Logical Decisions - Classweb

Using LDW 2: Assessing
Introduction
The second major step of an LDW analysis is to assess
preferences. LDW needs your preferences to define how to
convert the measures to common units and how to compute the
weights of the measures and goals.
The information you enter in the "Structuring the Problem" step is
often relatively objective. Different experts can often agree on the
the structure of the goals hierarchy and the levels for the
alternatives.
The information collected in the preference assessment step is
different. There are generally no objectively right answers to the
preference questions and reasonable people can disagree.
There is no way to avoid the preference assessment step in
decisions with more than one evaluation measure. Some
approaches claim to avoid the step, but usually they just hide it by
combining it with the more objective parts of the analysis. This
makes it very difficult to see what's going on and severely limits
the usefulness of the analysis.
LDW takes a better approach. It clearly separates the objective
parts of the analysis (structuring the problem) from the more
subjective parts (the preference assessments). LDW then provides
tools to identify the effects of different preferences and to identify
those preference judgments that are crucial to the results of the
analysis. This can help focus the discussion about the decision to
those aspects that are most critical.
Preference Sets
Preference sets are where LDW stores the preference judgments
for a single individual or homogeneous group. A preference set
contains all the information LDW needs to compute a ranking of
the alternatives for the "Overall" goal. This information includes
category multipliers, single-measure utility functions, and the
weight assessment information that lets LDW compute the multi-
Section 7 -- Using LDW 2: Assessing 7-1