KnowMe-Bench: Benchmarking Person Understanding for Lifelong Digital Companions
Tingyu Wu, Zhisheng Chen, Ziyan Weng, Shuhe Wang, Chenglong Li, Shuo Zhang, Sen Hu, Silin Wu, Qizhen Lan, Huacan Wang, Ronghao Chen
TL;DR
KnowMe-Bench shifts the evaluation of lifelong digital companions from retrieval accuracy to evidence-grounded person understanding by using high-density autobiographical narratives and a flashback-aware, time-aligned lifelog representation. It introduces a four-stage data pipeline (Segmentation, ANU Extraction, Temporal Realignment, Narrative Instantiation) and a three-tier evaluation (Memory, Reasoning, Insight) with an LLM-as-a-Judge scoring protocol and expert verification. Experiments across three public corpora reveal that retrieval-based systems improve factual recall but struggle with temporally grounded explanations and high-level psychodynamic reasoning, highlighting a gap in current memory architectures. The work provides openly available data, timelines, baselines, and evaluation tools to advance truly understanding user motivations, values, and long-horizon preferences in digital companions.
Abstract
Existing long-horizon memory benchmarks mostly use multi-turn dialogues or synthetic user histories, which makes retrieval performance an imperfect proxy for person understanding. We present \BenchName, a publicly releasable benchmark built from long-form autobiographical narratives, where actions, context, and inner thoughts provide dense evidence for inferring stable motivations and decision principles. \BenchName~reconstructs each narrative into a flashback-aware, time-anchored stream and evaluates models with evidence-linked questions spanning factual recall, subjective state attribution, and principle-level reasoning. Across diverse narrative sources, retrieval-augmented systems mainly improve factual accuracy, while errors persist on temporally grounded explanations and higher-level inferences, highlighting the need for memory mechanisms beyond retrieval. Our data is in \href{KnowMeBench}{https://github.com/QuantaAlpha/KnowMeBench}.
