Four fundamental graph problems, Minimum vertex cover, Max imum independent set, Minimum dominating set and Maximum cut, are shown to be APX-complete even for cubic graphs. This means that unlessâ€¦ (More)

We investigate the computational complexity of two closely related classes of combinatorial optimization problems for linear systems which arise in various elds such as machine learning, operationsâ€¦ (More)

We prove that maximum three dimensional matching is a MAX SNP-hard problem. If the number of occurrences of elements in triples is bounded by a constant the problem is MAX SNP-complete. Asâ€¦ (More)

The last few years have seen an extremely prolific research activity in the field of design and analysis of approximation algorithms. Actually, the notion of approximation algorithm has beenâ€¦ (More)

The study of the approximability properties of NP-hard optimization problems has recently made great advances mainly due to the results obtained in the field of proof checking. The last importantâ€¦ (More)

An efficient implementation of a part-of-speech tagger for S wedish is described. The stochastic tagger uses a well-established Markov model of the language. The tagger tags 92% of unknown wordsâ€¦ (More)

We study the Max k-Cut problem and its dual, the Abstract-1 Min k-Partition problem. In the Min k-Partition problem, given a graph G = (V, E) and positive edge weights, we want to find an edge set ofâ€¦ (More)