cs.CLJul 5, 2025

POSID: Target-Task-Unsupervised Person-Attribute Extraction from Heterogeneous Public-Safety Text

Authors: KMA Solaiman

Organizations: Department of Computer Science, Purdue University, West Lafayette, IN, USA

Abstract

Person descriptions in public-safety text can be compact and regular, or distributed across heterogeneous narratives in which evidence boundaries and person ownership are ambiguous. We present POSID, a target-task-unsupervised framework that decomposes person-attribute extraction into candidate localization, provenance-controlled extraction scope, structured recovery and traversal, and person association, without supervised training or fine-tuning on the target task. We evaluate six localization configurations under two traversal policies across three real-use cohorts and two controlled synthetic diagnostics. On structurally regular descriptions, the strongest configurations reach 1.000/.972 Attr-Only (AO)/Attr-Value (AV) F1 on Compact500. Across the real-use cohorts, every RE-containing configuration benefits from conservative early stopping, while semantic-only retrieval can benefit from continued traversal when localization is less constrained. On the heterogeneous multi-person Challenge14 cohort, the best automatic AO and AV results are .500 and .382; replacing automatic candidates with verified evidence raises the frozen extractor to .522/.410 under early stopping, showing that localization is one of the material bottlenecks. We further introduce provenance-aware scoring for collective and underspecified evidence and a separate person-aware diagnostic for ownership and fragmentation. Together, the results establish a measurable operating regime for inspectable person-attribute extraction and distinguish errors due to localization, traversal, structured recovery, and attribution. Code: https://github.com/ksolaiman/hart-posid.

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