Building confidence regions for Reeb graphs using the interleaving distance

We develop confidence regions for Reeb graphs from finite samples using the interleaving distance. Given a point cloud equipped with a filter function, we construct a finite proximity graph, extend the filter linearly, and use the Reeb cosheaf of the resulting filtered graph as the primary estimator. Mapper graphs are then treated as controlled cover-based coarsenings of this estimator, separating the statistical approximation problem from the visualization problem. We prove stability bounds for the Reeb estimators obtained both using intrinsic and extrinsic metrics, the latter under positive-reach assumptions, and derive interleaving-distance confidence regions from either $(a,b)$-standard sampling assumptions or subsampling-based Hausdorff scale estimates. We also compare this object-level metric viewpoint with persistence-based guarantees by showing that the extended-persistence pseudometric is bounded by twice the interleaving distance, with sharp constant $1$ for the $H_0$-related components. Numerical experiments illustrate how statistically significant features can be identified and then projected to Mapper graphs for interpretation.