English

Binomial edge ideals and conditional independence statements

Commutative Algebra 2009-10-16 v2

Abstract

We introduce binomial edge ideals attached to a simple graph GG and study their algebraic properties. We characterize those graphs for which the quadratic generators form a Gr\"obner basis in a lexicographic order induced by a vertex labeling. Such graphs are chordal and claw-free. We give a reduced squarefree Gr\"obner basis for general GG. It follows that all binomial edge ideals are radical ideals. Their minimal primes can be characterized by particular subsets of the vertices of GG. We provide sufficient conditions for Cohen--Macaulayness for closed and nonclosed graphs. Binomial edge ideals arise naturally in the study of conditional independence ideals. Our results apply for the class of conditional independence ideals where a fixed binary variable is independent of a collection of other variables, given the remaining ones. In this case the primary decomposition has a natural statistical interpretation

Keywords

Cite

@article{arxiv.0909.4717,
  title  = {Binomial edge ideals and conditional independence statements},
  author = {Juergen Herzog and Takayuki Hibi and Freyja Hreinsdottir and Thomas Kahle and Johannes Rauh},
  journal= {arXiv preprint arXiv:0909.4717},
  year   = {2009}
}
R2 v1 2026-06-21T13:50:37.512Z