Abstract: As an emerging evaluation criteria of information retrieval(IR), readability plays an important role in accessing documents relevance, utility and quality. How to provide different users with relevant and readable documents has been an urgent problem in vertical search. In order to solve this problem, we propose a new ontology-based readability method. Based on users’ reading process, we measure documents readability from surface and conceptual levels. In this model, three readability indicator shave been introduced, i.e., Concept Topography, Concept Scope and Document Coherence. Specifically, the readability of a document that computed by individual or combined indicators can be used to re-rank the initial lists of documents which are returned by a conventional search engine. In medical domain, the user-oriented evaluations show that our model has good correlation with humans’ judgments in readability prediction. And our model is also competitive compared with one of the state-of-the-artreadability models in system-orient edevaluation.

Key words: readability, documents re-ranking, vertical search