Optimization

[addor]

I used Optimization for several times, and always it worked. Now I get the message:

No optimization, not creating optimize output file
The final payoff is -0.0318305

What I'm doing wrong?

Regards,
Peter

[Administrator]

Can you upload the model causing the problem?

[bob@vensim.com]

In the optimization control dialog there is a dropdown to select the optimizer - the choices are Powell and Off. You have selected Off and not set up multiple restarts or sensitivity so there is nothing to do.

[addor]

Oh yes, this morning I played around with the optimizer and multiple restart parameters as I have noted that in earlier trials they were set otherwise.
Now as I have chosen Powell and multiple restarts on it is working. Thank you.

Is it possible that with 5.7 the default parameters have slightly changed?

The model isn't exciting. And to be honest: I found the best parameters a and b manually. Optimization only confirms my findings. This is also a worth information.

Peter

[bob@vensim.com]

The optimizer was substantially improved with version 5.7. There were no changes to default parameters but the interpretation of the convergence bounds was redone to make improve the control of convergence during optimization.