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arXiv · 2306.08947

RecFusion: A Binomial Diffusion Process for 1D Data for Recommendation

Gabriel Bénédict·Olivier Jeunen·Samuele Papa·Samarth Bhargav·Daan Odijk·Maarten de Rijke
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Abstract

In this paper we propose RecFusion, which comprise a set of diffusion models for recommendation. Unlike image data which contain spatial correlations, a user-item interaction matrix, commonly utilized in recommendation, lacks spatial relationships between users and items. We formulate diffusion on a 1D vector and propose binomial diffusion, which explicitly models binary user-item interactions with a Bernoulli process. We show that RecFusion approaches the performance of complex VAE baselines on the core recommendation setting (top-n recommendation for binary non-sequential feedback) and the most common datasets (MovieLens and Netflix). Our proposed diffusion models that are specialized for 1D and/or binary setups have implications beyond recommendation systems, such as in the medical domain with MRI and CT scans.

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Gabriel Bénédict, Olivier Jeunen, Samuele Papa, Samarth Bhargav, Daan Odijk, Maarten de Rijke. 2023-06-15. RecFusion: A Binomial Diffusion Process for 1D Data for Recommendation. https://arxiv.org/abs/2306.08947

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