Logical Decisions - Classweb

Changing Weight Assessment Methods
LDW makes it easy to change the weight assessment method for a
goal. Just select a new method from the list in the weight
assessment dialog box. LDW will warn you that you might lose
some preference information if you have already done
assessments with the old method. When you change between
methods, LDW tries to assign parameters in the new method that
result in the same weights as in the old method. Thus, if you
change from the "Smarter" to the "Smart" method, LDW computes
and saves a set of swing weights that result in the same weights as
the smarter importance ordering. If you then change to the
tradeoff method, LDW computes and saves a set of tradeoffs
(against the most important member) that result in the same
weights as the swing weights. This lets you get an initial
assessment using an "easy" method and still check your results
using a more "difficult" method.
The Relationship Between Measure Ranges and Weights
One of the most misunderstood concepts in multi-objective
decision analysis is the relationship between measure ranges and
weights.
The common misconception is that there is no relationship and
that measure weights can be assessed based on the names of the
measures alone. This is incorrect. There is a strong relationship
between measure ranges and weights.
! As the range for a measure gets wider, its
weight should increase.
Weights in LDW are computed based on the most and least
preferred levels for each measure established in the measure’s
properties dialog box. This range is also used in the conversion to
common units step.
Establishing a measure’s range. There are several approaches
to establishing a measure’s range.
One approach is the use the exact range of the alternatives. This
may cause problems due to the more or less random numbers that
will define the range. Also the range may have to be changed
frequently as alternatives are added and deleted.
9-50 Section 9 -- In Depth