English

The Global Markov Property for a Mixture of DAGs

Statistics Theory 2019-09-16 v2 Statistics Theory

Abstract

Real causal processes may contain feedback loops and change over time. In this paper, we model cycles and non-stationary distributions using a mixture of directed acyclic graphs (DAGs). We then study the conditional independence (CI) relations induced by a density that factorizes according to a mixture of DAGs in two steps. First, we generalize d-separation for a single DAG to mixture d-separation for a mixture of DAGs. We then utilize the mixture d-separation criterion to derive a global Markov property that allows us to read off the CI relations induced by a mixture of DAGs using a particular summary graph. This result has potentially far reaching applications in algorithm design for causal discovery.

Keywords

Cite

@article{arxiv.1909.05418,
  title  = {The Global Markov Property for a Mixture of DAGs},
  author = {Eric V. Strobl},
  journal= {arXiv preprint arXiv:1909.05418},
  year   = {2019}
}