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Exploring syntactical features for anomaly detection in application logs

Rafael Copstein, Egil Karlsen, Jeff Schwartzentruber, Nur Zincir-Heywood and Malcolm Heywood


In this research, we analyze the effect of lightweight syntactical feature extraction techniques from the field of information retrieval for log abstraction in information security. To this end, we evaluate three feature extraction techniques and three clustering algorithms on four different security datasets for anomaly detection. Results demonstrate that these techniques have a role to play for log abstraction in the form of extracting syntactic features which improves the identification of anomalous minority classes, specifically in homogeneous security datasets.


Funding statement: This research was enabled by the support of the Natural Science and Engineering Research Council of Canada Alliance Grant and 2Keys Corporation.


The first author gratefully acknowledges the support by the province of Nova Scotia. The research is conducted as part of the Dalhousie NIMS Lab at:


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Received: 2021-11-27
Revised: 2022-02-16
Accepted: 2022-02-19
Published Online: 2022-03-23
Published in Print: 2022-04-26

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