Download the full-sized PDF of Results on Set Representations of GraphsDownload the full-sized PDF


Download  |  Analytics

Export to: EndNote  |  Zotero  |  Mendeley


This file is in the following communities:

Faculty of Graduate Studies and Research


This file is in the following collections:

Theses and Dissertations

Results on Set Representations of Graphs Open Access


Other title
intersection graphs
combinatorial games
graph theory
Type of item
Degree grantor
University of Alberta
Author or creator
Enright, Jessica Anne
Supervisor and department
Stewart, Lorna (Computing Science)
Examining committee member and department
Hayward, Ryan (Computing Science)
Shirvani, Mazi (Mathematics)
Rudnicki, Piotr (Computing Science)
Zaiane, Osmar (Computing Science)
Stewart, Lorna (Computing Science)
Department of Computing Science

Date accepted
Graduation date
Doctor of Philosophy
Degree level
A set representation of a graph is an assignment of sets to vertices such that two vertices are adjacent if and only if their assigned sets have some specified relationship. We give several results related to set representations of graphs. We show that recognising the overlap and intersection graphs of subtrees in some types of trees is NP-hard. The subtree overlap graphs (SOGs) generalise many other graph classes with set rep- resentation characterisations. The complexity of recognising SOGs is open. The complexities of recognising many subclasses of SOGs are known. We consider several subclasses of SOGs by restricting the underlying tree. For a fixed integer k ≥ 3, we consider: • the overlap graphs of subtrees in a tree with k leaves, • the overlap graphs of subtrees in trees that can be derived from a given input tree by subdivi- sion and have at least 3 leaves, • the overlap and intersection graphs of paths in a tree with maximum degree k, We show that the recognition problems of these classes are NP-complete. We give characterisations of several subclasses of overlap graphs of subtrees in a tree in terms of filament representations. List colouring with a fixed colour bound of at least three is NP-complete, even on planar bipartite graphs. We give a polynomial-time algorithm for solving list colouring with a fixed colour bound on permutation and interval graphs, two classes with intersection representations. Finally, we describe a class of impartial combinatorial games on graphs using set representations. In these games, the players antagonistically build a set representation of a graph. We give hardness results for determining the winner of a position of these types of games in general, and give polynomial-time algorithms to solve special cases of these games on trees.
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication

File Details

Date Uploaded
Date Modified
Audit Status
Audits have not yet been run on this file.
File format: pdf (Portable Document Format)
Mime type: application/pdf
File size: 2064030
Last modified: 2015:10:12 13:42:56-06:00
Filename: Enright_Jessica_Spring 2012.pdf
Original checksum: 641264ebff4c41d2d9b10f5739d2e1c0
Well formed: true
Valid: true
Status message: File header gives version as 1.4, but catalog dictionary gives version as 1.3
Status message: Too many fonts to report; some fonts omitted. Total fonts = 1356
Page count: 134
Activity of users you follow
User Activity Date