Utilizing passages in fusion-based document retrieval

The usage of passage-level information has been successfully demonstrated in many core IR tasks, and among such tasks, the task of passage-based document retrieval. In this work, we study the merits of utilizing similar information for the fusion-based document retrieval task.Overall,we showthat such information can be highly useful for this task as well. To this end, we propose three passagebased fusion methods and show that their performance can transcend that of strong document-level fusion methods.