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| == Abstract == | | == Abstract == |
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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. | + | I will talk about some of the statistical properties of the G(n,p) graph model, due to Erdos and Renyi.<br/> |
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| 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. | | 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: | | 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. | + | (1) When p=d/n for some constant d, the number of triangles in G(n,p) is independent of n.<br/> |
− | | + | (2) The property that G(n,p) has diameter two has a sharp threshold at p = \sqrt(\dfrac{2\ln n}{n}).<br/> |
− | (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 of isolated vertices in G(n,p) has a sharp threshold at p = \dfrac{\ln n}{n}. <br/> |
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− | (3) The disappearance of 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. | | (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 | | I will be covering material from the following book: http://www.cs.cornell.edu/jeh/book11April2014.pdf |