where 𝑰 is the 𝑀 × 𝑀 identity matrix (𝑀 is the number of frequencies), 𝟏 is the 1 × 𝑀 vector whose components are all equal to 1, 𝜎 R and 𝜎 L are the standard deviations of the resistance and inductance, respectively , and 𝜎 𝑛 is the standard deviation of the random error, 𝜺 ∼ 𝒩(0, 𝜎 𝑛 2 𝑰), that is assumed to corrupt the exact impedance, 𝒁 exact , to obtain the experimental impedance, 𝒁 exp . Formally, we set