提出混合确定性扩散模型,解决异构表格数据缺失值填补难题。
MissHDD: Hybrid Deterministic Diffusion for Hetrogeneous Incomplete Data Imputation
- 分离数值与类别变量,分别用确定性与离散路径扩散建模。
- 在多个真实数据集上优于现有方法,尤其在非随机缺失场景表现更稳。
- 适合处理含数值、类别、离散变量的复杂表格数据填补任务。
真实世界表格数据中常存在缺失值,且数值、类别和离散属性共存,这种异构结构给现有基于扩散的填补模型带来挑战。这些模型通常假设特征空间同质,依赖随机去噪轨迹,难以保持条件一致性,易导致类别变量信息坍塌或数值变量更新不稳定。单一扩散过程不足以应对混合类型表格数据。本文提出一种混合确定性扩散框架,将异构特征分为两个互补生成通道:基于连续DDIM的通道为数值变量提供高效稳定的确定性去噪;受漏洞启发的离散潜在路径扩散通道在不脱离有效样本流形的前提下建模类别和离散变量。两个通道在统一的条件填补目标下训练,实现对混合类型缺失数据的连贯重建。在多个真实数据集上的实验表明,该框架在各类缺失机制(MCAR、MAR、MNAR)下均达到更高填补精度、更稳定采样轨迹和更强鲁棒性,显著优于现有扩散及经典方法。结果证明结构感知的扩散过程对推进深度学习在缺失表格数据中的应用至关重要。
原文摘要 · Abstract (English)
Incomplete data are common in real-world tabular applications, where numerical, categorical, and discrete attributes coexist within a single dataset. This heterogeneous structure presents significant challenges for existing diffusion-based imputation models, which typically assume a homogeneous feature space and rely on stochastic denoising trajectories. Such assumptions make it difficult to maintain conditional consistency, and they often lead to information collapse for categorical variables or instability when numerical variables require deterministic updates. These limitations indicate that a single diffusion process is insufficient for mixed-type tabular imputation. We propose a hybrid deterministic diffusion framework that separates heterogeneous features into two complementary generative channels. A continuous DDIM-based channel provides efficient and stable deterministic denoising for numerical variables, while a discrete latent-path diffusion channel, inspired by loopholing-based discrete diffusion, models categorical and discrete features without leaving their valid sample manifolds. The two channels are trained under a unified conditional imputation objective, enabling coherent reconstruction of mixed-type incomplete data. Extensive experiments on multiple real-world datasets show that the proposed framework achieves higher imputation accuracy, more stable sampling trajectories, and improved robustness across MCAR, MAR, and MNAR settings compared with existing diffusion-based and classical methods. These results demonstrate the importance of structure-aware diffusion processes for advancing deep learning approaches to incomplete tabular data.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。