MOX Report on Weighted functional data analysis for the calibration of ground motion models in Italy

A new MOX report entitled “Weighted functional data analysis for the calibration of ground motion models in Italy” by Bortolotti, T; Peli, R.; Lanzano, G; Sgobba, S.; Menafoglio, A has appeared in the MOX Report Collection.

The report can be donwloaded at the following link:

https://www.mate.polimi.it/biblioteca/add/qmox/31/2022.pdf

Abstract: Motivated by the crucial implications of Ground Motion Models (GMM) in terms of seismic hazard analysis and civil protection planning, this work extends a scalar ground motion model for Italy to the framework of Functional Data Analysis. The inherent characteristic of seismic data to be incomplete over the observation domain entails embedding the analysis in the context of partially observed functional data. This work proposes a novel methodology that combines pre-existing techniques of data reconstruction with the definition of observation-specific functional weights, which enter the estimation process to reduce the impact that the reconstructed parts of the curves have on the final estimates. The classical methods of smoothing and concurrent functional regression are extended to include weights. The advantages of the proposed methodology are assessed on synthetic data. Eventually, the weighted functional analysis performed on seismological da! ta is sho wn to provide a natural smoothing and stabilization of the spectral estimates of the GMM.