Algorithms and Models for the Web Graph

This volume contains the papers presented at WAW2015, the 12th Workshop on Algorithms and Models for the Web-Graph held during December 10–11, 2015, in Eindhoven.\ud There were 24 submissions. Each submission was reviewed by at least one, and on average two, Program Committee members. The committee decided to accept 15 papers. The program also included three invited talks, by Mariana Olvera-Cravioto (Columbia University), Remco van der Hofstad (Eindhoven University of Technology), and Paul Van Dooren (Catholic University of Louvain). This year the workshop was accompanied by a school aimed at PhD students, postdocs, and young researchers. The speakers of the school were Dean Eckles (Facebook), David F. Gleich, Kyle Kloster (Purdue University), and Tobias Müller (Utrecht University). \ud Analyzing data as graphs has transitioned from a minor subfield into a major industrial effort over the past 20 years. The World Wide Web was responsible for much of this growth and the Workshop on Algorithms and Models for the Web-Graph (WAW) originally started by trying to understand the behavior and processes underlying the Web. It has since outgrown these roots and WAW is now one of the premier venues for original research work that blends rigorous theory and experiments in analyzing data as a graph. We believe that the 12th WAW continues the high standards of the earlier workshops and as a result maintains the tradition of a small, high-quality workshop.\ud The organizers would like to thank EURANDOM, the NETWORKS grant, Microsoft Research, and Google for contributing to the financial aspect of the workshop. We would especially like to thank EURANDOM and the Eindhoven University of Technology for their hospitality and smooth organization of the material aspects of the conference such as drinks/food, accommodation for speakers, etc.\ud The editorial aspects of the proceedings were supported via the online tool EasyChair. It made our work easier and smoother