how to do sensitivity analysis

Hi, I want to do the sensitivity analysis for the PBPK model. I add a program "calculate sensitivities" , but in "SENSIVITITIES TO COMPUTE" ,I can't select my output. My output is the observation in the model, and the observation is the sum of several terms. How can I use the observation as my output to run the sensitivity analysis?

Thank you very much.

Answer 1

[Arthur Goldsipe]

Hi,

It's not currently possible to use an observable as a sensitivity analysis input or output. One workaround is to perform sensitivity analysis on the things the observable depends on. So if your observable is the sum of X and Y, then its sensitivity is the sum of the sensitivities of X and Y.

-Arthur

[Arthur Goldsipe]

Oh, a colleague reminded me that another option is to do global sensitivity analysis (GSA) instead of local sensitivity analysis (LSA). GSA supports sensitivity analysis for observables. If your parameter ranges are narrow, the results may be comparable. And if you are interested in the behavior of your model over a large parameter range, then GSA may actuall be preferable to LSA. You can find more information about GSA here.