| The estimation of large infrastructural structures, such as bridges among others, has mainly been confined to estimation of their construction value. The estimation procedure of a real, i.e. objective value implies estimation of a larger number of attributes, except the ones that represent construction value of a structure, such as: location, namely location potential, traffic, sociological, ecological and other parameters that represent a set of attributes affecting market value, i.e. usability of infrastructural structures. This paper deals with devising decision -making rules that define this market value, i.e. usability, as well as with reducing attribute core, based on which actual value estimation of bridges is carried out through implementation of rough sets theory. The implementation of this theory facilitates the objective formulation of artificial intelligence rules that define parameters referring to value of bridges determining, as well as to the reduction of decision-making rules that lead to the estimation of their optimal value. |