EGU25-8449, updated on 14 Mar 2025
https://doi.org/10.5194/egusphere-egu25-8449
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Poster | Tuesday, 29 Apr, 08:30–10:15 (CEST), Display time Tuesday, 29 Apr, 08:30–12:30
 
Hall X5, X5.6
The crossing-point quantile: an optimal point-forecast in terms of ROC areas. 
Zied Ben Bouallegue1 and Maxime Taillardat2,3
Zied Ben Bouallegue and Maxime Taillardat
  • 1ECMWF, Forecast Department , United Kingdom of Great Britain – England, Scotland, Wales (zied.benbouallegue@ecmwf.int)
  • 2Météo-France, Toulouse, France
  • 3CNRM, Université de Toulouse, Météo-France, CNRS, Toulouse, France

A point-forecast is defined as a single-value forecast expressed in the unit of a variable of interest. A deterministic forecast for 2m temperature at Vienna tomorrow is a point-forecast. Point-forecasts are required by some forecast users and for various applications. When an ensemble prediction system is at hand, a point-forecast can take the form of a distribution functional such as the ensemble mean or an ensemble quantile. In this context, we introduce a new type of point-forecast based on the concept of crossing-point forecast (Ben Bouallègue, 2021). We argue that this self-adaptive forecast should be better suited for some users than other point-forecasts. More precisely, we demonstrate that the so-called crossing-point quantile is an optimal forecast in terms of Pierce Skill Score (or equivalently in terms of area under the ROC curve) for any event of interest.  

Ben Bouallègue Z (2021), On the verification of the crossing-point forecast, Tellus A. DOI:10.1080/16000870.2021.1913007 

How to cite: Ben Bouallegue, Z. and Taillardat, M.: The crossing-point quantile: an optimal point-forecast in terms of ROC areas. , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8449, https://doi.org/10.5194/egusphere-egu25-8449, 2025.