Linear-time MIS size estimation

Develop a maximal independent set size estimation algorithm for the adjacency-matrix query model that runs in $O(n)$ time.

Background

The paper gives a randomized algorithm that estimates the size of a random-greedy maximal independent set within a (1+ε)(1+\varepsilon) multiplicative factor in O(n4/3/ε2)O(n^{4/3}/\varepsilon^2) time. This improves the previously known O(n3/2/ε2)O(n^{3/2}/\varepsilon^2) bound.

The authors explicitly ask whether the running time can be reduced further to linear in the number of vertices, which would improve upon the paper’s main MIS estimation result.

References

Is there an MIS size estimation algorithm that runs in $O(n)$ time?

— Improved Sublinear Algorithms for Maximal Independent Set and Metric Steiner Forest  (2610.06053 - Mahabadi et al., 5 Oct 2026) in Section 6, “Open questions”