Small components in k-nearest neighbour graphs
نویسنده
چکیده
Let G = Gn,k denote the graph formed by placing points in a square of area n according to a Poisson process of density 1 and joining each point to its k nearest neighbours. In [2] Balister, Bollobás, Sarkar and Walters proved that if k < 0.3043 logn then the probability that G is connected tends to 0, whereas if k > 0.5139 logn then the probability that G is connected tends to 1. We prove that, around the threshold for connectivity, all vertices near the boundary of the square are part of the (unique) giant component. This shows that arguments about the connectivity of G do not need to consider ‘boundary’ effects. We also improve the upper bound for the threshold for connectivity of G to k = 0.4125 logn.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 160 شماره
صفحات -
تاریخ انتشار 2012