The consistency of a user's sentiment regarding a target's stance on an issue is not a property of a single document, and it depends on the label for each document that mentions the targetissue pair in question.
this property is not appropriately expressed as an SVM feature; instead, we incorporate Hypothesis 3 as follows: we cluster the documents authored by the same user and target (for tweets) or the same user, target, and issue (for forum posts) into one cluster.