A (k+3)/2-approximation algorithm for monotone submodular k-set packing and general k-exchange systems

We consider the monotone submodular k-set packing problem in the context of the more general problem of maximizing a monotone submodular function in a k-exchange system. These systems, introduced by Feldman et al. [9], generalize the matroid k-parity problem in a wide class of matroids and capture many other combinatorial optimization problems. We give a deterministic, non-oblivious local search algorithm that attains an approximation ratio of (k + 3)/2 + for the problem of maximizing a monotone submodular function in a k-exchange system, improving on the best known result of k + , and answering an open question posed by Feldman et al. 1998 ACM Subject Classification F.2.2 Nonnumerical Algorithms and Problems