Existing methods for differentiable structure learning in discrete data typically assume that the data are generated from specific structural equation models. However, these assumptions may not align with the true data-generating process, which limits the general applicability of such methods. Furthermore, current approaches often ignore the complex dependence structure inherent in discrete data and consider only linear effects. We propose a differentiable structure learning framework that is capable of capturing arbitrary dependencies among discrete variables. We show that although general discrete models are unidentifiable from purely observational data, it is possible to characterize the complete set of compatible parameters and structures. Additionally, we establish identifiability up to Markov equivalence under mild assumptions. We formulate the learning problem as a single differentiable optimization task in the most general form, thereby avoiding the unrealistic simplifications adopted by previous methods. Empirical results demonstrate that our approach effectively captures complex relationships in discrete data.
翻译:现有的离散数据可微分结构学习方法通常假设数据由特定的结构方程模型生成。然而,这些假设可能与真实的数据生成过程不符,从而限制了此类方法的普适性。此外,当前方法往往忽略离散数据固有的复杂依赖结构,仅考虑线性效应。我们提出了一种可微分结构学习框架,能够捕捉离散变量间的任意依赖关系。我们证明,尽管一般离散模型无法仅从观测数据中识别,但可以刻画所有兼容参数与结构的完整集合。此外,我们在温和假设下建立了直至马尔可夫等价类的可识别性。我们将学习问题以最一般形式表述为单一可微分优化任务,从而避免了先前方法所采用的不切实际的简化。实证结果表明,我们的方法能有效捕捉离散数据中的复杂关系。