C ( 3 R , 2 R ) = 1 K + 3 K + 4 K = 1/4 + 1/4 + 1/4 = 0.75 (75 percent)
We therefore have a majority of criteria of 75 percent in favor of 3 R with respect to 2 R . Iterating the same
procedure for other pairs or organizations, we obtain the concordance matrix of Table 4.
Table 4 Concordance Matrix
1 R 2 R
3 R
4 R
1 R
1 1 0.50
2 R
0 0.25 0.25
3 R
0 0.75 0.25
4 R
0.50 0.75 0.75
The concordance indicator in Table 4 varies between 0 and 1. It is equal to 1 only if there is unanimity or a
majority of criteria that are 100 percent in favor of i R with respect to j R . In order to decide on the
superiority of one retail company with respect to another, the decision maker should set a concordance
threshold C*. Generally, it is chosen to be a majority greater than or equal to 75 percent (simple majority
tightened), that is: C* 0.75 (75 percent).
Taking into account the database of Table 4 and the concordance threshold C* we have the following
concordance test:
c T ( i R , j R ) =
1 if C ( i R ; j R ) C*
0 if otherwise
12
The results of concordance test are shown in Table 5.
Table 5 Outcomes of Concordance Test
1 R 2 R
3 R
4 R
1 R
1 1 0
2 R
0 0 0
3 R
0 1 0
4 R
0 1 1
The ELECTRE I methodology considers another step: the construction of discordance test in order to take
into account of an excessive “distance” (dissimilarity) between the scores j ATT ( j R ) and i ATT ( i R ).