Paul Erdős (1913-1996)
The eccentric Hungarian mathematician Paul Erdős (1913-1996) was one of the most prolific publishers of papers in mathematical history (apparently second only to Leonhard Euler). Erdős wrote around 1,500 mathematical articles in his lifetime, with 511 direct collaborators.
The Erdős number describes the "collaborative distance" between an individual and Paul Erdős, as measured by authorship of mathematical papers. Paul Erdős is the only person having an Erdős number of zero. The lowest Erdős number of a coauthor is 1.
Diagramatic explanation of Erdős number [by user:h2g2bob, Wikipedia ]
Other similar number ratings include:
- Bacon number - as in the game Six Degrees of Kevin Bacon. [link]
- h-index - index quantifying both the actual scientific productivity & apparent scientific impact of a scientist. [link]
- Kibo number - someone who has received e-mail from Kibo either directly or through shared contacts.
- Shusaku number - "distance" between a Go player & Honinbo Shusaku, measured in Go opponents. [link]
- Small world experiment - comprised several experiments conducted by Stanley Milgram examining the average path length for social networks of people in the USA. [link]
- Stringfield number - application of the same idea to the field of ufology - connecting ufologists with the late Leonard H. Stringfield.
- Stands for World Uncontested Chess Champions (15 currently).
- It is similar to the Shusaku number in that it measures the distance between a chess player and each of the 15 Uncontested World Chess Champions.
- The Uncontested World Chess Champions are - Wilhelm Steinitz - Emanuel Lasker - José Raúl Capablanca - Alexander Alekhine - Max Euwe - Mikhail Botvinnik - Vasily Smyslov - Mikhail Tal - Tigran Petrosian - Boris Spassky - Robert J. Fischer - Anatoly Karpov - Garry Kasparov - Vladimir Kramnik - Viswanathan Anand
- If there is no direct connection found then a score of 6 is allocated to the chess player (for that World Chess Champion interaction).
- Each World Chess Champion has a score of zero for their own interaction.
- The numbers obtained from the interactions between the chess player and each World Chess Champion are added together to give a WUCC15 number.