Six degrees of separation

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Six degrees of separation refers to the idea that, if a person is one "step" away from each person he or she knows and two "steps" away from each person who is known by one of the people he or she knows, then everyone is no more than six "steps" away from each person on Earth. Several studies, such as Milgram's small world experiment have been conducted to empirically measure this connectedness. While the exact number of links between people differs depending on the population measured, it is generally found to be relatively small. Hence, six degrees of separation is somewhat synonymous with the idea of the "small world" phenomenon.

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[edit] Early conceptions of the six degrees idea

[edit] The "shrinking world" of Frigyes Karinthy

In 1929, a Hungarian author named Frigyes Karinthy published a volume of short stories titled "Everything is Different." One of these pieces was titled "Chains," or "Chain-Links." The story investigated in abstract, conceptual, and fictional terms many of the problems that would captivate future generations of mathematicians, sociologists, and physicists within the field of network theory [1]. In particular, Karinthy believed that the modern world was shrinking due to the ever-increasing connectedness of human beings. Due to technological advances in communications and travel, friendship networks could grow larger and span even greater distances. Karinthy posited that despite great physical distances between the globe's individuals, the growing density of human networks made the actual social distance far smaller.

As a result of this hypothesis, Karinthy's characters believed that any two individuals could be connected through at most five acquaintances. In his story, the characters create a game out of this notion. He writes:

A fascinating game grew out of this discussion. One of us suggested performing the following experiment to prove that the population of the Earth is closer together now than they have ever been before. We should select any person from the 1.5 billion inhabitants of the Earth—anyone, anywhere at all. He bet us that, using no more than five individuals, one of whom is a personal acquaintance, he could contact the selected individual using nothing except the network of personal acquaintances [2].

This idea both directly and indirectly influenced a great deal of early thought on social networks. Thus, Karinthy is often regarded as the origin of the notion of Six Degrees of Separation [3].

[edit] Stanley Milgram's small world experiments

Stanley Milgram was an American researcher in experimental social psychology at Harvard University in Boston, USA. Beginning in 1967, he began a widely-publicized set of experiments to investigate the so-called "small world problem." This problem was rooted in many of the same observations made decades earlier by Karinthy. That is, Milgram and other researchers of the era were fascinated by the interconnectedness and "social capital" of human networks. While it is unknown how directly Milgram was influenced by Karinthy's work, the similarities between the two authors are remarkable [3]. However, while Karinthy spoke in abstract and fictional terms, Milgram's experiments provided evidence supporting the claim of a "small world." His study results showed that people in the United States seemed to be connected by approximately six friendship links, on average. Although Milgram reportedly never used the term "Six Degrees of Separation," his findings likely contributed to the term's widespread credence. Since these studies were widely publicized, Stanley Milgram is also, like Karinthy, often attributed as the origin of the notion of Six Degrees.

[edit] Recent attempts to confirm the six degrees hypothesis

[edit] Internet and computer networks

In 2001, Duncan Watts, a professor at Columbia University, attempted to recreate Milgram's experiment on the internet, using an e-mail message as the "package" that needed to be delivered, with 48,000 senders and 19 targets (in 157 countries). Watts found that the average (though not maximum) number of intermediaries was around six. This finding is surprising, given the worldwide nature of the Internet.

It has been suggested by some commentators that interlocking networks of computer mediated lateral communication could diffuse single messages to all interested users worldwide as per the 6 degrees of separation principle via Information Routing Groups, which are networks specifically designed to exploit this principle and lateral diffusion.

[edit] Genealogy studies

The term "six degrees of separation" is often distorted to indicate that six generations is the maximum extent to which everyone in the world is related. This has been disproved in numerous genealogy circles, since six generations translates roughly to 250 years. It has been calculated, more accurately, that the maximum relationship a person living in the modern age can be to someone else, anywhere in the world, is 30-32 generations removed which is roughly 1200 years of ancestry.[citation needed]

[edit] Popularization of the term

No longer limited strictly to academic or philosophical thinking, the notion of Six Degrees recently has become influential throughout popular culture. Further advances in communication technology—and particularly the Internet—have drawn great attention to social networks and human interconnectedness. As a result, many popular media sources have addressed the term. The following provide a brief outline of the ways such ideas have shaped popular culture.

[edit] John Guare's Six Degrees of Separation

John Guare, an American playwright, is the author of the 1990 Six Degrees of Separation. This play, which was adapted for the screen in 1993, launched the term into everyday lexicon. It is considered to be Guare's most widely-known play.

The piece ruminates upon the idea that any two individuals are connected by at most six others. And, similar to Karinthy's 1929 "Chains" (see section above), this leads the characters to feelings of awe, and in some ways, grief. As one of the characters states,

I read somewhere that everybody on this planet is separated by only six other people. Six degrees of separation between us and everyone else on this planet. The President of the United States, a gondolier in Venice, just fill in the names. I find it extremely comforting that we're so close. I also find it like Chinese water torture, that we're so close because you have to find the right six people to make the right connection... I am bound, you are bound, to everyone on this planet by a trail of six people [4].

Although this idea had been circulating in various forms for decades, it is this piece that is said to be responsible for popularizing, if not coining the phrase "six degrees of separation." Following Guare's lead, Many future television and film sources would later incorporate the notion into their stories.

Interestingly, J.J. Abrams, the executive producer of television series Six Degrees and Lost, played the role of Doug in the film adaptation of this play. Many of the play's themes are apparent in his television shows (see below).

[edit] The Kevin Bacon game

The game "Six Degrees of Kevin Bacon" was invented in 1994 by two students at Albright College in Reading, Pennsylvania, as a play on the concept: the goal is to link any actor to Kevin Bacon through no more than six connections, where two actors are connected if they have appeared in a movie together.

[edit] SixDegrees.org

On January 18, 2007, Kevin Bacon launched SixDegrees.org, a web site that builds on the popularity of the "small world phenomenon" to create a charitable social network and inspire giving to charities online. Bacon started the network with celebrities who are highlighting their favorite charities – including Kyra Sedgwick (Natural Resources Defense Council), Nicole Kidman (UNIFEM), Ashley Judd (YouthAIDS), Bradley Whitford and Jane Kaczmarek (Clothes off Our Back), Dana Delany (Scleroderma Research Foundation), Robert Duvall (Pro Mujer), Rosie O'Donnell (Rosie's For All Kids Foundation), and Jessica Simpson (Operation Smile) - and he encouraged everyone to be celebrities for their own causes by joining the Six Degrees movement.

"SixDegrees.org is about using the idea that we are all connected to accomplish something good," said Bacon. "It is my hope that Six Degrees will soon be something more than a game or a gimmick. It will also be a force for good, by bringing a social conscience to social networking." The game, 'Six Degrees of Kevin Bacon,' made the rounds of college campuses over the past decade and lived on to be a shorthand term for the small world phenomenon.

Bacon created SixDegrees.org in partnership with the nonprofit, Network for good, AOL, and Entertainment Weekly. Through SixDegrees.org, which builds on Network for Good's giving system for donating to more than one million charities online and AOL's AIM Pages social networking service, people can learn about and support the charities of celebrities or fundraise for their own favorite causes with their own friends and families. Bacon will match the charitable dollars raised by the top six non-celebrity fundraisers with grants of up to $10,000 each[5]

[edit] Mathematics

Mathematicians use an analogous notion of collaboration distance (see AMS): two persons are linked if they are coauthors of an article. The collaboration distance with mathematician Paul Erdős is called the Erdős number. Erdős-Bacon numbers are a further extension of the same thinking.

[edit] Film and television

  • Six Degrees of Separation is a 1993 film drama featuring Will Smith, Donald Sutherland and Stockard Channing, about a fast-talking young man (Smith's entrée into mainstream cinema) who, out of the blue, prevails upon the good graces of a non-plussed NYC couple in the wake of his supposed mugging in Central Park, claiming to be Sidney Poitier's son and masquerading flamboyantly as a close friend & classmate of their Harvard-enrolled kids, and in the process upsetting their shallow uppercrust world.
  • Six Degrees is a 2006 television series on ABC in the US. The show details the experiences of six New Yorkers who go about their lives without realizing they are affecting each other, and gradually meet one another. [4]
  • The seventh episode of the first season of Battlestar Galactica was named "Six Degrees of Separation."
  • The television program Lost also explores the idea of six degrees of separation, as almost all the characters have randomly met each other before the crash or someone the other characters know. On the Season 2 Bonus Material DVD, there is a special feature called "The Lost Connections". It has an intro that mentions Karinthy Frigyes and explains the theory, showing photographs of random people and proposing that "you or someone you know" probably knows them. The actual feature is an animated interface of video clips of character connections, the frames of the videos connected by multi-colored wires.
  • Lonely Planet Six Degrees is a TV travel show that uses the "six degrees of separation concept: the hosts, Asha Gill and Toby Amies, explore various cities through its people, by following certain personalities of the city around and being introduced by them to other personalities.
  • Another notable reference should be given to the show "The L Word" - which although not directly referencing to the 6 degrees of separation, deals with this theme in the 'web' in which all characters are linked via sexual events to others. Alice Pieszecki (played by Leisha Hailey) is the originator of this concept, and indeed the initial web is shown in her home, on a whiteboard before eventually being translated to the internet.

[edit] Other

[edit] See also

[edit] Notes and references

  1. ^ Newman, Mark, Albert-László Barabási, and Duncan J. Watts. 2006. The Structure and Dynamics of Networks. Princeton, NJ: Princeton University Press.
  2. ^ Karinthy, Frigyes. Chain-Links. Translated from Hungarian and annotated by Adam Makkai and Enikö Jankó.
  3. ^ a b Barabási, Albert-László. 2003. Linked: How Everything is Connected to Everything Else and What It Means for Business, Science, and Everyday Life. New York: Plume.
  4. ^ Memorable quotes from Six Degrees of Separation. Accessed Nov. 11, 2006 from IMDB.com.
  5. ^ Jan. 18, 2007 press release from Network for Good. [1].
  6. ^ Billion To One website
  7. ^ Find Satoshi project
  8. ^ [2]
  9. ^ [3]

[edit] External links