  Abstractive summarization aims to generate a shorter version of the document
covering all the salient points in a compact and coherent fashion. On the other
hand, query-based summarization highlights those points that are relevant in
the context of a given query. The encode-attend-decode paradigm has achieved
notable success in machine translation, extractive summarization, dialog
systems, etc. But it suffers from the drawback of generation of repeated
phrases. In this work we propose a model for the query-based summarization task
based on the encode-attend-decode paradigm with two key additions (i) a query
attention model (in addition to document attention model) which learns to focus
on different portions of the query at different time steps (instead of using a
static representation for the query) and (ii) a new diversity based attention
model which aims to alleviate the problem of repeating phrases in the summary.
In order to enable the testing of this model we introduce a new query-based
summarization dataset building on debatepedia. Our experiments show that with
these two additions the proposed model clearly outperforms vanilla
encode-attend-decode models with a gain of 28% (absolute) in ROUGE-L scores.
