Consider the following pages and the set of web pages that they link to: Page A
ID: 3548967 • Letter: C
Question
Consider the following pages and the set of web pages that they link to:
Page A points to page C.
Page B points to page C.
Page C points to page D.
Consider running the PageRank algorithm on this subgraph of pages. Assume d = 0.85. Simulate the algorithm for three iterations, assuming that we start at Page A. Show the page rank scores for each page for each iteration. Order the elements in the vectors in the sequence: A, B, C, D.
use this way in your computations for this question
Explanation / Answer
At t=0 PR(A) = PR(B) = PR(C) = PR(D) = 0.25
At t=1 PR(A;1) = (1-0.85)/4 = 0.0625, PR(B;1) = (1-0.85)/4 = 0.0625,
PR(C;1) = (1-0.85)/4 + 0.85*( PR(A;0)/1 + PR(B;0)/1 ) = 0.0625 + 0.85*0.5 = 0.4875
PR(D;1) = (1-0.85)/4 + 0.85*( PR(C;0)/1) = 0.0625 + 0.85*0.25 = 0.275
PR(A;2) = 0.0625, PR(B;2) = 0.0625
PR(C;2) = 0.0625 + 0.85*(PR(A;1)/1 + PR(B;1)/1) = 0.0625 + 0.85*0.125 = 0.16875
PR(D;2) = 0.0625 + 0.85*(PR(C;1)/1) = 0.0625 + 0.85*(0.4875) = 0.4768
PR(A;3) = 0.0625, PR(B;3) = 0.0625
PR(C;3) = 0.16875
PR(D;3) = 0.0625 + 0.85*(PR(C;2)/1) = 0.0625 + 0.85*(0.4768) = 0.4678