I am working on system identification problem, recently I am working on state space estimation.
And in some situation working with ssest (Matlab command), I used an initial system (that I first built form tf command) to start with versus I don't use the initial system to start with but only indicated the order of model. I would get a different result.
This leads to a question I have is whether if state space model suffer from the local minimum issue?
Since I am still pretty new in this field, this could be rather obvious to you.
Any help is appreciated.