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20122026
most citedClustering and Community Detection in Directed Networks: A Survey

599 citations · 1.2k across the 114 of their papers we have counts for

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Showing 2019Show all

14 papers · 1 filter

cs.CL2019

An Ensemble Method for Producing Word Representations focusing on the Greek Language

Michalis Lioudakis, Stamatis Outsios, Michalis Vazirgiannis

In this paper we present a new ensemble method, Continuous Bag-of-Skip-grams (CBOS), that produces high-quality word representations putting emphasis on the modern Greek language.…

cs.LG2019★ 22 cited

Keep It Simple: Graph Autoencoders Without Graph Convolutional Networks

Guillaume Salha, Romain Hennequin, Michalis Vazirgiannis

Graph autoencoders (AE) and variational autoencoders (VAE) recently emerged as powerful node embedding methods, with promising performances on challenging tasks such as link predic…

cs.CL2019★ 5 cited

Bidirectional Context-Aware Hierarchical Attention Network for Document Understanding

Jean-Baptiste Remy, Antoine Jean-Pierre Tixier, Michalis Vazirgiannis

The Hierarchical Attention Network (HAN) has made great strides, but it suffers a major limitation: at level 1, each sentence is encoded in complete isolation. In this work, we pro…

cs.DS2019

Revisiting the Graph Isomorphism Problem with Semidefinite Programming

Giannis Nikolentzos, Michalis Vazirgiannis

It is well-known that the graph isomorphism problem can be posed as an equivalent problem of determining whether an auxiliary graph structure contains a clique of specific order. H…

cs.CL2019

Message Passing Attention Networks for Document Understanding

Giannis Nikolentzos, Antoine J. -P. Tixier, Michalis Vazirgiannis

Graph neural networks have recently emerged as a very effective framework for processing graph-structured data. These models have achieved state-of-the-art performance in many task…

stat.ML2019

k-hop Graph Neural Networks

Giannis Nikolentzos, George Dasoulas, Michalis Vazirgiannis

Graph neural networks (GNNs) have emerged recently as a powerful architecture for learning node and graph representations. Standard GNNs have the same expressive power as the Weisf…

cs.LG2019

Gravity-Inspired Graph Autoencoders for Directed Link Prediction

Guillaume Salha, Stratis Limnios, Romain Hennequin +2

Graph autoencoders (AE) and variational autoencoders (VAE) recently emerged as powerful node embedding methods. In particular, graph AE and VAE were successfully leveraged to tackl…

cs.LG2019★ 1 cited

Randomised Bayesian Least-Squares Policy Iteration

Nikolaos Tziortziotis, Christos Dimitrakakis, Michalis Vazirgiannis

We introduce Bayesian least-squares policy iteration (BLSPI), an off-policy, model-free, policy iteration algorithm that uses the Bayesian least-squares temporal-difference (BLSTD)…

stat.ML2019★ 90 cited

Graph Kernels: A Survey

Giannis Nikolentzos, Giannis Siglidis, Michalis Vazirgiannis

Graph kernels have attracted a lot of attention during the last decade, and have evolved into a rapidly developing branch of learning on structured data. During the past 20 years,…

cs.CL2019★ 6 cited

Energy-based Self-attentive Learning of Abstractive Communities for Spoken Language Understanding

Guokan Shang, Antoine Jean-Pierre Tixier, Michalis Vazirgiannis +1

Abstractive community detection is an important spoken language understanding task, whose goal is to group utterances in a conversation according to whether they can be jointly sum…

cs.SI2019

Multi-task Learning for Influence Estimation and Maximization

George Panagopoulos, Fragkiskos D. Malliaros, Michalis Vazirgiannis

We address the problem of influence maximization when the social network is accompanied by diffusion cascades. In prior works, such information is used to compute influence probabi…

cs.CL2019★ 5 cited

Evaluation of Greek Word Embeddings

Stamatis Outsios, Christos Karatsalos, Konstantinos Skianis +1

Since word embeddings have been the most popular input for many NLP tasks, evaluating their quality is of critical importance. Most research efforts are focusing on English word em…

cs.LG2019★ 31 cited

Rep the Set: Neural Networks for Learning Set Representations

Konstantinos Skianis, Giannis Nikolentzos, Stratis Limnios +1

In several domains, data objects can be decomposed into sets of simpler objects. It is then natural to represent each object as the set of its components or parts. Many conventiona…

cs.LG2019

A Degeneracy Framework for Scalable Graph Autoencoders

Guillaume Salha, Romain Hennequin, Viet Anh Tran +1

In this paper, we present a general framework to scale graph autoencoders (AE) and graph variational autoencoders (VAE). This framework leverages graph degeneracy concepts to train…