AUTHOR=Ferrone Lorenzo , Zanzotto Fabio Massimo TITLE=Symbolic, Distributed, and Distributional Representations for Natural Language Processing in the Era of Deep Learning: A Survey JOURNAL=Frontiers in Robotics and AI VOLUME=6 YEAR=2020 URL=https://www.frontiersin.org/journals/robotics-and-ai/articles/10.3389/frobt.2019.00153 DOI=10.3389/frobt.2019.00153 ISSN=2296-9144 ABSTRACT=

Natural language is inherently a discrete symbolic representation of human knowledge. Recent advances in machine learning (ML) and in natural language processing (NLP) seem to contradict the above intuition: discrete symbols are fading away, erased by vectors or tensors called distributed and distributional representations. However, there is a strict link between distributed/distributional representations and discrete symbols, being the first an approximation of the second. A clearer understanding of the strict link between distributed/distributional representations and symbols may certainly lead to radically new deep learning networks. In this paper we make a survey that aims to renew the link between symbolic representations and distributed/distributional representations. This is the right time to revitalize the area of interpreting how discrete symbols are represented inside neural networks.