Abstract
This paper studies the residual-based CUSUM test statistic in first-order Poisson integer-valued autoregressive (PINAR(1)) models. The residuals are calculated with squared difference (SD) estimates, and a retrospective phase (Phase I) analysis is conducted. Moreover, the upper one-sided CUSUM-type chart (RCUSUMV chart) is considered for effectively detecting abnormal shifts in a monitoring phase (Phase II) situation. Numerical experiments show that our method can be good alternative to conventional CUSUM charts when an effective detection and accurate change point estimation for small shifts are primary concerns.
Acknowledgements
We thank the referee for his/her careful reading and valuable comments.