Qualitative judgments are subjective judgments based on factors or information that can't be easily or accurately quantified. The importance of objectives, which is by definition subjective, is a qualitative judgment.
The anticipated performance of alternatives with respect to objectives can be based on qualitative judgments and/or quantitative data.
The Analytic Hierarchy Process (AHP) is a structured technique for organizing and analyzing complex decisions, based on mathematics and psychology.2 AHP synthesizes human judgment into accurate ratio scale data. This is significant because it avoids the common, and mathematically meaningless, use of ordinal scale numbers in multiplication.3
With Pairwise Comparisons, participants compare objectives or alternatives with respect to a parent objective. For example, "with respect to body style, which alternative is preferable, and by how much: Subaru Forrester or Ford Escape."
With Rating Scales, participants evaluate alternatives on a predefined scale where the value of the rating scale intensities are on the ratio scale level of measurement, having been derived with pairwise comparisons.
1 https://bizfluent.com/info-11384887-qualitative-judgment-method.html
2 https://en.wikipedia.org/wiki/Analytic_hierarchy_process
3 https://en.wikipedia.org/wiki/Level_of_measurement
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