Difference between revisions of "CATS-Oct-17-2014"

From Theory
(Created page with "== Title == Random Graphs == Speaker == Amit Chavan == Abstract == Chapter 3 from the Hopcroft-Kannan book - http://www.cs.cornell.edu/jeh/book11April2014.pdf")
 
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== Abstract ==
 
== Abstract ==
Chapter 3 from the Hopcroft-Kannan book - http://www.cs.cornell.edu/jeh/book11April2014.pdf
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I will talk about some of the statistical properties of the G(n,p) graph model, due to Erdos and Renyi. This model has two parameters: the number of vertices (n), and the edge probability (p). For each pair of vertices, u and v, p is the probability that the edge (u,v) is present, independent of all other edges.
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We will show that such a random graph has many interesting global properties. Namely:
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(1) When p=d/n for some constant d, the number of triangles in G(n,p) is independent of n.
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(2) The property that G(n,p) has diameter two has a sharp threshold at p = \sqrt(\dfrac{2\ln n}{n}).
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(3) The disappearance if isolated vertices in G(n,p) has a sharp threshold at p = \dfrac{\ln n}{n}.
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(4) When p=d/n, d > 1, there is a giant component consisting of a constant fraction of the vertices.
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I will be covering material from the following book: http://www.cs.cornell.edu/jeh/book11April2014.pdf

Revision as of 18:17, 15 October 2014

Title[edit]

Random Graphs

Speaker[edit]

Amit Chavan

Abstract[edit]

I will talk about some of the statistical properties of the G(n,p) graph model, due to Erdos and Renyi. This model has two parameters: the number of vertices (n), and the edge probability (p). For each pair of vertices, u and v, p is the probability that the edge (u,v) is present, independent of all other edges.

We will show that such a random graph has many interesting global properties. Namely: (1) When p=d/n for some constant d, the number of triangles in G(n,p) is independent of n. (2) The property that G(n,p) has diameter two has a sharp threshold at p = \sqrt(\dfrac{2\ln n}{n}). (3) The disappearance if isolated vertices in G(n,p) has a sharp threshold at p = \dfrac{\ln n}{n}. (4) When p=d/n, d > 1, there is a giant component consisting of a constant fraction of the vertices.

I will be covering material from the following book: http://www.cs.cornell.edu/jeh/book11April2014.pdf