How can you spot fraud, a system failure, or unusual behavior when you don’t know in advance what you’re looking for? That is the whole point of anomaly detection, a key area of artificial intelligence used in robotics, finance, and healthcare.
To meet this challenge, researchers often combine multiple algorithms. One of the main obstacles is determining how to select these different algorithms to optimize results. A common strategy is to choose diverse algorithms that “think” differently. However, measuring algorithmic diversity remains a complex task.
The IRIT team (CNRS, UT, INPT, UT Capitole, UT2J) proposes an innovative approach: understanding how algorithms make their decisions, rather than simply accepting their results. Using explainability tools (known as SHAP), researchers analyze precisely which data elements influence each model. This allows them to compare algorithms not only based on their results, but also on how they “reason.”
This discovery makes it possible to better select and combine models to build artificial intelligence systems that are both more powerful and more reliable. But the researchers emphasize a key point: diversity alone is not enough. To be effective, each model must also perform well on its own.
Reference : Levy, J., Saves, P., Garouani, M., Verstaevel, N., Gaudou, B. (2026). Analyzing Shapley Additive Explanations to Understand Anomaly Detection Algorithm Behaviors and Their Complementarity. In: Baratchi, M., Nijssen, S., van Rijn, J.N. (eds) Advances in Intelligent Data Analysis XXIV. IDA 2026. Lecture Notes in Computer Science, vol 16513. Springer, Cham.
https://doi.org/10.1007/978-3-032-23833-7_10