Forum for Science, Industry and Business

Search our Site:

Statistic Phenomenon on the Pitch: Often Two Players with the Same Birthday at the World Cup

12.06.2008
The German defender Philipp Lahm and the Portuguese midfield star Maniche were both born on 11. November – and they were both playing in the game for the third place at the World Cup 2006.

Anyway, in more than half of the games at the World Cup 2006 at least two persons on the field had the same birthday. That is what Yanina Lyesnyak found out within the scope of her bachelor thesis supervised by Prof. Walter Krämer.

And for the European Championship 2008 which has just started, the graduate of the study program “data analysis and data management” prognosticates a similar result. The reason is the so-called birthday paradox.

It implies that the probability to find two persons with the same birthday within a group of 23 people chosen at random amounts to more than 50 percent. Yanina Lyesnyak discovered her interest in this phenomenon rather accidentally: “Two friends of mine are both called Katharina and share the same birthday – I always thought this to be fascinating”, explains the graduate. During her study she started to deal with this topic and wanted it to become the subject of her final thesis. Then she only needed an object of investigation. “I looked for something that involves 23 people to examine the birthday paradox. A soccer game already involves 22 players – and I just added the referee”, she reports.

And then she examined all 64 games of the Soccer World Cup 2006 in view of the birthday paradox. The result: in 53 percent of the games there were actually at least two people on the field who shared the same birthday. Sometimes even three; for example, in the game Argentina versus Serbia-Montenegro. And the game Netherlands versus Argentina was especially striking as there were three pairs with the same birthdays. In her analysis Yanina Lyesnyak just dealt with the initial team line-ups, the players taken off were not considered. “But the result would have been the same as the number of people being together at random would again be 23”, she explains.

To further substantiate her results, she also examined the Women’s Soccer World Cup 2007; and here the paradox was validated again. “To get an almost 100 percent hit rate one has to examine 66 persons. With 66 persons, picked at random, the probability that two of them share the same birthday is nearly 100 percent”, says Lyesnyak. She regards the season pattern of births as the reason for this phenomenon.

“Most of the children are born at the end of summer or at the beginning of spring. An the fewest in December and February”. This can at least be applied to Europe – and with 14 teams most of the teams at the World Cup came from Europe. It therefore has to be seen whether the birthday paradox will appear during more than 53 percent of all games of the European Championship in Austria and Switzerland.

Ole Luennemann | alfa
Further information:
http://www.tu-dortmund.de

More articles from Statistics:

New drug reduces transplant and mortality rates significantly in patients with hepatitis C
29.05.2017 | Intermountain Medical Center

Institutions of higher education spent more than Euro 48 billion in 2014
19.05.2016 | Statistisches Bundesamt

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige