## Abstract

This paper describes one variation on witness proximity graphs called mutual witness proximity graphs. Two witness proximity graphs are said to be mutual when, given two sets of points A and B, A is the vertex set of the first graph and the witness set of the second one, while B is the witness set of the first graph and the vertex set of the second one. We show that in the union of two mutual witness Delaunay graphs, there are always at least n-22 edges, where n=|A|+|B|, which is tight in the worst case. We also show that if two mutual witness Delaunay graphs are complete, then the sets A and B are circularly separable; if two mutual witness Gabriel graphs are complete, then the sets A and B are linearly separable; but two mutual witness rectangle graphs might be complete, with A and B not linearly separable.

Original language | English (US) |
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Pages (from-to) | 519-523 |

Number of pages | 5 |

Journal | Information Processing Letters |

Volume | 114 |

Issue number | 10 |

DOIs | |

State | Published - Oct 2014 |

## Keywords

- Computational geometry
- Delaunay graphs
- Gabriel graphs
- Proximity graphs
- Rectangle of influence graphs
- Witness graphs

## ASJC Scopus subject areas

- Theoretical Computer Science
- Signal Processing
- Information Systems
- Computer Science Applications