In 1957 W.M. Hirsch conjectured that every d-polytope with n facets has edge-diameter at most n ? d. Recently Holt and Klee constructed polytopes which meet this bound for a number of (d; n) pairsâ€¦ (More)

We investigate the following vertex percolation process. Starting with a random regular graph of constant degree, delete each vertex independently with probability p, where p = nâˆ’Î± and Î± = Î±(n) isâ€¦ (More)

Thirty years ago the connection was established between the presence of nonrevisiting paths in a d-polytope and the polytopeâ€™s edge-diameter. The operation of wedging was used to establish theâ€¦ (More)

Since 1970 vector-space models have been used for information retrieval from unstructured text. The initial simple vector-space models suffered the same problems encountered today in searching theâ€¦ (More)