Bridging the inference gap in Mutimodal Variational Autoencoders
This addresses the inference gap in multimodal data integration for applications like medical diagnosis and autonomous vehicles, representing a strong specific gain.
The paper tackles the problem of generating unobserved modalities from observed ones in Multimodal Variational Autoencoders by proposing a novel interpretable model that learns joint and conditional distributions without mixture aggregation, achieving state-of-the-art results on benchmark datasets.
From medical diagnosis to autonomous vehicles, critical applications rely on the integration of multiple heterogeneous data modalities. Multimodal Variational Autoencoders offer versatile and scalable methods for generating unobserved modalities from observed ones. Recent models using mixturesof-experts aggregation suffer from theoretically grounded limitations that restrict their generation quality on complex datasets. In this article, we propose a novel interpretable model able to learn both joint and conditional distributions without introducing mixture aggregation. Our model follows a multistage training process: first modeling the joint distribution with variational inference and then modeling the conditional distributions with Normalizing Flows to better approximate true posteriors. Importantly, we also propose to extract and leverage the information shared between modalities to improve the conditional coherence of generated samples. Our method achieves state-of-the-art results on several benchmark datasets.