Synthetic Multimodal Question Generation
Ian Wu, Sravan Jayanthi, Vijay Viswanathan, Simon Rosenberg, Sina Pakazad, Tongshuang Wu, Graham Neubig
TL;DR
The paper tackles the difficulty of evaluating multimodal retrieval-augmented QA (MMRAG) by introducing SMMQG, a synthetic data framework that generates question-and-answer pairs grounded in multimodal documents with fine-grained control over question styles and modalities. It leverages a retriever, an LLM, and an LMM in a closed loop to produce 1024 QA pairs from Wikipedia and demonstrates that the synthetic data yields actionable, style- and modality-specific insights into retriever and QA model performance. A human study shows SMMQG data quality is on par with crowdsourced MMQA, and concurrence analysis reveals strong alignment with MMQA in downstream evaluation. Collectively, SMMQG enables automatic, scalable, and tailored evaluation of MMRAG systems, supporting model selection and revealing weaknesses that fixed benchmarks might miss.
Abstract
Multimodal Retrieval Augmented Generation (MMRAG) is a powerful approach to question-answering over multimodal documents. A key challenge with evaluating MMRAG is the paucity of high-quality datasets matching the question styles and modalities of interest. In light of this, we propose SMMQG, a synthetic data generation framework. SMMQG leverages interplay between a retriever, large language model (LLM) and large multimodal model (LMM) to generate question and answer pairs directly from multimodal documents, with the questions conforming to specified styles and modalities. We use SMMQG to generate an MMRAG dataset of 1024 questions over Wikipedia documents and evaluate state-of-the-art models using it, revealing insights into model performance that are attainable only through style- and modality-specific evaluation data. Next, we measure the quality of data produced by SMMQG via a human study. We find that the quality of SMMQG-generated synthetic data is on par with the quality of the crowdsourced benchmark MMQA and that downstream evaluation results using both datasets strongly concur.
