{ "id": "1810.02041", "version": "v1", "published": "2018-10-04T03:39:49.000Z", "updated": "2018-10-04T03:39:49.000Z", "title": "On connectivity, conductance and bootstrap percolation for a random k-out, age-biased graph", "authors": [ "Hüseyin Acan", "Boris Pittel" ], "comment": "27 pages", "categories": [ "math.CO" ], "abstract": "A uniform attachment graph (with parameter $k$), denoted $G_{n,k}$ in the paper, is a random graph on the vertex set $[n]$, where each vertex $v$ makes $k$ selections from $[v-1]$ uniformly and independently, and these selections determine the edge set. We study several aspects of this graph. Our motivation comes from two similarly constructed, well-studied random graphs: $k$-out graphs and preferential attachment graphs. In this paper, we find the asymptotic distribution of its minimum degree and connectivity, and study the expansion properties of $G_{n,k}$ to show that the conductance of $G_{n,k}$ is of order $(\\log n)^{-1}$. We also study the bootstrap percolation on $G_{n,k}$, where $r$ infected neighbors infect a vertex, and show that $(\\log n)^{-r/(r-1)}$ is a threshold probability of initial infection for the spread of the disease to the whole vertex set.", "revisions": [ { "version": "v1", "updated": "2018-10-04T03:39:49.000Z" } ], "analyses": { "subjects": [ "05C80" ], "keywords": [ "bootstrap percolation", "random k-out", "age-biased graph", "connectivity", "conductance" ], "note": { "typesetting": "TeX", "pages": 27, "language": "en", "license": "arXiv", "status": "editable" } } }