The Google Matrix
 
 
To model the behavior of a random web surfer, Google forms the matrix:
     G = αS + (1 - α)Iv,   where
 0≤α<1 
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The damping factor, α, in the Google matrix indicates that random web surfers move to a different webpage by some means other than selecting a link with probability 
1-α.
  
 I, a column vector of ones 
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  For example, 
I=(1 1 1 1)T. 
  
 v, a row probability distribution vector  
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The majority of experiments performed during the development of the PageRank algorithm used 
α=0.85 and v=(1/n 1/n ...1/n). 
Assigning the uniform vector for v suggests web surfers randomly choose new webpages to view when not selecting links. 
   
 
 
  
   
Since each element Gij of G lies between 0 and 1 (0≤Gij≤1) and the sum of elements in each row of G is 1.
 
The following gives an example of G calculation for the web graph on the right.
   
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 G = αS + (1 - α)Iv
            0.00  1.00  0.00  0.00                1
   = 0.85×[ 0.00  0.00  1.00  0.00 ] + (1-0.85)×[ 1 ]×[ 0.25 0.25 0.25 0.25 ]
            0.50  0.00  0.00  0.50                1
            0.25  0.25  0.25  0.25                1
       0.0000  0.8500  0.0000  0.0000       0.0375  0.0375  0.0375  0.0375
   = [ 0.0000  0.0000  0.8500  0.0000 ] + [ 0.0375  0.0375  0.0375  0.0375 ]
       0.4250  0.0000  0.0000  0.4250       0.0375  0.0375  0.0375  0.0375
       0.2125  0.2125  0.2125  0.2125       0.0375  0.0375  0.0375  0.0375
       0.0375  0.8875  0.0375  0.0375         3/80   71/80    3/80    3/80
   = [ 0.0375  0.0375  0.8875  0.0375 ] = [   3/80    3/80   71/80    3/80 ]
       0.4625  0.0375  0.0375  0.4625        37/80    3/80    3/80   37/80
       0.2500  0.2500  0.2500  0.2500         1/4     1/4     1/4     1/4
 
 
  
   
          
     Once in a blue moon (very rarely)      
           you see the Aurora here, but it is not like farther north.
         
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