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arXiv · 2609.14256

Document Topic Alignment Metrics for Evaluating Topic Models of Short-Text Public Health Communications on Social Media

Wangjiaxuan Xin·Shuhua Yin·Yaorong Ge·Shi Chen
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Abstract

Topic models are widely used to analyze public health-related social media short texts, yet their evaluation remains dominated by metrics that focus entirely on generated topics alone. There is a lack of metrics that quantitatively assess whether assigned topics meaningfully represent the corresponding short-text posts. We propose Document-Topic Alignment metrics (DoTA), an assignment-aware evaluation framework comprising metrics that measure semantic alignment between documents (posts) and their assigned topics. We also introduce margin-based and discriminative variants that capture topic assignment confidence and distinguishability. We evaluate DoTA across five topic models on three public health-related social media datasets from X and compare DoTA metrics with conventional topic-based metrics. Results show that DoTA provides complementary evaluation cues and aligns meaningfully with human evaluations. These findings establish the need for assignment-aware evaluation and demonstrate that the addition of DoTA enables a more comprehensive and practically meaningful evaluation for assessing short-text topic modeling performance.

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Wangjiaxuan Xin, Shuhua Yin, Yaorong Ge, Shi Chen. 2026-09-13. Document Topic Alignment Metrics for Evaluating Topic Models of Short-Text Public Health Communications on Social Media. https://arxiv.org/abs/2609.14256

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