Relational Features in Fine-Grained Opinion Analysis Richard Johansson author Alessandro Moschitti author 2013-09 text journal article Computational Linguistics continuing MIT Press Cambridge, MA periodical academic journal johansson-moschitti-2013-relational 10.1162/COLI_a_00141 https://aclanthology.org/J13-3002/ 2013-09 39 3 473 509