Covariance functions are the core of spatial statistics, stochastic processes, machine learning as well as many other theoretical and applied disciplines. The properties of the covariance function at small and large distances determine the geometric attributes of the associated Gaussian random field. Having covariance functions that allow to specify both local and global properties is certainly on demand. This paper provides a method to find new classes of covariance functions having such properties. We term these models hybrid as they are obtained as scale mixtures of piecewise covariance kernels against measures that are also defined as piecewise linear combination of parametric families of measures. In order to illustrate our methodology, we provide new families of covariance functions that are proved to be richer with respect to other well known families that have been proposed by earlier literature. More precisely, we derive a hybrid Cauchy-Matérn model, which allows us to index both long memory and mean square differentiability of the random field, and a hybrid Hole-Effect-Matérn model, which is capable of attaining negative values (hole effect), while preserving the local attributes of the traditional Matérn model. Our findings are illustrated through numerical studies with both simulated and real data.
La digitalización de procesos empresariales y el acceso a internet de un mayor número de personas genera un ambiente de incertidumbre. Por tal motivo el estudio tuvo como objetivo analizar el uso de plataformas digitales en la PYMES del cantón Azogues como herramientas de sostenibilidad en tiempos de pandemia. Se empleó una metodología de tipo descriptiva, exploratoria, con un enfoque cuantitativo, no experimental, de corte transversal. La muestra estuvo conformada por 151 PYMES. Se obtuvo como resultado que existe una influencia de las plataformas digitales en el contexto de estudio, especialmente las orientadas a generar espacios de comunicación entre el cliente y la empresa. Concluyendo que las plataformas de redes sociales son las preferidas por las empresas para explorar los beneficios de la digitalización, mientras tanto, la carencia de conocimiento en temas tecnológicos se convierte en una barrera de entrada a la transformación digital
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