Causal Intersectionality and Dual Form of Gradient Descent for Multimodal Analysis: a Case Study on Hateful Memes

Abstract

In the wake of the explosive growth of machine learning (ML) usage, particularly within the context of emerging Large Language Models (LLMs), comprehending the semantic significance rooted in their internal workings is crucial. While causal analyses focus on defining semantics and its quantification, the gradient-based approach is central to explainable AI (XAI), tackling the interpretation of the black box. By synergizing these approaches, the exploration of how a model's internal mechanisms illuminate its causal effect has become integral for evidence-based decision-making. A parallel line of research has revealed that intersectionality - the combinatory impact of multiple demographics of an individual - can be structured in the form of an Averaged Treatment Effect (ATE). Initially, this study illustrates that the hateful memes detection problem can be formulated as an ATE, assisted by the principles of intersectionality, and that a modality-wise summarization of gradient-based attention attribution scores can delineate the distinct behaviors of three Transformerbased models concerning ATE. Subsequently, we show that the latest LLM LLaMA2 has the ability to disentangle the intersectional nature of memes detection in an in-context learning setting, with their mechanistic properties elucidated via meta-gradient, a secondary form of gradient. In conclusion, this research contributes to the ongoing dialogue surrounding XAI and the multifaceted nature of ML models