  Entity resolution (ER) is an important data integration task with a wide
spectrum of applications. The state-of-the-art solutions on ER rely on
pre-trained language models (PLMs), which require fine-tuning on a lot of
labeled matching/non-matching entity pairs. Recently, large languages models
(LLMs), such as GPT-4, have shown the ability to perform many tasks without
tuning model parameters, which is known as in-context learning (ICL) that
facilitates effective learning from a few labeled input context demonstrations.
However, existing ICL approaches to ER typically necessitate providing a task
description and a set of demonstrations for each entity pair and thus have
limitations on the monetary cost of interfacing LLMs. To address the problem,
in this paper, we provide a comprehensive study to investigate how to develop a
cost-effective batch prompting approach to ER. We introduce a framework BATCHER
consisting of demonstration selection and question batching and explore
different design choices that support batch prompting for ER. We also devise a
covering-based demonstration selection strategy that achieves an effective
balance between matching accuracy and monetary cost. We conduct a thorough
evaluation to explore the design space and evaluate our proposed strategies.
Through extensive experiments, we find that batch prompting is very
cost-effective for ER, compared with not only PLM-based methods fine-tuned with
extensive labeled data but also LLM-based methods with manually designed
prompting. We also provide guidance for selecting appropriate design choices
for batch prompting.
