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Value Engineering 169

There may also be situations where the choice of alternatives will require
more complex systems to aid in the evaluation process. Two systems favored
because of their convenience, simplicity, and effectiveness are Pareto voting
and paired comparisons. They may be used separately, or in sequence
depending on the situation. Each of these systems is described in detail in
the following text. They have been found applicable in a large number of
cases and are extremely useful.

There are also cases involving high risk or a substantial amount of money
where even more detailed analysis is required. These may be situations
where risk is critical and alternatives and tradeoffs are necessary. In these
cases, a matrix analysis may be necessary.

Experience has shown that this evaluation process is a difficult task. The
impulse to quickly screen through the list to zero in on the best ideas must
be controlled. The mass of data must be handled systematically to obtain
maximum benefit from the creative phase. Careful screening is essential to
isolating the best concept to carry over into the planning phase where the
idea will be developed into a practical recommendation for action.

7.4.1 Selection and Screening Techniques
A difficult problem that frequently confronts decision makers is the need to
organize a large amount of data, so that one or several of the most important
items may be identified. It may be required to determine which of several
alternatives appears to be the best, or it may be necessary to select a number
of items so that they may be ranked and weighted by order of importance or
some other criteria.

Experience has shown that most people are not able to handle this task
quickly and effectively. For this reason, it was decided to develop a simple
method that would be applicable in most cases. More complex situations
may require more sophisticated methods. However, experience has shown
that a combination of two simple methods, Pareto voting and paired com-
parisons, will satisfy a majority of requirements.

A literature search by the author identified 13 methods for evaluating data
to aid in decision making. The methods are listed in Appendix 2 along with
references, so that further in-depth study by the reader can be made.

Pareto Voting
Pareto voting is based on Pareto’s law of maldistribution. Alfredo Pareto
(1846–1923), a political economist, observed a common tendency of wealth