Learning rich representation from data is an important task for deep generative models such as variational auto-encoder (VAE). However, by extracting high-level abstractions in the bottom-up inference process, the goal of preserving all factors of variations for top-down generation is compromised. Motivated by the concept of "starting small", we present a strategy to progressively learn independent hierarchical representations from high- to low-levels of abstractions. The model starts with learning the most abstract representation, and then progressively grow the network architecture to introduce new representations at different levels of abstraction. We quantitatively demonstrate the ability of the presented model to improve disentanglement in comparison to existing works on two benchmark data sets using three disentanglement metrics, including a new metric we proposed to complement the previously-presented metric of mutual information gap. We further present both qualitative and quantitative evidence on how the progression of learning improves disentangling of hierarchical representations. By drawing on the respective advantage of hierarchical representation learning and progressive learning, this is to our knowledge the first attempt to improve disentanglement by progressively growing the capacity of VAE to learn hierarchical representations.

通过渐进式学习独立层级表示，本文提出了一种策略来提高Deep Generative Models如Variational Auto-Encoder的去纠缠性能，该模型从最抽象的表示开始学习，并逐渐增加网络结构以介绍不同层次的表示。在两个基准数据集上，本文通过三个去纠缠度量定量地证明了所提出模型相比于现有作品的改进，包括我们提出的补充相互信息差度量。我们提供了定性和定量的证据，论证了学习进程如何提高分解成层级表示的性能。本文通过同时利用层级表示学习和渐进式学习的优势，是我们目前发现的第一次尝试通过逐步增加VAE的能力来提高去纠缠性。

逐步学习和分离层次表示