Combining Embeddings and Domain Knowledge for Job Posting Duplicate Detection
Matthias Engelbach, Dennis Klau, Maximilien Kintz, Alexander Ulrich
TL;DR
This work tackles the practical problem of detecting duplicate job postings across multiple sources by blending overlap-based text similarity, semantic embeddings, and domain-knowledge weighted keyword matching. The proposed multi-component pipeline, with data preprocessing and a final Total Score TS, significantly improves precision-recall balance and achieves an $F1$ of $0.94$ on validation, enabling productive deployment in a real-world recruitment setting. Key contributions include a robust integration of text overlap with skill-focused measures, a dynamic weighting scheme for skills, and a production-ready deployment that demonstrates scalability and real-user benefit. The results highlight the value of combining traditional text matching with domain-specific knowledge, while outlining avenues for future enhancements such as larger-scale evaluation and optional usage of large language models for scoring.
Abstract
Job descriptions are posted on many online channels, including company websites, job boards or social media platforms. These descriptions are usually published with varying text for the same job, due to the requirements of each platform or to target different audiences. However, for the purpose of automated recruitment and assistance of people working with these texts, it is helpful to aggregate job postings across platforms and thus detect duplicate descriptions that refer to the same job. In this work, we propose an approach for detecting duplicates in job descriptions. We show that combining overlap-based character similarity with text embedding and keyword matching methods lead to convincing results. In particular, we show that although no approach individually achieves satisfying performance, a combination of string comparison, deep textual embeddings, and the use of curated weighted lookup lists for specific skills leads to a significant boost in overall performance. A tool based on our approach is being used in production and feedback from real-life use confirms our evaluation.
