The functional AR(1) process with a unit root

Nelson Muriel

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arXiv · 1512.01844

The functional AR(1) process with a unit root

Nelson Muriel

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Abstract

We define strong and weak unit roots for the functional AR(1) process and give some theoretical examples. It is shown that a functional form of cointegration occurs in which only a finite number of common trends exist. Using functional Principal Component Analysis we illustrate the presence of functional unit roots in two demographic data sets. We close with some remarks concerning our assumptions and the possibility of generalizing our results.

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Nelson Muriel. 2015-12-06. The functional AR(1) process with a unit root. https://arxiv.org/abs/1512.01844

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