Eirini Papagiannopoulou


2021

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Keyword Extraction Using Unsupervised Learning on the Document’s Adjacency Matrix
Eirini Papagiannopoulou | Grigorios Tsoumakas | Apostolos Papadopoulos
Proceedings of the Fifteenth Workshop on Graph-Based Methods for Natural Language Processing (TextGraphs-15)

This work revisits the information given by the graph-of-words and its typical utilization through graph-based ranking approaches in the context of keyword extraction. Recent, well-known graph-based approaches typically employ the knowledge from word vector representations during the ranking process via popular centrality measures (e.g., PageRank) without giving the primary role to vectors’ distribution. We consider the adjacency matrix that corresponds to the graph-of-words of a target text document as the vector representation of its vocabulary. We propose the distribution-based modeling of this adjacency matrix using unsupervised (learning) algorithms. The efficacy of the distribution-based modeling approaches compared to state-of-the-art graph-based methods is confirmed by an extensive experimental study according to the F1 score. Our code is available on GitHub.

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Keyphrase Extraction from Scientific Articles via Extractive Summarization
Chrysovalantis Giorgos Kontoulis | Eirini Papagiannopoulou | Grigorios Tsoumakas
Proceedings of the Second Workshop on Scholarly Document Processing

Automatically extracting keyphrases from scholarly documents leads to a valuable concise representation that humans can understand and machines can process for tasks, such as information retrieval, article clustering and article classification. This paper is concerned with the parts of a scientific article that should be given as input to keyphrase extraction methods. Recent deep learning methods take titles and abstracts as input due to the increased computational complexity in processing long sequences, whereas traditional approaches can also work with full-texts. Titles and abstracts are dense in keyphrases, but often miss important aspects of the articles, while full-texts on the other hand are richer in keyphrases but much noisier. To address this trade-off, we propose the use of extractive summarization models on the full-texts of scholarly documents. Our empirical study on 3 article collections using 3 keyphrase extraction methods shows promising results.

2016

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Large-Scale Semantic Indexing and Question Answering in Biomedicine
Eirini Papagiannopoulou | Yiannis Papanikolaou | Dimitris Dimitriadis | Sakis Lagopoulos | Grigorios Tsoumakas | Manos Laliotis | Nikos Markantonatos | Ioannis Vlahavas
Proceedings of the Fourth BioASQ workshop