Logical Decisions - Classweb

the task of evaluating potential reservoir locations and making a
recommendation to the district's board of directors. The team
used an initial screening process to identify a set of potential sites
for evaluation. They used LDW to help develop a quantitative
ranking in support of their more qualitative recommendations.
The team included the ranking results as part of the alternatives
analysis for the project's environmental impact assessment
documents. The reservoir selection example is included in the file
RESEX.LDW.
The reservoir ranking differs from the previous examples in that
the ranking represents the consensus of a team of experts, rather
than the preferences of an individual. The project team used the
LDW preference assessment process as a structured forum where
they could discuss the relative importances of different aspects of
the project. These discussions allowed the project team to arrive
at a consensus preference set and thus a consensus overall
ranking of the alternatives. This ranking also helped the project
team formulate and organize their qualitative recommendations.
The team used sensitivity analyses extensively to identify the
effects of changes in the measures' relative importances.
Six reservoir sites were selected for evaluation. Some alternatives
were enlargements to existing reservoirs, while others were
entirely new sites. Several sites could fit more than one size of
reservoir, but with differing impacts and operational effects. The
team developed multiple alternatives with differing reservoir
sizes at these sites. The sites were ranked independently of size,
with costs being measured on a dollars per acre foot basis. (An
acre foot is a measure of water volume and thus reservoir
capacity.) A separate analysis used the ranking results to select
the recommended reservoir size.
The team developed the goals hierarchy together with the
technical experts and consultants working on the project. To
identify the measures and lower level sub-goals for each major
sub-goal, the team held a meeting with the experts in that area.
These meetings helped ensure that the proper data was collected
for each site and that the data was collected uniformly. Figure 10-
9 shows the goals hierarchy for the reservoir selection process.
Section 10 -- Examples 10-13