TY - JOUR
T1 - Continual Unsupervised Generative Modeling
AU - Ye, Fei
AU - Bors, Adrian Gheorghe
N1 - This is an author-produced version of the published paper. Uploaded in accordance with the University’s Research Publications and Open Access policy.
PY - 2025/4/25
Y1 - 2025/4/25
N2 - Variational Autoencoders (VAEs), can achieve remarkable results in single tasks learning of data representations, image generation, and image-to-image translation among others. However, VAEs suffer from loss of information when aiming to continuously learn a sequence of different data domains. These are caused by the catastrophic forgetting, which affects all machine learning methods. This paper addresses the problem of catastrophic forgetting by developing a new theoretical framework which derives an upper bound to the negative sample log-likelihood when continuously learning sequences of tasks. These theoretical derivations provide new insights into the forgetting behavior of networks, showing that their optimal performance is achieved when a dynamic mixture expansion model adds new components whenever learning new tasks. In our approach we optimize the model size by introducing the Dynamic Expansion Graph Model (DEGM) that dynamically builds a graph structure promoting the positive knowledge transfer when learning new tasks. In addition, we propose a Dynamic Expansion Graph Adaptive Mechanism (DEGAM) that generates adaptive weights to regulate the graph structure, further improving the positive knowledge transfer effectiveness. Experimental results show that the proposed methodology performs better than other baselines in continual learning.
AB - Variational Autoencoders (VAEs), can achieve remarkable results in single tasks learning of data representations, image generation, and image-to-image translation among others. However, VAEs suffer from loss of information when aiming to continuously learn a sequence of different data domains. These are caused by the catastrophic forgetting, which affects all machine learning methods. This paper addresses the problem of catastrophic forgetting by developing a new theoretical framework which derives an upper bound to the negative sample log-likelihood when continuously learning sequences of tasks. These theoretical derivations provide new insights into the forgetting behavior of networks, showing that their optimal performance is achieved when a dynamic mixture expansion model adds new components whenever learning new tasks. In our approach we optimize the model size by introducing the Dynamic Expansion Graph Model (DEGM) that dynamically builds a graph structure promoting the positive knowledge transfer when learning new tasks. In addition, we propose a Dynamic Expansion Graph Adaptive Mechanism (DEGAM) that generates adaptive weights to regulate the graph structure, further improving the positive knowledge transfer effectiveness. Experimental results show that the proposed methodology performs better than other baselines in continual learning.
U2 - 10.1109/TPAMI.2025.3564188
DO - 10.1109/TPAMI.2025.3564188
M3 - Article
SN - 0162-8828
SP - 1
EP - 18
JO - IEEE Transactions on Pattern Analysis and Machine Intelligence
JF - IEEE Transactions on Pattern Analysis and Machine Intelligence
ER -