4 Uncertainty Considerations
Variability and parameter uncertainty of unit process' inputs
and outputs, e.g. measurement uncertainties, process
specific variations, temporal variations, etc., are expressed
in quantitative terms on the level of individual inputs and
outputs of unit processes. This type of uncertainty has been
treated consistently and in a quantified way within the
ecoinvent project. Lognormal distribution has been assumed
for all unit processes of ecoinvent data v1.1.2