Supplementary Material for A polynomial time algorithm for learning nonparametric causal graphs A Reduction to order search

The fact that DAG learning can be reduced to learning a topological sort is well-known. Theorem 3.1 is an immediate corollary of Lemma B.1. For completeness, we include a proof below. In this appendix, we illustrate how Theorem 3.1 can be extended to the case where residual variances Then the order π is identifiable. Before proving this result, we illustrate it with an example.