' In this paper we introduce the task of misflagged duplicate question detection for question pairs in community question-answer (cQA) archives and compare it to the more standard task of detecting valid duplicate questions. A misflagged duplicate is a question that has been erroneously hand-flagged by the community as a duplicate of an archived one, where the two questions are not actually the same. We find that form is flagged duplicate detection, meta data features that capture user authority, question quality, and relational data between questions, outperform pure text-based methods, while for regular duplicate detection a combination of meta data features and semantic features gives the best results. We show that misflagged duplicate questions are even more challenging to model than regular duplicate question detection, but that good results can still be obtained.’