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Networks

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  1. Network Theory… and other stuff Networks • The Internet may be described as part technology and part human interaction. To describe it as one or the other is not quite accurate. Unlike other technologies, it does not do anything in the absence of the human mind – in fact, the human mind is the sole source of its viability. Accordingly, the destiny of the Net will be determined by the interaction of two adaptive agents: • The systems and software of the Net • Its human users Source: Valovic, “Digital Mythologies”

  2. Network Theory… and other stuff Networks The Web is a Network … Not only that, the Web is complex network… so says Sir Tim Berners-Lee (and just about every other scientist in the world who is doing research on networks or complexity theory). So let’s take this as a given. The Web is a Complex Network

  3. Graphic view of the Web (by tracing links) Each color on this Opte map represents a region; North America, blue; Europe/Middle East/Central Asia/Africa, green; Latin America, yellow; Asia Pacific, red; Unknown, white. (Image: Opte.org) Source: NewScientist.com

  4. Network Theory… and other stuff • Elements of complex systems • They are dynamic in the sense they are constantly changing. • They are adaptive, which is to say they evolve to benefit themselves and to insure their survival. • The adaptations are controlled to some extent by the interactions of the entities that comprise the system. • The control is typically highly dispersed. • They exhibit many levels of organisation. • They are comprised of many niches. • They are self-organising. • New elements or entities emerge from complex systems. • The emergent elements are not necessarily predictable from analysis of the individual parts of the system. • Complex systems are defined by relationships between components more than by describing its constituent parts.

  5. Network Theory… and other stuff • Research published by scientists at Notre Dame in 1999 indicated that there were fundamental attributes of most networks, including the Internet and the Web, in that they: • Exhibited rapid and/or consistent growth. • Exhibited a power law distribution. • Exhibited forms of preferential attachment.

  6. Network Theory… and other stuff Rapid and/or Consistent Growth Netcraft's latest Web survey found 101,435,253 websites in November 2006. Not all of these sites are live: some are "parked" domains, while others are abandoned weblogs that haven't been updated in ages. But even if only half the sites are maintained, there are still more than 100 M sites that people pay to keep running. Total sites across all domains Source: Jakob Nielson http://www.useit.com/alertbox/web-growth.html • As the chart shows, the number of Websites has experienced three growth stages: • 1991-1997: Explosive growth, at a rate of 850% per year. • 1998-2001: Rapid growth, at a rate of 150% per year. • 2002-2006: Maturing growth, at a rate of 25% per year.

  7. Network Theory… and other stuff Rapid and/or Consistent Growth The 100 million site milestone caps an extraordinary year in which the Internet has already added 27.4 million sites, easily topping the previous full-year growth record of 17 million from 2005. The Internet has doubled in size since May 2004, when the survey hit 50 million. Blogs and small business web sites have driven the explosive growth this year, with huge increases at free blogging services at Google and Microsoft. Domain industry juggernauts Go Daddy (U.S.) and 1&1 Internet (Germany) have also seen strong demand for low-priced domain names and shared hosting accounts. Total sites across all domains

  8. Network Theory… and other stuff Power Law Distribution Measured by ‘inbound links’ WSU

  9. Network Theory… and other stuff Power Law Distribution What is a “Normal Distribution”?

  10. Network Theory… and other stuff Power Law Distribution What is a “Normal Distribution”? A normal distribution of data means that most of the examples in a set of data are close to the "average," while relatively few examples tend to one extreme or the other.

  11. Network Theory… and other stuff Power Law Distribution Until relatively recently (the mid 1990’s) it was generally assumed that many (most?) networks exhibited a normal distribution of nodes and edges. A normal distribution of data means that most of the examples in a set of data are close to the "average," while relatively few examples tend to one extreme or the other.

  12. Network Theory… and other stuff Power Law Distribution By 1999 several scientist’s had published papers indicating the nodes of Web did NOT form a normal distribution when measured by the edges (or [inbound] links), but instead formed a ‘Power Law’ distribution. Adamic and Huberman – “The Webs Hidden Order”, Communications of the ACM, 2001 Barabasi and Albert – “Emergence of Scaling in Random Networks”, Science, Vol 256, Oct, 1999 • Power laws as related to websites may be verbally represented as: • a very few sites that rank very high in the number of inbound links; • a larger number of sites with close to median numbers of inbound links; • a great number of sites with very few inbound links. • In short, the Web has many small elements, and few large ones. A few sites have millions of pages but millions of sites have only a few pages. A few sites have millions of inbound links, but millions of sites have only a few inbound links.

  13. Network Theory… and other stuff Power Law Distribution • Power laws as related to websites may be verbally represented as: • a very few sites that rank very high in the number of inbound links; • a larger number of sites with close to median numbers of inbound links; • a great number of sites with very few inbound links.

  14. Network Theory… and other stuff Power Law Distribution Logarithmic scale of distribution of inbound links to websites categorised as ‘Business’ in the dot-com zone Linear representation of distribution of inbound links to websites categorized as ‘Business’ in the dot-com zone. • Power laws as related to websites may be verbally represented as: • a very few sites that rank very high in the number of inbound links; • a larger number of sites with close to median numbers of inbound links; • a great number of sites with very few inbound links.

  15. Network Theory… and other stuff Shallow Web Deep Web This is the Long Tail of the Power Law distribution Power Law Distribution

  16. Network Theory… and other stuff Power Law Distribution

  17. Network Theory… and other stuff Power Law Distribution So the question is – WHY?... Why is there a power law distribution? Why is it important?

  18. The web is a complex network. Networks (esp complex networks) exhibit certain characteristics. A characteristic of a complex net is a power law distribution of inbound links. Inbound links are also important because they are an element of Google’s Page Rank formulation. Power Law distributions are said to form by the mechanism known as preferential attachment. “Rich get richer” “Popularity is attractive” “Site with many links attract many links” But what does ‘preferential attachment’ mean from a business perspective? Does it bestow a competitive edge? How does one get it? How important are links? Network Theory… and other stuff

  19. Network Theory… and other stuff Power Law Distribution So the question is – WHY?... Why is there a power law distribution? Why is it important?

  20. Network Theory… and other stuff Power Law Distribution Why is it important? One reason is that it is in the ‘long tail’ of the power law (or the Deep Web) that much of the Web’s innovation and entrepreneurship take place. This is where the new business models are most likely to emerge and thus this is where they are most likely to be discovered.

  21. Network Theory… and other stuff Power Law Distribution Why is it important? Another reason is that as more and more commerce move to the Web, the dynamics of link accumulation – at both global and local granularities – can strongly influence competition and diversity in business and society. Thus it is incumbent on future business leaders to understand these phenomena.

  22. Network Theory… and other stuff Power Law Distributions Another reason is that as more and more commerce move to the Web, the dynamics of link accumulation – at both global and local granularities – can strongly influence competition and diversity in business and society. Thus it is incumbent on future business leaders to understand these phenomena. So why is there a power law distribution of Websites inbound links on the Web? The simple answer is that ‘popularity is attractive’. Another suggestion is that those ‘first adaptors’ had a huge advantage and accumulated more links. We can speculate that the phenomenon of search engine marketing might have an impact as well. In any event, more links indicate more popularity which equates to greater potential for revenue generation.

  23. Network Theory… and other stuff Power Law Distributions In any event, more links indicate more popularity which equates to greater potential for revenue generation. $$ + = Website plus eyeballs equals revenue (potential)