Towards well-grounded phrase-level polarity analysis

Abstract

We propose a new rule-based system for phrase-level polarity analysis and show how it benefits from empirically validating its polarity composition through surveys with human subjects. The system's two-layer architecture and its underlying structure, i.e. its composition model, are presented. Two functions for polarity aggregation are introduced that operate on newly defined semantic categories. These categories detach a word's syntactic from its semantic behavior. An experimental setup is described that we use to carry out a thorough evaluation. It incorporates a newly created German-language data set that is made freely and publicly available. This data set contains polarity annotations at word-level, phrase-level and sentence-level and facilitates comparability between different studies and reproducibility of our results. © 2011 Springer-Verlag.