The calculation is in the weighing of priorities so they're clearly ranked in a hierarchy. Hence the third sentence of the wiki article on the subject:
"The theory postulates that an individual will perform a cost-benefit analysis to determine whether an option is right for them."
An analysis is calculative in laying out the explicit relations between the parts. Heuristic, intuitive thinking doesn't work that way. It relies on shortcuts that are often effective but that also make us prone to biases that can be exploited.