Identifiability can be defined as the existence of a unique maximum likelihood estimator for any arbitrary data set. When models become unidentifiable, issues occur as the fitted model can diverge significantly from the true data generating process, rendering inference and prediction essentially useless. Understanding when Hawkes processes become unidentifiable has yet to be fully explored; however, in much of the current literature identifiability is either assumed or ignored entirely. This paper discusses under what circumstances Hawkes processes become unidentifiable: providing a theoretical interpretation of how the structure of Hawkes processes affect the identifiability of the process itself.
This paper is due to be added after the reviewing process has been completed and a pdf will be provided here. For the more interested reader, please feel free to contact me directly and I am happy to discuss this research.