Discussion on "A New Framework for Detection and Identification of Network Parameter Errors"

The authors present an interesting method on Normalized Lagrange Multiplier test for network parameter errors identification. The authors state that validation has so far been solely based on extensive simulations. They also state that the paper presents a new framework by which: (1) the normalized Lagrange multiplier test is re-formulated from the perspective of hypothesis testing, enabling proper handling of missing bad parameter cases; (2) formal proofs are given for the combined utilization of normalized Lagrange multiplier test and normalized residual test for simultaneous handling of measurement and parameter errors; and (3) the concepts of detectability and identifiability for measurement errors are extended to parameter errors, and a systematic approach for identifying critical parameters and critical k-tuples is provided. However, in the paper section II, they present in the problem formulation: \begin{equation*} z=h\left ({x,p_{e}}\right )+e \tag{1}\end{equation*} where $z$ is the measurement vector, $x$ is the state vector, $e$ is the measurement error vector, and $h$ is the nonlinear function linking $x$ and $p_{e}$ to $z$ . Also, \begin{equation*} p_{e}=p-p_{t} \end{equation*} $p_{t}$ being the true parameter value, not known, and $p$ the parameter available from the data.