Efficient Parameters Estimation Method for the Separable Nonlinear Least Squares Problem
Algorithm 1
Parameter estimation algorithm for the separable nonlinear least squares problem.
Step 1: given initial values , set ,,. is a very small positive number.
Step 2: calculate the matrix of the nonlinear function and Jacobian matrix of the objective function after VP, using (17).
Step 3: calculate the iteration step length and iteration direction using (15) and (16), and then update the nonlinear parameters using (14).
Step 4: if , terminate the algorithm; otherwise, , go to Step 3.
Step 5: calculate linear parameters when is a nonsingular matrix. The least squares method is used to calculate this directly; when is singular or the condition number of exceeds 100, the solution is obtained using (23).