DRUM: Learning Demonstration Retriever for Large MUlti-modal Models

Abstract

Recently, large language models (LLMs) have demonstrated impressive capabilities in dealing with new tasks with the help of in-context learning (ICL). In the study of Large Vision-Language Models (LVLMs), when implementing ICL, researchers usually adopt the naive strategies like fixed demonstrations across different samples, or selecting demonstrations directly via a visual-language embedding model. These methods do not guarantee the configured demonstrations fit the need of the LVLMs. To address this issue, we propose a novel framework, demonstration retriever for large multimodal model (DRUM), which fine-tunes the CLIP embedding model to better meet the LVLM’s needs. First, we discuss the retrieval strategies for a visual-language task, assuming an embedding model is given. And we propose to concate the image and text embeddings to enhance the retrieval performance. Second, we propose to re-rank the the embedding model’s retrieved demonstrations via the LVLM’s feedbacks, and calculate a list-wise ranking loss for training the embedding model. Third, we propose an iterative demonstration mining strategy to improve the training of the embedding model. Through extensive experiments on 3 types of visual-language tasks, 7 benchmark datasets, our DRUM framework is proven to be effective in boosting the LVLM’s in-context learning performance via retrieving more proper demonstrations.