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Given nodes $A,B$ and $C$. with $A \rightarrow A$, $A\rightarrow B$, $B \rightarrow B$, $C \rightarrow A$, $C \rightarrow C$ where the arrows represent outgoing links from left and incoming links to the node on the right. I'm supposed to find the pagerank of each of the nodes.

My solution: Using the formula PR(i)= $\sum_{j\in B_u}$ $\frac{PR(j)}{L(j)}$ and assuming that each node initial outgoing link has $0.25$ value:

$PR(A)= \frac{0.25}{2} + \frac{0.25}{2} = 0.25$

$PR(B)= \frac{0.25}{2} = 0.125$

$PR(C)= 0$

Where I'm stuck:

  1. In $L(j)$ do I count the returning links also as out-going links? In my answer I have considered them.

  2. When there are no incoming links is the $PR$ of that node $0$ or is initial_value+incoming_links_value? As in node $C$.

Thank you!

share|cite|improve this question
What do you mean by $B_u$? What is $L()$? – oks Feb 15 '13 at 14:03
@oks $B_u$ is the set of incoming links to node i. L(j) is the number of outgoing links from node j. – tutak Feb 15 '13 at 14:10

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