Page Rank & Community detection
Page Rank Let $G = (V, E)$ be a web graph. Each node $v \in V$ represents a web page, while there is a directed edge from $u \in V$ to $v \in V$ if $u$ has a hyperlink to $v$. The importance of $v$ is proportional to the importance of nodes linking to $v$. Let $\delta_\text{in}(v)$ and $\delta_\text{out}(v)$ be the in and out degrees of $v$ in $G$. Then we can define the matrix $M$ as follows: ...