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arXiv · 1506.05830

Asymptotic Theory for M-Estimates in Unstable AR(p) Processes with Infinite Variance Innovations

Maryam Sohrabi·Mahmoud Zarepour
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Abstract

In this paper, we present the asymptotic distribution of M-estimators for parameters in non-stationary AR(p) processes. The innovations are assumed to be in the domain of attraction of a stable law with index $0<\alpha\le2$. In particular, when the model involves repeated unit roots or conjugate complex unit roots, M-estimators have a higher asymptotic rate of convergence compared to the least square estimators and the asymptotic results can be written as It\^{o} stochastic integrals.

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Maryam Sohrabi, Mahmoud Zarepour. 2015-06-18. Asymptotic Theory for M-Estimates in Unstable AR(p) Processes with Infinite Variance Innovations. https://arxiv.org/abs/1506.05830

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