  This paper derives lower bounds for the mean square errors of parameter
estimators in the case of Poisson distributed data subjected to multiple abrupt
changes. Since both change locations (discrete parameters) and parameters of
the Poisson distribution (continuous parameters) are unknown, it is appropriate
to consider a mixed Cramer-Rao/Weiss-Weinstein bound for which we derive
closed-form expressions and illustrate its tightness by numerical simulations.
