A lot the material about social networks is familiar from Malcolm Gladwell’s “Tipping Point”. While Malcolm looks at the sociological aspects, I didn’t fully realise the mathematical systems underlying social networks ie. Scale-free networks Concepts like Dunbar’s number (the number of people we can maintain a first name relationship with) are also grouped under the Social Network theories.

What IS interesting is that this ties together not only viral marketing and the concepts in the “Tipping Point”, but also the web, and of particular interest search engine optimisation, and link-building or social media optimisation. There has been a lot of talk about semantic hubs on the web, and network theory helps to make this all clearer. It also ties in with semantic web structuring or “silos”.

Semantic relationships are mapped in the WordNet database, which is presented visually in the Visual Thesarus and this experiment at Sydney University. While we are exploring Semantics in search engines, here is a good summary of how Google is currently using Semantic suggestion