# matlab lsqcurvefit parameter estimation journey

The lsqcurvefit solution in matlab converges at different solutions depending upon the initial guess:

Surface represents the error (SSE) between model and data at various combinations of parameters p1 and p2. Red lines represent the path lsqcurvefit takes from initial guess of parameters to the solution marked with red ball.

The 95% confidence in the parameter estimates at the solutions do not overlap...

How does lsqcurvefit estimate error at each iteration of parameter estimation? Why does lsqcurvefit not find the same solution each time? What approaches should be taken to choose a solution?

• The norm of your error looks pretty small in the region you are showing. for a region of $10^6$ by $10^4$ an elevation of $10^{-13}$ it's pretty flat. – nicoguaro Jan 27 '17 at 20:01