Payoff sensitivity

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bartdelft
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Payoff sensitivity

Post by bartdelft »

Hi,

I would like to assess which parameters in my model affect the model KPI's the most. This could be done with the optimization tool using payoff_sensitivity over all constants. However, I am uncertain if this analysis is valid because it calculates the optimization first?
Furthermore, is the sensitivity analysis with ALL_CONSTANTS univariate or multivariate?

Thanks in advance!
Best, Bart
Administrator
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Re: Payoff sensitivity

Post by Administrator »

bartdelft wrote: Wed Jan 12, 2022 12:33 pm I would like to assess which parameters in my model affect the model KPI's the most. This could be done with the optimization tool using payoff_sensitivity over all constants.
Correct, this is the right way to do it.
bartdelft wrote: Wed Jan 12, 2022 12:33 pmHowever, I am uncertain if this analysis is valid because it calculates the optimization first?
Furthermore, is the sensitivity analysis with ALL_CONSTANTS univariate or multivariate?
Univariate. Turn the optimizer off when doing this.
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bartdelft
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Re: Payoff sensitivity

Post by bartdelft »

Thank you.
And is it possible to assess the impact of lookups / Excel imported data-parameters as well?
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Re: Payoff sensitivity

Post by Administrator »

Do you want to know the impact of individual points on a lookup? If yes, you would have to construct the lookup using VECTOR LOOKUP.
https://www.vensim.com/documentation/fn ... ookup.html

If you only want to see the impact of the lookup as a whole, you can add a multiplier to the looked up value, and modify that by +/- 10%. The same would need to be done for data.
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tomfid
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Re: Payoff sensitivity

Post by tomfid »

If you want the multivariate picture, you can use a sensitivity run or MCMC to randomly sample the parameter space, and then export the data and use a visualization tool to explore correlations between inputs and outputs or the payoff.
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