
9. John Isner, 2.2
10. Milos Raonic, 2.1
 
Just outside is David Ferrer, eleventh, who brings a balanced game capable of strong attack, defense, and counter-attack along with moderate power, which place him sixth in Basic Indicator but considerable lower in the others.
 
What of prospective newcomers? Several members of our watch lists of the last twelve months have risen impressively during their periods of list tenure. None seem yet ready to win a Slam crown, but an upward break-out to reach late or middle rounds at Wimbledon or a strong effort against a favorite seem possible for these listees: Jerzy Janowicz, Benot Paire, Grigor Dimitrov, Roberto Bautista Agut, Frederico Delbonis.
 
PREDICTIONS (MEN)
 
The seedings were reached under rules previously agreed by players and tournament, but the product was scarcely satisfying. Rafael Nadal, recent champion at Garros and a two-time Wimbledon champion, was seeded #5 -- i.e., outside the top four. Thus it was left to the luck of today's draw to avoid a prematurely early meeting between Rafa and one of the other members of the long-standing Big Four.
 
The draw failed to provide this solution. Rafa is drawn prospectively against Federer in the quarter-finals, the survivor then to face Andy Murray in the semis. Hewitt is also in that same quarter. The draw thus strongly favors Djokovic among the Big Four and strongly disfavors Nadal and Federer.
 
Our predictions, next, rely on our indicators along with past head-to-head results, though ultimately on judgment.
 
Top Quarter
 
First-seeded Djokovic has a comfortable path to the fourth round, where his opponent would be Tommy Haas, who split two matches with Novak this spring. If Haas stumbles earlier, then Feliciano Lopez would bring strong grass-court credentials in facing Novak, including tenth place in our Grass-Court Index, GCX. But Novak has won all five of their past meetings, all on non-grass surfaces. Thus, Novak should reach the quarter-finals safely albeit moderately well tested, probably by Haas, in the fourth round.
 
Also reaching the quarter's final will be either Richard Gasquet or Tomas Berdych. Berdych is favored in all three of our indicators, but Gasquet has the head-to-head edge, having won five of their eight past meetings (none on grass). Gasquet seemed on the upswing during the spring and went farther than Berdych both at Garros this year and at Wimbledon last year. Here, we break from our indicators and choose Gasquet to become Djokovic's quarter-final opponent.
 
But Djokovic after several tournament matches should have found his best tennis and, having beaten Richard in their last five meetings without losing a set, all on non-grass, should advance confidently into the tournament's Final Four. Djokovic over Gasquet.
 
Second Quarter
 
David Ferrer is the high-seed in this quarter. He narrowly trails Milos Raonic in our Composite of Indicators, but holds a 4-0 W-L record against the tall Canadian, who is David's likely fourth-round victim. Next for David would come Juan Martin del Potro, who is highest in the Composite among those in the lower half of this quarter. Juan Martin also leads David in the Composite but has lost to David in their last four meetings. David has also won their two matches on grass, including at Wimbledon 2012, both in straight sets. Ferrer over del Potro.
 
Third Quarter
 
Rafael Nadal and Roger Federer each stand so far ahead of all others in this quarter that a deciding meeting of the two seems assured. Blocking the way are two superior servers, John Isner and Jerzy Janowicz, either of whom if at their very best could make things interesting. Besides Isner, also in Nadal's half of the quarter are Lleyton Hewitt, who has lost his last thirteen sets against Rafa, and Stan Wawrinka, who has never beaten Rafa in ten tries.
 
Nadal and Federer have played each other three times on grass, each time in a final round at Wimbledon. Roger won in four sets in 2006 and in five in 2007. Rafa won in five in 2008. Since that last affair, Rafa has won eight of their twelve meetings, including two in 2013. Thus the message of the head-to-heads reinforces the message of our Indicator Composite. Nadal over Federer.
 
Fourth Quarter
 
Only Andy Murray and Jo-Wilfried Tsonga are in the top ten of our Composite, and both should reach the final of this quarter, though both must pass interesting tests along the way. Andy is bracketed to face Mikhail Youzhny, who defeated Nishikori, Kohlschreiber, and Gasquet enroute and then won the first set against Federer in grass in the final at Halle last week. Andy was the winner in both his past meetings with Youzhny and leads in all our indicators. Meanwhile Tsonga is three years younger than his main obstacle, Benneteau, and has won four of their last five meetings including at Wimbledon 2010.
 
Murray and Tsonga should provide a brilliant quarter-final. To be expected are violent serving by both, determined aggression by Jo-Wilfried, and potent counter-blows by Andy. That was the pattern seen in their meeting last week at Queen's, won by Andy as Jo-Wilfried's strong attacking faded after Jo-Wilfried won the first set. Andy, who leads in all our indicators, has also won their last seven meetings including four on grass. Murray over Tsonga.
 
Semis and Final
 
Far ahead in all our indicators and in head-to-head play, Novak Djokovic should win comfortably over David Ferrer even if Novak is slightly off form.
 
But there is far less certainty in other semi-final, pitting Rafael Nadal and Andy Murray. Murray leads in Basic Indicator, Nadal in QWQ and GCX, but Rafa's margin is so large in QWQ that the Composite is strongly tilted to favor Rafa. The head-to-head history shows Rafa ahead in W/L, 13-5 careerwise, but Andy has won their last two meetings, both on hard courts. Rafa has won all three match-ups on grass, all at Wimbledon, Rafa losing only one set in those affairs. Rafa has not played since capturing Garros less than three weeks ago; Andy triumphed at Queen's.
 
It should be a magnificent show, probably won by the warrior who attacks most effectively in the kind of first-strike tennis sketched at the start here. If one man is kept on the defensive considerably more than the other, the defensive player can expect to lose the match. Nadal over Murray.
 
Novak Djokovic should arrive at Centre Court well tuned to the grass and the playing conditions, free of fatigue after a comparatively easy path to the final. Rafael Nadal will have been through several severe tests, probably one or two of them extended in duration. The edge in mental and physical freshness should thus belong to Novak. Novak has the higher official world ranking, at #1.
 
Ever since his near-victory over Rafa at Garros, Novak has been the betting favorite to win Wimbledon.
 
But our indicators do not agree. Novak leads in Basic Indicator, in part attributable to Rafa's long absence in late 2012. But Rafa leads strongly in QWQ, less strongly in GCX, and thus fairly strongly in Composite. The question rises: whether Rafa's large numerical edge in QWQ expresses accurately his superiority.
 
What of their past head-to-head history? Nadal has the edge in career W/L results, 20-15. The two divided their two matches in 2013, both on clay. On grass, Nadal won at Wimbledon 2007 and Queen's in 2008, Novak won at Wimbledon 2011. Thus the verdict is inconclusive.
 
Both men are masters of tennis in all areas. Both are absolutely supreme in back court, in forceful rallying, in serve-returning, in close-in exchanges, in movement. Rafa has the heavier overspin in stroking, Novak the stronger second serve. Either could win. Believing that it will be Rafa who is better able to attack, albeit selectively, I choose the message of our indicators. Nadal over Djokovic.
 
It will be Rafa's third Wimbledon conquest, his thirteenth Slam.
 
INDICATORS -- THE WOMEN
 
Basic Indicator
 
1. Maria Sharapova, 18.9
2. Serena Williams, 17.5
3. Victoria Azarenka, 15.8
 
Quality-Win Quotient, QWQ
 
1. Serena Williams, 50.9
2. Victoria Azarenka, 16.8
3. Maria Sharapova, 16.2
 
Grass-Court Index, GCX
 
1. Serena Williams, 25.8
2. Petra Kvitova, 9.2
3. Sabine Lisicki, 8.9
 
Composite of three indicators
 
1. Serena Williams, 31.40
2. Maria Sharapova, 14.6
3. Victoria Azarenka, 11.5
 
The women's Big Three dominate in our indicators comparably to the Big Four men. Maria Sharapova leads in Basic Indicator, helped by Serena's inactivity in late 2011 and early 2012. But Serena leads in QWQ, GCX, and in our Composite.
 
Serena's greatness starts with her first serve, delivered with extreme power and control from a technique that is worthy of copying by all. Serena is ahead of all others in total aces in 2013 and in first-serve points-won percentage. Note that unlike among the male pros, only a few females show more aces than double-faults -- not Sharapova, Azarenka, nor Kvitova during 2013 to date, for example. Far ahead in this measurement is Serena, the only pro with more than twice as many aces as double-faults.
 
Serena also brings the most powerful ground strokes in women's tennis, along with extreme court mobility and athleticism that together often enable her to reverse point-dominance by an opponent. On occasions, however, she slips into a kind of torpor, probably from a momentary loss of confidence in her big game, bringing spells of error-making and negative court manner. But when in serious trouble late in big matches, she usually overcomes her sluggishness and, having found her best game, manages to renew her energy and confidence, prevailing at the finish.
 
Sharapova, second in our Composite, brings serving and stroking velocities comparable to Serena's along with very good court movement and counter-punching ability. But there is risk in Maria's all-out striking, meaning that an opponent able to withstand Maria's heavy bombardment can hope to outlast her in rallies. It would be interesting to see Maria, who has excellent skills in nearly all areas, play slightly more patiently, especially against her strongest opponents, diverting more of her effort into creating greater topspin in both serving and stroking.
 
Victoria Azarenka has a firm, well-balanced game that is generally strong enough to defeat all but the first two. Vika is well behind Serena and Maria in first-serve winning percentage but well ahead in second-serve winning percentage, a condition indicating an edge for Vika once points become neutralized, as in extended rallies.
 
The Second Three in our Composite are an unexpected trio. Kvitova and Lisicki are both strong in GCX, Kvitova having won Wimbledon 2011 and Lisicki showing well in our serving data. Radwanska is strong only in Basic Indicator.
 
4. Petra Kvitova, 7.3
5. Agnieszka Radwanska, 5.8
6. Sabine Lisicki, 3.2
 
From our still-active watch lists of the last twelve months, increasingly threatening to the leaders have been Sara Errani, Sloane Stephens, Laura Robson, Kristina Mladenovic, Madison Keys, Donna Vekic, and Garbine Muguruza. None of them seem yet ready to capture Wimbledon but any of them could create major stir.
 
THE PREDICTIONS -- THE WOMEN
 
Top Quarter
 
The draw favored Serena by separating her from both Sharapova and Azarenka until the final round. There is no serious threat in Serena's quarter, though Lisicki has the serving and stroking power to compete for dominance when Lisicki is serving. Kirilenko and Kerber are fine players but lack Serena's power and athleticism. (Kirilenko leads Kerber strongly in GCX .) Serena over Kirilenko.
 
Second Quarter
 
Agnieszka Radwanska leads Li Na in our indicators, showing a surprisingly strong score in GCX. She also has the stronger recent results. Agnieszka over Li
 
Third Quarter
 
Though neither is strong in QWQ, Caroline Wozniacki has the edge over Sara Errani in GCX and in our Composite of Indicators. But in the quarter's final, Caroline will be badly outmatched by the power striking of Maria. Sharapova over Wozniacki.
 
Bottom Quarter
 
Petra Kvitova won Wimbledon in 2011 behind a vicious left-handed serve, typically sliced wide. Petra's magic lifted her close to the world #1 ranking, but her results then slipped amid spells of error-making. Her serve, too, has been disappointing, as she shows a total of 124 aces against 187 double-faults for the current year to date. She competed at Eastbourne last week winning once before losing closely to Wickmayer.
 
Meanwhile Victoria Azarenka has again been plagued by various afflictions that require withdrawals. Otherwise, since winning Australian Open and Doha 2013 she has regularly reached late rounds of events, including the semis at Garros 2013. She stands ahead of Kvitova in our Composite although well behind in GCX. Kvitova has the head-to-head edge owing to two victories at Wimbledon, in 2010 and 2011. The margin here is close, but the edge in the Composite rules. Azarenka over Kvitova.
 
Semis and final
 
By any measure, Serena stands to defeat Agnieszka in their semi-final.
 
Sharapova is less strongly favored over Azarenka in a match-up that repeats the semis at Garros 2013. Maria won that affair, displaying her superior thunder but also her sometimes troublesome double-faulting. After losing the first set, Vika began blunting Maria's blows and began answering in kind. But the match was always Maria's to win or lose, and she closed out the third set with her best serving.
 
Maria, with a clear margin in Basic Indicator and GCX, leads Vika in our Composite. The two are roughly even in head-to-head results. Maria should repeat her Garros win, probably with a stronger margin. Sharapova over Azarenka.
 
What will have changed since Serena Williams's decisive win over Sharapova at Garros? Only that the scene will be a place where Serena has captured the crown in three of the last four years. (Maria triumphed there in 2004, Serena twice in the two years just before that.) Serena, who is now at the peak of her powers and well ahead of Maria in all our indicators except Basic, should produce her best. Serena over Sharapova.
 
It will be Serena's sixth Wimbledon crown, her seventeenth Slam in all.
 
Thus the recent winners at Roland Garros will become the Wimbledon champions of 2013. Rafael Nadal and Serena Williams will remain our current Il Primo and La Prima of pro tennis.
 
--Ray Bowers, Arlington, Virginia
 
APPENDIX -- MORE ON THE INDICATORS
 
The following paragraphs apply to the men's calculation. The women's calculation parallels the men's but has some differences in detail. In all indicators among both men and women, the values shown are the raw scores normalized by subtracting the value of the 17th-highest score and then apportioning the top sixteen scores to reach a total of 100.
 
Basic Indicator rests on eleven years of data showing how well results at various predictor events have correlated with results at succeeding Wimbledons. These correlations produce the weights used here in computing each player's Basic Indicator from his results at 34 predictor events. Of these predictors, the heaviest weighted here are Wimbledon 2012, Australian Open 2013, Indian Wells 2013, U.S. Open 2012 (in that order). The earliest of the predictor events is Queen's/Halle 2011 and the most recent is Queen's/Halle 2013.
 
Quality-Win Quotient, QWQ, weights "quality wins" in 2013 over fourteen high-level opponents. (These are Djokovic, Nadal, Federer, A. Murray, Tsonga, Berdych, del Potro, Ferrer, Gasquet, Cilic, Tipsarevic, Wawrinka, Raonic, and Almagro.) Wins over a member of the Big Four count triple, those over the Second Four count double, and those over the next six count singly. The player's resulting tally is then divided by his total of losses to all opponents in the period, thus reaching ratio QWQ.
 
Grass-Court Index, GCX. Three sub-indicators are combined to reach GCX. The first sub-indicator is each player's career total of grass-court wins minus one-half of grass-court losses. (The reduced weighting of losses here reflects the view that losses on this atypical surface to some degree contribute to a player's likelihood of future success on grass.) The second sub-indicator is success at past Wimbledons, where weighting strongly favors recency. The third sub-indicator measures serving prowess and reliance, here seen to be more important on grass than on other surfaces. This sub-indicator combines two subordinate sub-indicators, both taken from available 2013 data on all surfaces. The first compares first-serve winning percentage vs. second-serve winning percentage; the second is plurality of aces over double-faults per games served.
 
The Indicators at Garros 2013
 
How well did our indicators predict the actual results at Garros 2013?
 
To answer, we ascertain how well each indicator correctly foretold the tournament's actual final-eight members, final-four members, runner-up, and champion, respectively, a total of 15 possible credits. One extra credit is given for correctly predicting the champion. If all these are correctly predicted, that indicator's success is 100%. If all are correctly predicted except for one member of the final eight, the score would be 94%.
 
Here are the success scores from Garros 2013 --
 
Men's Singles
 
Basic Indicator, 50%
Quality-Win Quotient, QWQ, 69%
Clay-Court Index, CCX, 62%
Composite of above three indicators, 69%
Final prediction including head-to-head results, 75%
Benchmark, tournament seedings, 50%
 
Women's Singles
 
Basic Indicator, 75%
Quality-Win Quotient, QWQ, 69%
Clay-Court Index, CCX, 62%
Composite of above three indicators, 81%
Final prediction including head-to-head results, 81%
Benchmark, tournament seedings, 75%
 
All the women's predictors except Basic Indicator correctly placed Serena Williams first, and three of them (Basic Indicator, Composite, and Final prediction) correctly predicted all members of the actual final four.