I am using lsqnonlin solver for a non-linear data fitting problem.
I get a result which says "Local minima possible. lsqnonlin stopped because the size of the current step is less than the selected value of the step size tolerance".
I have a couple of questions on this regard.
- After displaying the above warning, lsqnonlin gives a solution which is very close to my initial conditions to the parameter values. Why does this happen ?
- What is the difference between local minima possible and local minima found while using these solvers ?
- What should i change in optimoptions to find the local minima using lsqnonlin ?
- How to calculate the standard error of parameter estimates using lsqnonlin ?
I have tried decreasing the function tolerance to 1E-10.
I have also tried decreasing the stepsize tolerance to 1E-10.
Neither of them worked.
What am i missing here ?
I kindly request you to help me in this regard.
Thanks and with best regards,