perfectly. A standard objective function, , is of the form:

where is the Euclidean norm (it will be the $L^2$ norm when the measurements are functions instead of samples) of the residuals. This approach amounts to making use of ordinary least squares, an approach widely used in statistics. However, the Euclidean norm is known to be very sensitive to outliers: to avoid this difficulty we may think of using other distances, for instance the norm, in replacement