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arXiv · 2309.11402

Spatio-Temporal Weighted Regression Model with Fractional-Colored Noise: Parameter estimation and consistency

Héctor Araya·Lisandro Fermín·Silfrido Gómez·Tania Roa·Soledad Torres
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Abstract

Geographical and Temporal Weighted Regression (GTWR) model is an important local technique for exploring spatial heterogeneity in data relationships, as well as temporal dependence due to its high fitting capacity when it comes to real data. In this article, we consider a GTWR model driven by a spatio-temporal noise, colored in space and fractional in time. Concerning the covariates, we consider that they are correlated, taking into account two interaction types between covariates, weak and strong interaction. Under these assumptions, Weighted Least Squares Estimator (WLS) is obtained, as well as its rate of convergence. In order to evidence the good performance of the estimator studied, it is provided a simulation study of four different scenarios, where it is observed that the residuals oscillate with small variation around zero. The STARMA package of the R software allows obtaining a variant of the $R^{2}$ coefficient, with values very close to 1, which means that most of the variability is explained by the model.

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Héctor Araya, Lisandro Fermín, Silfrido Gómez, Tania Roa, Soledad Torres. 2023-09-20. Spatio-Temporal Weighted Regression Model with Fractional-Colored Noise: Parameter estimation and consistency. https://arxiv.org/abs/2309.11402

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