We continued our analysis with the "hook" model. Figure displays the recovered impedances and DRTs. Consistent with the single ZARC, each 2×ZARC, the PWC, and the Gerischer models, the hyper-𝜆 methods captured both the peak and the ring of the "hook" model excellently compared to the corresponding optimal, GCV, and mGCV methods. The "hook" impedance was also closely recovered, see the values of MSE norm,𝑍 exp , MSE norm,𝑍 exact , and MSE 𝛾 norm,exact in Table .