25 4 025 5 314159 6 1 if a search engine tends to

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Unformatted text preview: m page? Now assume that a random surfer has a 10% chance to jump to a page (with the target page chosen at random) and that the table of probabilities is given by: Page P1 Probability .2 P2 .1 P3 .05 P4 .0.15 P5 .15 P6 .1 P7 .15 Using P3 as the seed, in what order would the pages be visited when using a breadth ­first searching method? What is the probability of a random surfer ending on P6 after the first iteration? CS100 Review Package Winter 2011 Page 19 of 21 Ranking The following is an example of a contingency table for a search Relevant Irrelevant Returned A B Not Returned C D Using the letters given in the table, what is the calculation for: Precision Recall Which of the following are possible values of precision 1) 0 2) ¼ 3) 0.25 4)  ­0.25 5) 3.14159 6) 1 If a search engine tends to return relevant pages higher in the list than lower down, how can you increase precision? If a search engine tends to return releva...
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This document was uploaded on 04/01/2014.

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