Efficient Neural Causal Discovery without Acyclicity Constraints

Phillip Lippe, Taco Cohen, Efstratios Gavves

Keywords: Causal discovery, structure learning

Abstract: Learning the structure of a causal graphical model using both observational and interventional data is a fundamental problem in many scientific fields. A promising direction is continuous optimization for score-based methods, which, however, require constrained optimization to enforce acyclicity or lack convergence guarantees. In this paper, we present ENCO, an efficient structure learning method for directed, acyclic causal graphs leveraging observational and interventional data. ENCO formulates the graph search as an optimization of independent edge likelihoods, with the edge orientation being modeled as a separate parameter. Consequently, we provide for ENCO convergence guarantees under mild conditions, without having to constrain the score function with respect to acyclicity. In experiments, we show that ENCO can efficiently recover graphs with hundreds of nodes, an order of magnitude larger than what was previously possible, while handling deterministic variables and discovering latent confounders.

One-sentence Summary: We present ENCO, an efficient structure learning method that leverages observational and interventional data and scales to graphs with a thousand variables.

Community Implementations: [ 3 code implementations](https://www.catalyzex.com/paper/arxiv:2107.10483/code)