Reed's law

Reed's law

Reed's law is the assertion of David P. Reed that the utility of large , particularly social networks, can scale exponentially with the size of the network.

The reason for this is that the number of possible sub-groups of network participants is 2^N - N - 1 , , where N is the number of participants. This grows much more rapidly than either
* the number of participants, N, or
* the number of possible pair connections, frac{N(N-1)}{2} (which follows Metcalfe's law)so that even if the utility of groups available to be joined is very small on a peer-group basis, eventually the network effect of potential group membership can dominate the overall economics of the system.

Derivation

Given a set "A" of "N" people, it has 2^N possible subsets. This is not difficult to see, since we can form each possible subset by simply choosing for each element of "A" one of two possibilities: whether to include that element, or not.

However, this includes the (one) empty set, and "N" Singletons, which are not properly subgroups. So 2^N - N - 1 subsets remain, which is exponential, like 2^N .

Quote

From David P. Reed's, "The Law of the Pack" (Harvard Business Review, February 2001, pp 23-4):

:" [E] ven Metcalfe's Law understates the value created by a group-forming network [GFN] as it grows. Let's say you have a GFN with n members. If you add up all the potential two-person groups, three-person groups, and so on that those members could form, the number of possible groups equals 2^n. So the value of a GFN increases exponentially, in proportion to 2^n. I call that Reed's Law. And its implications are profound."

See also

* Coase's penguin
* Social capital
* Metcalfe's law
* Sarnoff's law
* Andrew Odlyzko's "Content is Not King"
* List of adages named after people
* List of eponymous laws

References

External links

* [http://www.reed.com/gfn/docs/reedslaw.html That Sneaky Exponential—Beyond Metcalfe's Law to the Power of Community Building]
* [http://www.contextmag.com/archives/199903/digitalstrategy.asp Weapon of Math Destruction: A simple formula explains why the Internet is wreaking havoc on business models.]
* [http://kotisivukone.fi/files/50ajatelmaa.ajatukset.fi/tiedostot/Others/kilkki_kk-law.pdf KK-law for Group Forming Services] , XVth International Symposium on Services and Local Access, Edinburgh, March 2004, presents an alternative way to model the effect of social networks.


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • Reed — can refer to: * REED, a theatre research centre at the University of Toronto, Canada* Edward C. Reed High School, Sparks, Nevada * Reed Airport * Reed College, Portland, Oregon * Reed (Company), group of companies offering employment related… …   Wikipedia

  • Reed, Stanley F. — ▪ United States jurist in full  Stanley Forman Reed  born Dec. 31, 1884, Minerva, near Maysville, Ky., U.S. died April 3, 1980, Huntington, N.Y.       associate justice of the Supreme Court of the United States (1938–57).       Reed was the only… …   Universalium

  • Reed Business Information — is a large business publisher in the United States, United Kingdom, continental Europe, Australia and Asia, often referred to as RBI. It is a division of Reed Elsevier, provides a multitude of paid data services, hosts conferences and publishes… …   Wikipedia

  • Reed Hundt — Reed E. Hundt (born March 3 1948 in Ann Arbor, Michigan) was chairman of the United States Federal Communications Commission from 1993 to 1997. Appointed by President Bill Clinton, he served for most of Clinton s first term. He was succeeded by… …   Wikipedia

  • Reed Brody — (1953 ) est un avocat américain, spécialisé dans la défense des victimes des régimes dictatoriaux. Surnommé « le chasseur de dictateurs », il est conseiller juridique et porte parole de l’organisation Human Rights Watch. Il travaille… …   Wikipédia en Français

  • Reed Smith Richards Butler — LLP was the name of the merged law firm in the United Kingdom created by the 2007 merger of UK firm Richards Butler LLP with US based international firm Reed Smith LLP. From May 2008, the firm has harmonized its brand name across all of its… …   Wikipedia

  • Reed Erickson — (1912 1992) was a transsexual man best known for his philanthropy.In 1964 he launched the Erickson Educational Foundation (EEF), a nonprofit philanthropic organization funded and controlled entirely by Erickson himself. The Erickson Educational… …   Wikipedia

  • Reed Cowan — (born Darrin Reed Cowan July 24, 1972 in Roosevelt, Utah) is a television news anchor in Miami, Florida for WSVN TV. Cowan moved from Salt Lake City to Miami s WSVN after seven years working as an anchor and reporter for KTVX TV in Salt Lake City …   Wikipedia

  • Reed V. Hillman — Reed Hillman (born 1948 in Newton, Massachusetts) was the Republican nominee for Lieutenant Governor for the 2006 gubernatorial election in Massachusetts, as well as a former Massachusetts State Representative. He currently lives in Sturbridge,… …   Wikipedia

  • Reed Gusciora — (* 27. März 1960 in Passaic, New Jersey) ist ein US amerikanischer Politiker (Demokratischen Partei). Nach seiner Schulzeit studierte Gusciora Politikwissenschaften und Internationale Beziehungen an der Katholischen Universität von Amerika und… …   Deutsch Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”