IECM 13.0 User Manual > Using the IECM > Setting Parameters > Parameter Screens > Standard Parameters >

Unc

Most parameters support the use of uncertainty. Parameters which support uncertainty will have a button in the Unc column. If the parameter currently has uncertainty, the button will have a question mark in the middle:

The Unc Button with Uncertainty

If the parameter does not currently have uncertainty, the button will be blank:

The Unc Button with No Uncertainty

Click on the button to bring up the Uncertainty Editor.