Multiple Kernel Representation Learning on Networks
This work addresses the need for efficient and expressive node embedding methods in network analysis, though it is incremental as it builds on existing techniques.
The paper tackles the problem of learning node representations in networks by combining matrix factorization and random walk-based models, resulting in a weighted matrix factorization approach that outperforms baseline algorithms in downstream tasks like link prediction and node classification.
Learning representations of nodes in a low dimensional space is a crucial task with numerous interesting applications in network analysis, including link prediction, node classification, and visualization. Two popular approaches for this problem are matrix factorization and random walk-based models. In this paper, we aim to bring together the best of both worlds, towards learning node representations. In particular, we propose a weighted matrix factorization model that encodes random walk-based information about nodes of the network. The benefit of this novel formulation is that it enables us to utilize kernel functions without realizing the exact proximity matrix so that it enhances the expressiveness of existing matrix decomposition methods with kernels and alleviates their computational complexities. We extend the approach with a multiple kernel learning formulation that provides the flexibility of learning the kernel as the linear combination of a dictionary of kernels in data-driven fashion. We perform an empirical evaluation on real-world networks, showing that the proposed model outperforms baseline node embedding algorithms in downstream machine learning tasks.