Leveraging LLMs for Explainable Recommender Systems: Exploring User Perceptions and Faithfulness in Generated Explanations

  • Itallo de Sousa Silva UFCG

Resumo


Sistemas de Recomendação (SRs) são amplamente utilizados para auxiliar usuários na descoberta de itens relevantes, mas sua complexidade levanta preocupações quanto à transparência e interpretabilidade. Este trabalho investiga o uso de Modelos de Linguagem de Grande Escala (LLMs) para gerar explicações automatizadas e centradas no usuário em SRs, avaliando também se tais explicações são fiéis ao processo decisório dos modelos. Inicialmente, conduzimos um estudo com usuários para avaliar recomendações e explicações personalizadas de filmes geradas pelo GPT-3.5 Turbo, mensurando percepção de efetividade, personalização e persuasão. Em seguida, analisamos a fidelidade das explicações nos domínios de filmes, músicas e livros utilizando quatro LLMs (GPT-4o, Llama3, Gemma2 e Mixtral 8x7B). Os resultados indicam que recomendações geradas por LLMs aumentam a satisfação dos usuários em comparação a recomendações aleatórias; entretanto, as explicações frequentemente não refletem adequadamente os fatores que influenciaram a recomendação. Além disso, explicações baseadas em preferências do usuário não foram consistentemente percebidas como superiores às genéricas.

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Publicado
19/10/2026
SILVA, Itallo de Sousa. Leveraging LLMs for Explainable Recommender Systems: Exploring User Perceptions and Faithfulness in Generated Explanations. In: CONCURSO DE TESES E DISSERTAÇÕES EM INTELIGÊNCIA ARTIFICIAL E COMPUTACIONAL (CTDIAC), 15. , 2026, Cuiabá/MT. Anais [...]. Porto Alegre: Sociedade Brasileira de Computação, 2026 . p. 37-51. DOI: https://doi.org/10.5753/ctdiac.2026.32877.