The behavior of a generalized random environment integer-valued
autoregressive model of higher order with geometric marginal distribution
and negative binomial thinning operator is dictated by a realization {zn}?,n=1 of an auxiliary Markov chain called random environment process. Element
zn represents a state of the environment in moment n ? N and determines all
parameters of the model in that moment. In order to apply the model, one
first needs to estimate {zn}?,n=1, which was so far done by K-means data
clustering. We argue that this approach ignores some information and
performs poorly in certain situations. We propose a new method for
estimating {zn}?,n=1, which includes the data transformation preceding the
clustering, in order to reduce the information loss. To confirm its
efficiency, we compare this new approach with the usual one when applied on
the simulated and the real-life data, and notice all the benefits obtained
from our method.