Dimitris Pappas

Education

• 

  Athens University of Economics and Business

  2013 - 2015

  Master's Degree Information Systems

  Activities and Societies: NLP , Sentiment Analysis

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  University of Crete

  2007 - 2013

  Bachelor's Degree Computer Science
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  Athens University of Economics and Business

  2015 - 2023

  Doctor of Philosophy - PhD Computer Science

  The thesis proposes new deep learning models and methodologies for biomedical Information Retrieval and Question Answering. The first part of the thesis focuses on retrieving abstracts of scientific literature given a natural language question submitted by a biomedical expert. Multiple state-of-the-art deep-learning models for biomedical document retrieval and snippet extraction are proposed. Joint models that simultaneously retrieve documents and snippets are also proposed. The second part of… Show more The thesis proposes new deep learning models and methodologies for biomedical Information Retrieval and Question Answering. The first part of the thesis focuses on retrieving abstracts of scientific literature given a natural language question submitted by a biomedical expert. Multiple state-of-the-art deep-learning models for biomedical document retrieval and snippet extraction are proposed. Joint models that simultaneously retrieve documents and snippets are also proposed. The second part of the thesis develops two new artificial datasets for biomedical cloze-style QA to address the scarcity of human-annotated data. The third part of the thesis trains deep learning models for factoid QA in two well-established biomedical datasets and examines six techniques for offline data augmentation. The best deep learning model was made publicly available as a research prototype during the Coronavirus pandemic to aid researchers around the world. Show less