DEESSE: entity-Driven Exploratory and sErendipitous Search SystEm.

We present DEESSE [1], a tool that enables an exploratory and serendipitous exploration - at entity level, of the content of two different social media: Wikipedia, a user-curated online encyclopedia, and Yahoo Answers, a more unconstrained question/answering forum. DEESSE represents the content of each source as an entity network, which is further enriched with metadata about sentiment, writing quality, and topical category. Given a query entity, entity results are retrieved from the network by employing an algorithm based on a random walk with restart to the query. Following the emerging paradigm of composite retrieval, we organize the results into topically coherent bundles instead of showing them in a simple ranked list.