A (2 + ϵ)-Approximation for Maximum Weight Matching in the Semi-Streaming Model

Abstract

We present a simple deterministic single-pass (2 + ϵ)- Approximation algorithm for the maximum weight matching problem in the semi-streaming model. This improves upon the currently best known approximation ratio of (3:5 + ϵ). Our algorithm uses O(n log2 n) space for constant values of ϵ. It relies on a variation of the local-ratio theorem, which may be of independent interest in the semi-streaming model.