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Hi all,

When I first changed the amount of a flow, the gmean in the lognormal uncertainty analysis changed automatically. However, I changed the amount of the flows again and the gmean hasn't changed. I have calculated the gsigma myself instead of using the "data quality entry" option. Is there a way to make the gmean automatically change when modifying the amount of the flows?

Thanks
in openLCA by (200 points)

1 Answer

+1 vote
by (7.2k points)
When I understood you correctly, you maybe meant that if the lognormal uncertainty of an exchange is selected for the first time, the pre-filled value for gmean is the amount of the exchange itself.

When you give your exchanges an uncertainty value and there was no uncertainty entry before, the software will put inside the gmean field for log-normal distributions the amount of the exchange as a default. And you are right, that usually the gmean value is equal to the exchange amount.

But if these two values would be fixed and coupled, there would be less flexibility for users to set exchange amounts and mean values independently, since this condition is not true for all uncertainty distributions.

When you set-up a process and you change the amounts, it does not take much time to also change the gmean, no? Or are you looking for a parameterization of the uncertainty values?

Best wishes,

Conrad
by (200 points)
Thanks for the answer Conrad. It is fine once I know this, I changed them manually now. I didn't realize at first, that's why I had a lot of values to change, but it is done now. For the future, I know I should also change the gmean if I change the amount.

Best,

Arrate
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