Concept maps can be used to concisely represent important information and
bring structure into large document collections. Therefore, we study a variant
of multi-document summarization that produces summaries in the form of concept
maps. However, suitable evaluation datasets for this task are currently
missing. To close this gap, we present a newly created corpus of concept maps
that summarize heterogeneous collections of web documents on educational
topics. It was created using a novel crowdsourcing approach that allows us to
efficiently determine important elements in large document collections. We
release the corpus along with a baseline system and proposed evaluation
protocol to enable further research on this variant of summarization.Comment: Published at EMNLP 201