Three counter-examples on semi-graphoids Academic Article uri icon

abstract

  • Semi-graphoids are combinatorial structures that arise in statistical learning theory. They are equivalent to convex rank tests and to polyhedral fans that coarsen the reflection arrangement of the symmetric group Sn. In this paper we resolve two problems on semi-graphoids posed in Studen's book (2005), and we answer a related question of Postnikov, Reiner and Williams on generalized permutohedra. We also study the semigroup and the toric ideal associated with semi-graphoids.

published proceedings

  • COMBINATORICS PROBABILITY & COMPUTING

author list (cited authors)

  • Hemmecke, R., Morton, J., Shiu, A., Sturmfels, B., & Wienand, O.

citation count

  • 12

complete list of authors

  • Hemmecke, Raymond||Morton, Jason||Shiu, Anne||Sturmfels, Bernd||Wienand, Oliver

publication date

  • March 2008