Portrait de Richard Khoury

Richard Khoury

Membre affilié
Professeur agrégé, Université Laval, Département d'informatique et de génie logiciel
Sujets de recherche
Analyse de données
Modèles génératifs
Traitement du langage naturel

Publications

Causal Parametric Drift Simulation: A Digital Twin Framework for Classifier Robustness Evaluation
Julien Lafrance
Véronique Tremblay
Machine learning classifiers in dynamic environments face concept drift -- changes in the data-generating process that degrade performance. … (voir plus)Conventional evaluation via static test sets or noise perturbations fails to preserve causal dependencies in tabular data, often producing causally invalid assessments. Post-hoc tools like SHAP and LIME offer correlational insights that may not reflect the causal mechanisms driving model failure. We propose a framework that complements existing drift detection by leveraging Structural Causal Models as "Digital Twins" of data-generating processes, enabling precise causal interventions while preserving structural dependencies. Our technique, Causal Parametric Drift Simulation, stress-tests classifiers to identify vulnerabilities before deployment. Experiments on the Open Sourcing Mental Illness (OSMH) dataset demonstrate that this approach exposes latent vulnerabilities invisible to standard statistical monitors.
Neural Bandits for Data Mining: Searching for Dangerous Polypharmacy