Data-Faithful Natural Language Generation for Explaining Fitness-Market Anomalies

  • Kauan Divino Pouso Mariano UFG
  • Fabrycio Leite Nakano Almada UFG
  • Victor Emanuel da Silva Monteiro UFG
  • Maykon Adriell Dutra UFG
  • Jefferson Felex de Faria PUC-Goiás
  • Jennifer Vitória da Silva Peixoto PUC-Goiás
  • Kamylla Sejane Pouso Freitas Alfredo Nasser University Center

Resumo


This study presents an integrated pipeline that transforms anomaly-detection outputs from global fitness-market data into data-faithful narratives. Using a 132-country panel and a 2019 baseline, we analyze observed post-COVID-19 recovery through 2025, while treating 2026 only as a modelled extension. Four complementary detectors—regional-median deviations, linear-regression residuals, Random Forest residuals, and Isolation Forest—are combined through method agreement and mapped to a rule-based typology. A deterministic, template-based Natural Language Generation (NLG) component then produces short, medium, and complete explanations from tabular evidence. In 2025, 14 countries were consensus anomalies; Guyana exemplified market growth without participatory expansion, with revenue recovery of +401.43%, participation recovery of -2.06%, and a 403.50-point gap. All 132 narratives passed automatic factual-consistency checks. These checks validate field preservation rather than fluency, usefulness, or explanatory quality; human evaluation remains future work.

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Publicado
19/10/2026
MARIANO, Kauan Divino Pouso; ALMADA, Fabrycio Leite Nakano; MONTEIRO, Victor Emanuel da Silva; DUTRA, Maykon Adriell; FARIA, Jefferson Felex de; PEIXOTO, Jennifer Vitória da Silva; FREITAS, Kamylla Sejane Pouso. Data-Faithful Natural Language Generation for Explaining Fitness-Market Anomalies. In: SIMPÓSIO BRASILEIRO DE TECNOLOGIA DA INFORMAÇÃO E DA LINGUAGEM HUMANA (STIL), 17. , 2026, Cuiabá/MT. Anais [...]. Porto Alegre: Sociedade Brasileira de Computação, 2026 . p. 567-572. DOI: https://doi.org/10.5753/stil.2026.29472.