arXiv Machine Learning By Zhengyu Fang, Liang Wang, Yingtong Dou, Yuzhong Chen, Shubham Jain, Junpeng Wang, Xiran Fan, Menghai Pan, Jiarui Sun, Yan Zheng, Yiwei Cai

PersonaAgent: Retrieval-Augmented Transaction Anomaly Scoring with Refreshable Multi-Entity Persona Memory

Read the original on arXiv Machine Learning →

PersonaAgent is a retrieval‑augmented transaction anomaly detection framework that stores the latest entity behavior signals as refreshable personas in memory. It updates these personas weekly via a batch job and, during inference, retrieves them with a lightweight adapter to augment a base anomaly classifier’s scoring. Benchmarks at Visa show that PersonaAgent can process 1,000 transactions in 1–2 ms while improving PR‑AUC by 0.65–6.58 % and production business metrics by 8.93–14.24 % relative to baseline models.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv Machine Learning.

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