Mathematics – Algebraic Geometry
Scientific paper
2007-04-06
Mathematics
Algebraic Geometry
30 page, 4 figures
Scientific paper
Conditional independence models in the Gaussian case are algebraic varieties in the cone of positive definite covariance matrices. We study these varieties in the case of Bayesian networks, with a view towards generalizing the recursive factorization theorem to situations with hidden variables. In the case when the underlying graph is a tree, we show that the vanishing ideal of the model is generated by the conditional independence statements implied by graph. We also show that the ideal of any Bayesian network is homogeneous with respect to a multigrading induced by a collection of upstream random variables. This has a number of important consequences for hidden variable models. Finally, we relate the ideals of Bayesian networks to a number of classical constructions in algebraic geometry including toric degenerations of the Grassmannian, matrix Schubert varieties, and secant varieties.
No associations
LandOfFree
Algebraic geometry of Gaussian Bayesian networks does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Algebraic geometry of Gaussian Bayesian networks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Algebraic geometry of Gaussian Bayesian networks will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-700190