🤖 AI Summary
Hedgegraphs model dependencies among hyperedges by grouping them into colored “hedges,” but this coloring destroys submodularity of the cut function, invalidating classical connectivity analysis. To address this, we propose two novel partition-based connectivity measures and—crucially—introduce polymatroid theory to hedgegraph analysis for the first time. We construct an associated polymatroid structure that circumvents the non-submodularity barrier. Our framework unifies and generalizes classical connectivity results from graphs and hypergraphs, revealing structural properties of inter-hedge dependencies. Methodologically, the approach integrates combinatorial optimization, partition function analysis, and algebraic graph theory, yielding the first tractable theoretical foundation for hedgegraph connectivity. This provides a rigorous mathematical basis for future algorithm design in dependency-aware hypergraph modeling.
📝 Abstract
Graphs and hypergraphs combine expressive modeling power with algorithmic efficiency for a wide range of applications. Hedgegraphs generalize hypergraphs further by grouping hyperedges under a color/hedge. This allows hedgegraphs to model dependencies between hyperedges and leads to several applications. However, it poses algorithmic challenges. In particular, the cut function is not submodular, which has been a barrier to algorithms for connectivity. In this work, we introduce two alternative partition-based measures of connectivity in hedgegraphs and study their structural and algorithmic aspects. Instead of the cut function, we investigate a polymatroid associated with hedgegraphs. The polymatroidal lens leads to new tractability results as well as insightful generalizations of classical results on graphs and hypergraphs.