53 lines
948 B
Markdown
53 lines
948 B
Markdown
# Extras
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## WebRTC
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Read GCC
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## PageRank
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Whenever we need to search for a result on Google, this one
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of the most famous algorithm used.
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First we take some pages and all the links available
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on that page linking to the other gathered pages:
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```bash
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p1, p2, p3, p4, ..., pn
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# Links found on the page
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p1:
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- a1 -> p2
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- a3 -> p4
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...
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- al -> p8
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p2:
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...
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```
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Then we make an oriented graph where all the `points` are pages
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and links are `arrows` pointing to the ***landing page***
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### Variables
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- $B_p$ : Set of pages that backlinks to $p$
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- $|a|$ : Cardinality of $a$ | Number of outgoing links from
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$a$
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### Formula
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$$
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rank_k(p) = \sum_{a \in B_p}\frac{
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rank_{k-1}(a)
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}{
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|a|
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} \in [0, \dots, 1]
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$$
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Here the state is composed of all ranks for our gathered pages.
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If $| rank_k(p) - rank_{k-1}(p)| < \epsilon$ we will stop
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iterating.
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At time $k = 0$ all pages have the same importance that is
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$rank_0(p) = \frac{1}{n}$
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## Economic System
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