  Conversational search provides a natural interface for information retrieval
(IR). Recent approaches have demonstrated promising results in applying dense
retrieval to conversational IR. However, training dense retrievers requires
large amounts of in-domain paired data. This hinders the development of
conversational dense retrievers, as abundant in-domain conversations are
expensive to collect. In this paper, we propose CONVERSER, a framework for
training conversational dense retrievers with at most 6 examples of in-domain
dialogues. Specifically, we utilize the in-context learning capability of large
language models to generate conversational queries given a passage in the
retrieval corpus. Experimental results on conversational retrieval benchmarks
OR-QuAC and TREC CAsT 19 show that the proposed CONVERSER achieves comparable
performance to fully-supervised models, demonstrating the effectiveness of our
proposed framework in few-shot conversational dense retrieval. All source code
and generated datasets are available at https://github.com/MiuLab/CONVERSER
