Monday, January 9, 2012

Lecture 2

Since I'll be busy after the lecture I'm posting this beforehand...

The notes and slides for lecture 2 are now up on the course website. The key take-aways from today's lecture are the following 4 interesting properties:

1) Connectivity:  The web has one "giant" connected component and all other connected components are tiny.

2) Diameter: The distance between nodes is quite small (~6 avg. distance between noes in the SCC) and, for at least the beginning decade of the web, grow logarithmically with the size of the graph.

3) Degrees:  The degree distribution is not Normal... Instead it's heavy-tailed.  This means we should expect a few nodes with really "huge" degree and "lots" of nodes with small degree.

4) Clustering:  The web exhibits strong "homophilly", i.e., if A is connected to B and C it is significantly more likely than random for B to be connected to C.

Over the next few lectures we'll see that these properties are "universal", and we'll try to explain why they are so common.

(By the way, I'm excited to see that someone already made their first blog post!)

1 comment:

  1. Well, it seems as though the room was double booked, so I'll work to resolve that and let you know via the blog & website when things get settled.