Exploring the Synergy of Quantitative Factors and Newsflow Representations from Large Language Models for Stock Return Prediction
Tian Guo, Emmanuel Hauptmann
TL;DR
This work addresses stock return prediction by fusing quantitative factors with unstructured newsflow representations generated by large language models. It introduces a fusion learning framework that creates unified representations from factor and news modalities, and compares three fusion architectures, followed by a mixture model that adaptively combines factors-based and fusion-based predictions. To stabilize the training of the mixture, the authors propose a decoupled training scheme grounded in distribution matching via KL divergence between a trainable and a target mixture distribution, with theoretical support. Experiments across North American, Emerging Markets, and European universes show that simple fusion can outperform single-modality baselines, while the decoupled mixture yields robust performance across markets; fine-tuning the LLM has mixed effects depending on market efficiency. Overall, the paper provides practical guidance for multimodal modeling in finance, highlighting when to rely on fusion versus mixture methods and how to train them for stability and cross-market robustness.
Abstract
In quantitative investing, return prediction supports various tasks, including stock selection, portfolio optimization, and risk management. Quantitative factors, such as valuation, quality, and growth, capture various characteristics of stocks. Unstructured data, like news and transcripts, has attracted growing attention, driven by recent advances in large language models (LLMs). This paper examines effective methods for leveraging multimodal factors and newsflow in return prediction and stock selection. First, we introduce a fusion learning framework to learn a unified representation from factors and newsflow representations generated by an LLM. Within this framework, we compare three methods of different architectural complexities: representation combination, representation summation, and attentive representations. Next, building on the limitation of fusion learning observed in empirical comparison, we explore the mixture model that adaptively combines predictions made by single modalities and their fusion. To mitigate the training instability of the mixture model, we introduce a decoupled training approach with theoretical insights. Finally, our experiments on real investment universes yield several insights into effective multimodal modeling of factors and news for stock return prediction and selection.
