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arXiv · 1907.08793

Improving Skip-Gram based Graph Embeddings via Centrality-Weighted Sampling

Pedro Almagro-Blanco·Fernando Sancho-Caparrini
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Abstract

Network embedding techniques inspired by word2vec represent an effective unsupervised relational learning model. Commonly, by means of a Skip-Gram procedure, these techniques learn low dimensional vector representations of the nodes in a graph by sampling node-context examples. Although many ways of sampling the context of a node have been proposed, the effects of the way a node is chosen have not been analyzed in depth. To fill this gap, we have re-implemented the main four word2vec inspired graph embedding techniques under the same framework and analyzed how different sampling distributions affects embeddings performance when tested in node classification problems. We present a set of experiments on different well known real data sets that show how the use of popular centrality distributions in sampling leads to improvements, obtaining speeds of up to 2 times in learning times and increasing accuracy in all cases.

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Pedro Almagro-Blanco, Fernando Sancho-Caparrini. 2019-07-20. Improving Skip-Gram based Graph Embeddings via Centrality-Weighted Sampling. https://arxiv.org/abs/1907.08793

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