Page 5 - Grazia_Napoli_2014

The judgments, expressed in the Saaty's fundamental scale (ratio scale of 1-9), are
filled in the paired comparison matrix that gives a supermatrix (unweighed
supermatrix) that is multiplied by the vector of the weights of the clusters (weighed
supermatrix) and then it is raised to a limiting power to obtain the “limit
1
supermatrix”. A column of this last matrix represents the final priority vector .

low complexity medium

high complexity

Figure 3. Complexity of the vertical connection elements

The data are processed by adopting two systems of weights (Tab. 1). The system of
weights A is corresponding to the social use values which give great importance to
the “Architectural Characteristics” and “Environmental characteristics” clusters for
which it is assumed that this type of elements are not just useful, but essential for a
real social welfare, and that a mere economic utilitarianism must be overcome.
While the system of weights B gives the most importance to the “Technical
characteristics” and “Economic-financial characteristics” clusters. The resulting
local and global priorities are illustrated in Table 2. According to the ranking A,
A.U.22 is the best alternative, while according to the ranking B, A.U.11 becomes
the best project. The results in Tables 2 show the positions of the alternatives are
affected by the variation of the system of weights. However they are quite stable,
namely for A.U.23, A.U.26 and A.U.2 (among the worst), beside A.U.11 and
A.U.22 (among the best) have inverted their positions (because of the little gap
between the two projects’ values).

1 The data were processed using the software available in the website
www.superdecision.com.

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