FCC: Three Approaches for Semantic Textual Similarity

In this paper we describe the three approaches we submitted to the Semantic Textual Similarity task of SemEval 2012. The first approach considers to calculate the semantic similarity by using the Jaccard coefficient with term expansion using synonyms. The second approach uses the semantic similarity reported by Mihalcea in (Mihalcea et al., 2006). The third approach employs Random Indexing and Bag of Concepts based on context vectors. We consider that the first and third approaches obtained a comparable performance, meanwhile the second approach got a very poor behavior. The best ALL result was obtained with the third approach, with a Pearson correlation equal to 0.663.