Theory of Computing Systems | 2019
Guest Editorial: Special Issue on Approximation and Online Algorithms
Abstract
Online algorithms need to make decisions based on information that is provided to them as the algorithms execute, without knowledge of the information that will be provided to them in the future. This uncertainty makes the design of online algorithms very challenging. Approximation algorithms face a different kind of challenges as they need to find the best solutions for problems that have very large solution spaces. This special issue of Theory of Computing Systems is devoted to the publication of a selected set of papers that were presented at the 15th International Workshop on Approximation and Online Algorithms (WAOA 2017) which took place in Vienna, Austria, September 7-8 of 2017. Each one of the 23 papers accepted for presentation at the workshop was reviewed by at least 3 members of the program committee. The program committee invited the authors of the four best papers presented at the workshop to write full versions of their papers and to submit them to the special issue. Each one of these papers was thoroughly reviewed by two experts, in accordance with the high standards of this journal. In “Lower bounds for several online variants of bin packing”, the problem of packing a set of items of different sizes into unit size bins is studied. The bin packing problem is a fundamental problem in optimization that has been extensively studied, partly due to its large number of applications . The authors show how to use a