AThe Noisy Quadratic Setting Additional Details

In this section we extend our discussion of the noisy quadratic model (NQM). We first discuss stability in the NQM. We then provide proofs for the results in Section 4. We also extend our discussion of robust stability and the stability of models with hidden states. A.1 Stability In this subsection we expand on the short discussion of key stability results in the body of the paper. We will primarily discuss stability of the nominal system.