Women Tennis Update – Fed Cup Friday, February 8, 2013

Written by: Staff on 7th February 2013

Women Tennis Update - Fed Cup Friday, February 8, 2013

epa02818218 The shadow of Irina-Camelia Begu of Romania in action against Roberta Vinci of Italy is seen on the clay during the final match in the singles competition of the Poli-Farbe Budapest Grand Prix WTA tennis tournament, 10 July 2011, in Budapest, Hungary. EPA/TIBOR ILLYES HUNGARY OUT |

Fed Cup

Still no word of withdrawals.

What Month Was My Player Born In?

About three years ago, the author heard about the results of a study saying that there was a correlation between birth month and success in certain team sports — baseball and basketball, if the author recalls correctly. (This was a radio program, so it wasn’t possible to take detailed notes.)

This is sometimes linked with something called the “Gauquelin effect,” or the “Mars effect,” which is extremely dubious scientifically — it claims links with planetary positions, and in at least some of the cases cited, it has been shown that Gauqelin’s data did not demonstrate correlation.

However, the radio claim was not based on the “Gauquelin effect,” which was announced, and largely debunked, more than half a century ago. The explanation given for the neo-Gaquelin results was that sign-ups for various youth sports teams were based on ages, and players who were just a little older or younger would have significant advantages — they would get more playing time, or be the strongest on the team, or something. So let’s play with the idea anyway. Is there a tennis advantage?

We first looked at this at the end of 2009, and there was a curiosity: There were relatively few players born in November and December, and few top players born in January. We looked at it again in early 2011, and 2012, and the results were somewhat similar. We now have a new Top Hundred. Has anything changed?

We must be cautious. We’re going to look at the birth months of the WTA Top Hundred (based on the rankings at the start of the Australian Open). Now suppose we were to find that (say) players born in September, October, and November were twice as common as those born in any other three-month period. Does this mean that being born in those months implies an advantage?

Not necessarily. It might be coincidence. Not likely with a ratio like that, but certainly not impossible.

It might have to do with the parents. The single best way to have kids who are great athletes, according to another, better study, is to have great athletes as parents. But consider this: In the case of outdoor tennis, the primary “down season” is the North American winter — roughly December, January, and February. Parents who themselves played tennis, and preferred to play outdoors, might play less in the winter months — and so, since they need, ahem, other recreational activities, might be more likely to conceive children in those months, and so have the children born in September, October, and November.

Or, of course, there could be an effect of the schedule of outdoor tennis clinics. Or… well, or almost anything. While we know what the results were for past years, we are deliberately writing this preface before we even know what the results of this will be for 2013, so we won’t produce speculations influenced by the data. Our next step, of course, is to take the WTA Top Hundred and determine their birth month balance.

January (total of 12): Kerber (5), Kirilenko (15), Hsieh (27), Peng (32), Cornet (41), Flipkens (43), Robson (53), Martic (62), Hampton (63), Parmentier (67), Hercog (79), Chang (86)

February (total of 11): Li (6), Vinci (16), Safarova (17), Jankovic (21), Zakopalova (22), Arvidsson (39), Tatishvili (54), Cetkovska (57), Pennetta (59), Beck (71), King (76)

March (total of 12): A. Radwanska (4), Kvitova (8), Stosur (9), Stephens (25), Dominguez Lino (46), Oprandi (61), Scheepers (65), Erakovic (68), Morita (72), Arruabarrena-Vecino (77), Voegele (89), Panova (93)

April (total of 6): Sharapova (2), Errani (7), Cirstea (29), Hantuchova (44), Johansson (88), Doi (92)

May (total of 12): Cibulkova (14), Lepchenko (20), McHale (35), Watson (50), Hradecka (51), Babos (73), Pervak (82), Tsurenko (85), Peer (90), Cadantu (91), Torro-Flor (96), Mladenovic (98)

June (total of 7): Petrova (12), Makarova (19), V. Williams (26), Kanepi (34), Schiavone (48), Kuznetsova (75), Bratchikova (87)

July (total of 6): Azarenka (1), Wozniacki (10), Pavlyuchenkova (23), Barthel (38), Zheng (40), Medina Garrigues (52)

August (total of 5): Vesnina (47), Begu (55), Govortsova (58), Hlavackova (66), Larsson (69)

September (total of 12): S. Williams (3), Shvedova (28), Suarez Navarro (33), Lisicki (36), Pironkova (37), Wozniak (42), Halep (45), Niculescu (49), Oudin (84), Daniilidou (94), Zvonareva (95), Date-Krumm (100)

October (total of 5): Bartoli (11), Wickmayer (24), Rybarikova (64), Davis (81), Czink (97)

November (total of 4): Ivanovic (13), Goerges (18), Minella (78), Soler-Espinosa (83)

December (total of 8): Paszek (30), U. Radwanska (31), Jovanovski (56), Bertens (60), Rus (70), Giorgi (74), Voskoboeva (80), Vandeweghe (99)

If players were born at random, we would expect to have 8 or 9 players born each month, and 25 in each three month period. Instead, we have 35 born in January-March, 25 born in April-June, 23 born in July-September, and just 17 in October-December.

This compares to the early 2011 figures of 29 born in January-March, 29 in April-June, 25 in July-September, and just 17 in October-December. In early 2012, the figures were 31 in January-March, 24 in April-June, 26 in July-September, and 18 in October-December. In other words, we have a pretty consistent bulge in the first three months, and an even more noticeable trough during the last three.

It’s a small sample, and no way to expand it except to keep gathering the data for several more years. It might be coincidence. But the pattern keeps repeating — and over a long enough period that there has been some turnover in the Top Hundred. Is there an explanation? If you can figure out what it is, maybe you can be the one giving the radio lectures….

Topics: Australian Open, Fed Cup, Sports, Tennis, Tennis News, Wta