Simplifying words in context. Experiments with two lexical resources in Spanish

•We developed the first lexical simplification for Spanish.•Human-informed evaluation of the system.•Comparison of two WSD strategies.•Comparison of two lexical resources.•Software and dataset made available for testing and verification.

In this paper we study the effect of different lexical resources for selecting synonyms and strategies for word sense disambiguation in a lexical simplification system for the Spanish language. The resources used for the experiments are the Spanish EuroWordNet, the Spanish Open Thesaurus and a combination of both. As for the synonym selection strategies, we have used both local and global contexts for word sense disambiguation. We present a novel evaluation framework in lexical simplification that takes into account the level of ambiguity of the word to be simplified. The evaluation compares various instances of the lexical simplification system, a gold standard, and a baseline. The paper presents an in-depth qualitative error analysis of the results.