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arXiv · 2012.09659

A convolution type model for the intensity of spatial point processes applied to eye-movement data

Francisco Cuevas-Pacheco·Jean-François Coeurjolly·Marie-Hélène Descary
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Abstract

Estimating the first-order intensity function in point pattern analysis is an important problem, and it has been approached so far from different perspectives: parametrically, semiparametrically or nonparametrically. Our approach is close to a semiparametric one. Motivated by eye-movement data, we introduce a convolution type model where the log-intensity is modelled as the convolution of a function $\beta(\cdot)$, to be estimated, and a single spatial covariate (the image an individual is looking at for eye-movement data). Based on a Fourier series expansion, we show that the proposed model \rev{can be viewed as a} log-linear model with an infinite number of coefficients, which correspond to the spectral decomposition of $\beta(\cdot)$. After truncation, we estimate these coefficients through a penalized Poisson likelihood. We illustrate the efficiency of the proposed methodology on simulated data and on eye-movement data.

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Francisco Cuevas-Pacheco, Jean-François Coeurjolly, Marie-Hélène Descary. 2020-12-17. A convolution type model for the intensity of spatial point processes applied to eye-movement data. https://arxiv.org/abs/2012.09659

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