Sens2All technical details

[zhasgul]

I recently tried the Sens2All feature and found it quite intriguing. However, I have a few questions regarding the technical aspects that go beyond what's covered in the documentation.

1) Parameter Value Distribution
One of the primary questions I had was about how parameter values are determined for simulations. Specifically, are these values randomly drawn from a distribution within 10% below and above the parameter values? If so, what is the nature of this distribution—uniform, normal, or something else?

2) Number of Simulation Runs
Another point of curiosity is the number of simulation runs typically conducted. Is there a set value, such as 1000 runs, or is it based on conducting two runs for each parameter—one for 10% up and one for 10% down?

3) Understanding Payoff Percentages
The terms "payoff percentage at final time" and "payoff percentage integrated" were also mentioned in the documentation, but their precise meanings were not fully clear. What exactly do these entail?

4) The Payoff Function
Finally, I wanted to understand the definition of the payoff function used in Sens2All. Is this function based on the sum of squared errors between the initial parameter values and the sensitivity runs or mean absolute percentage error?

I would appreciate any additional information so that I can gain a better understanding of the Sens2All feature and how it functions on a technical level.

[Administrator]

1) Parameter Value Distribution
One of the primary questions I had was about how parameter values are determined for simulations. Specifically, are these values randomly drawn from a distribution within 10% below and above the parameter values? If so, what is the nature of this distribution—uniform, normal, or something else?

No, they are not randomly drawn. Each constant is modified by +/- 10% (or 0.1 if the constant is zero). If you have set bounds for constants, these are respected.
https://vensim.com/documentation/sensitivity2all.html

2) Number of Simulation Runs
Another point of curiosity is the number of simulation runs typically conducted. Is there a set value, such as 1000 runs, or is it based on conducting two runs for each parameter—one for 10% up and one for 10% down?

Two runs for each constant.

3) Understanding Payoff Percentages
The terms "payoff percentage at final time" and "payoff percentage integrated" were also mentioned in the documentation, but their precise meanings were not fully clear. What exactly do these entail?
Finally, I wanted to understand the definition of the payoff function used in Sens2All. Is this function based on the sum of squared errors between the initial parameter values and the sensitivity runs or mean absolute percentage error?

Payoff calculation is in the help system, but it should also be in the Sens2All documentation (we'll fix that).
https://vensim.com/documentation/payoffcomputation.html

There are two payoff calculations in Sens2All, the normal one as detailed in the help, and just the value at final time.