Network embedding has gained more attentions in recent years. It has been shown that the learned low-dimensional node vector representations could advance a myriad of graph mining tasks such as node classification, community detection, and link prediction. A vast majority of the existing efforts are overwhelmingly devoted to single-layered networks or homogeneous networks with a single type of nodes and node interactions. However, in many real-world applications, a variety of networks could be abstracted and presented in a multilayered fashion. Typical multi-layered networks include critical infrastructure systems, collaboration platforms, social recommender systems, to name a few. Despite the widespread use of multi-layered networks, it remains a daunting task to learn vector representations of different types of nodes due to the bewildering combination of both within-layer connections and cross-layer network dependencies. In this paper, we study a novel problem of multi-layered network embedding. In particular, we propose a principled framework – MANE to model both within-layer connections and cross-layer network dependencies simultaneously in a unified optimization framework for embedding representation learning. Experiments on real-world multi-layered networks corroborate the effectiveness of the proposed framework.
DESTINE: Dense Subgraph Detection on Multi-Layered Networks
Dense subgraph detection is a fundamental building block for a va- riety of applications. Most of the existing methods aim to discover dense subgraphs within either a single network or a multi-view network while ignoring the informative node dependencies across multiple layers of networks in a complex system. To date, it largely remains a daunting task to detect dense subgraphs on multi-layered networks. In this paper, we formulate the problem of dense sub- graph detection on multi-layered networks based on cross-layer consistency principle. We further propose a novel algorithm Des- tine based on projected gradient descent with the following ad- vantages. First, armed with the cross-layer dependencies, Destine is able to detect significantly more accurate and meaningful dense subgraphs at each layer. Second, it scales linearly w.r.t. the num- ber of links in the multi-layered network. Extensive experiments demonstrate the efficacy of the proposed Destine algorithm in various cases.
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- Destine: Dense Subgraph Detection on Multi-Layered Networks
- Page Range or eLocation-ID:
- 3558 to 3562
- Sponsoring Org:
- National Science Foundation
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