Causal discovery for linear causal model with correlated noise: an Adversarial Learning Approach
Mujin Zhou, Junzhe Zhang
TL;DR
This work tackles causal discovery in linear systems with unmeasured confounding by learning a binary causal structure M = (S_B,S_Σ) that encodes both direct and confounding edges. It reframes model selection as minimizing Bayesian free energy, which is equivalent to minimizing the KL divergence between the true data distribution and the model distribution, and solves this via the f-GAN framework with a differentiable relaxation of discrete graph structures using Gumbel-Softmax. The method, fGAN-CD, unifies Bayesian model selection with adversarial learning to recover general ADMGs without restrictive bow-free assumptions, demonstrated on synthetic data with dense confounding where baselines fail. The approach yields state-of-the-art structural recovery and accurate independence constraints, highlighting its potential for causal discovery in singular models and real-world confounded settings.
Abstract
Causal discovery from data with unmeasured confounding factors is a challenging problem. This paper proposes an approach based on the f-GAN framework, learning the binary causal structure independent of specific weight values. We reformulate the structure learning problem as minimizing Bayesian free energy and prove that this problem is equivalent to minimizing the f-divergence between the true data distribution and the model-generated distribution. Using the f-GAN framework, we transform this objective into a min-max adversarial optimization problem. We implement the gradient search in the discrete graph space using Gumbel-Softmax relaxation.
