Quantizing rare random maps: application to flooding visualization - FAYOL / DEMO : Décision en Entreprise : Modélisation, Optimisation Access content directly
Journal Articles Journal of Computational and Graphical Statistics Year : 2023

Quantizing rare random maps: application to flooding visualization


Visualization is an essential operation when assessing the risk of rare events such as coastal or river floodings. The goal is to display a few prototype events that best represent the probability law of the observed phenomenon, a task known as quantization. It becomes a challenge when data is expensive to generate and critical events are scarce, like extreme natural hazard. In the case of floodings, each event relies on an expensive-to-evaluate hydraulic simulator which takes as inputs offshore meteo-oceanic conditions and dyke breach parameters to compute the water level map. In this article, Lloyd's algorithm, which classically serves to quantize data, is adapted to the context of rare and costly-to-observe events. Low probability is treated through importance sampling, while Functional Principal Component Analysis combined with a Gaussian process deal with the costly hydraulic simulations. The calculated prototype maps represent the probability distribution of the flooding events in a minimal expected distance sense, and each is associated to a probability mass. The method is first validated using a 2D analytical model and then applied to a real coastal flooding scenario. The two sources of error, the metamodel and the importance sampling, are evaluated to quantify the precision of the method.
Embargoed file
Embargoed file
1 10 5
Year Month Jours
Avant la publication
Wednesday, January 7, 2026
Embargoed file
Wednesday, January 7, 2026
Please log in to request access to the document

Dates and versions

hal-03752365 , version 1 (14-11-2023)


Attribution - NonCommercial - NoDerivatives



Charlie Sire, Rodolphe Le Riche, Didier Rullière, Jérémy Rohmer, Lucie Pheulpin, et al.. Quantizing rare random maps: application to flooding visualization. Journal of Computational and Graphical Statistics, 2023, 32 (4), pp.1556-1571. ⟨10.1080/10618600.2023.2203764⟩. ⟨hal-03752365⟩
235 View
2 Download



Gmail Facebook X LinkedIn More