8 citations · 9 across the 4 of their papers we have counts for
6 papers · 1 filter
The Gauss Hypergeometric Covariance Kernel for Modeling Second-Order Stationary Random Fields in Euclidean Spaces: its Compact Support, Properties and Spectral Representation
Xavier Emery, Alfredo Alegría
This paper presents a parametric family of compactly-supported positive semidefinite kernels aimed to model the covariance structure of second-order stationary isotropic random fie…
Karhunen-Loève Expansions for Axially Symmetric Gaussian Processes: Modeling Strategies and Approximations
Alfredo Alegría, Francisco Cuevas-Pacheco
Axially symmetric processes on spheres, for which the second-order dependency structure may substantially vary with shifts in latitude, are a prominent alternative to model the spa…
The Turning Arcs: a Computationally Efficient Algorithm to Simulate Isotropic Vector-Valued Gaussian Random Fields on the -Sphere
Alfredo Alegría, Xavier Emery, Christian Lantuéjoul
Random fields on the sphere play a fundamental role in the natural sciences. This paper presents a simulation algorithm parenthetical to the spectral turning bands method used in E…
Modelling and simulation of multifractal star-shaped particles
Alfredo Alegría
The problem of constructing flexible stochastic models to describe the variability in shape of solid particles is challenging. Natural objects often exhibit mono- or multi-fractal…
Modeling Temporally Evolving and Spatially Globally Dependent Data
Emilio Porcu, Alfredo Alegría, Reinhard Furrer
The last decades have seen an unprecedented increase in the availability of data sets that are inherently global and temporally evolving, from remotely sensed networks to climate m…
Asymmetric Matrix-Valued Covariances for Multivariate Random Fields on Spheres
Alfredo Alegría, Emilio Porcu, Reinhard Furrer
Matrix-valued covariance functions are crucial to geostatistical modeling of multivariate spatial data. The classical assumption of symmetry of a multivariate covariance function i…