“…Nevertheless, the real situations are: (1) there often exist many domains of comments in the meanwhile; and (2) there is an adequate amount of labeled training data for every domain of interest is typically impractical, which makes the further study on how to handle with the limited-resource multiple domains of data necessary and worthwhile. To this end, a series of powerful multi-task models, which consider the system learning for each domain as an independent task so that each task can reinforce and complement each other, is established [52,38,39,12,11,21,59,61,13,37,38,49,36,54]. Among them, a group of representative studies employ a shared-private model [37,52,38,39,12,11,21,59,61], which introduces two feature spaces for any task: one is used to store task-dependent features, the other is used to capture shared features.…”