In 1990 Saaty proposed a new solution based on paired
comparisons. Under each criterion we ask which one of two options is better. At
the end we count the relations of the options. The option with the highest sum of “wins”
is the best.
Using the same example as with the other methods, we can come to following tables:
With so few options it is easy to find
the relations and to calculate the “wins”. In fact, Saaty’s method is more sophisticated than just
that, but for us it is enough to use the same weights as before.
We see, that under this method the
advantage of option 3 is more visible. All other options are comparably bad. This is a result that can be seen often:
the method tends to exaggerate relationships because it does not discriminate
between small and large differences.
AHP is widely used in sciences – but only
there. For practice life it covers too many hidden effects.
