Title
An Experimental Study of Algorithms for Online Bipartite Matching
Abstract
We perform an experimental study of algorithms for online bipartite matching under the known i.i.d input model with integral types. In the last decade, there has been substantial effort in designing complex algorithms to improve worst-case approximation ratios. Our goal is to determine how these algorithms perform on more practical instances rather than worst-case instances. In particular, we are interested in whether the ranking of the algorithms by their worst-case performance is consistent with the ranking of the algorithms by their average-case/practical performance. We are also interested in whether preprocessing times and implementation difficulties that are introduced by these algorithms are justified in practice. To that end, we evaluate these algorithms on different random inputs as well as real-life instances obtained from publicly available repositories. We compare these algorithms against several simple greedy-style algorithms. Most of the complex algorithms in the literature are presented as being non-greedy (i.e., an algorithm can intentionally skip matching a node that has available neighbors) to simplify the analysis. Every such algorithm can be turned into a greedy one without hurting its worst-case performance. On our benchmarks, non-greedy versions of these algorithms perform much worse than their greedy versions. Greedy versions perform about as well as the simplest greedy algorithm by itself. This, together with our other findings, suggests that simplest greedy algorithms are competitive with the state-of-the-art worst-case algorithms for online bipartite matching on many average-case and practical input families. Greediness is by far the most important property of online algorithms for bipartite matching.
Year
DOI
Venue
2018
10.1145/3379552
Journal of Experimental Algorithmics
Keywords
Field
DocType
Bipartite graphs,bipartite matching,greedy algorithms,stochastic input models
Online algorithm,Ranking,Bipartite graph,Algorithm,Greedy algorithm,Preprocessor,Mathematics
Journal
Volume
Issue
ISSN
25
1
1084-6654
Citations 
PageRank 
References 
0
0.34
0
Authors
3
Name
Order
Citations
PageRank
Allan Borodin12947658.84
Christodoulos Karavasilis200.34
Denis Pankratov3717.81