designed an algorithm based on spectral techniques that almost surely finds a clique of size β n hidden in an otherwise random graph. We show that a different algorithm, based on the LovΓ‘sz theta function, almost surely both finds the hidden clique and certifies its optimality. Our algorithm has an
Finding a large hidden clique in a random graph
β Scribed by Noga Alon; Michael Krivelevich; Benny Sudakov
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 177 KB
- Volume
- 13
- Category
- Article
- ISSN
- 1042-9832
No coin nor oath required. For personal study only.
β¦ Synopsis
We consider the following probabilistic model of a graph on n labeled vertices.
Ε½
. First choose a random graph G n, 1r2 , and then choose randomly a subset Q of vertices of size k and force it to be a clique by joining every pair of vertices of Q by an edge. The problem is to give a polynomial time algorithm for finding this hidden clique almost surely for various values of k. This question was posed independently, in various variants, by Jerrum and by Kucera. In this paper we present an efficient algorithm for all k ) cn 0.5 , for Λ0.5 Ε½ . 0.5 any fixed c ) 0, thus improving the trivial case k ) cn log n . The algorithm is based on the spectral properties of the graph.
π SIMILAR VOLUMES
## Abstract A graph is point determining if distinct vertices have distinct neighborhoods. The nucleus of a pointβdetermining graph is the set __G__^O^ of all vertices, __v__, such that __G__β__v__ is point determining. In this paper we show that the size, Ο(__G__), of a maximum clique in __G__ sat