Dealing with Incompleteness of Preferences in Group Decision Making Problems

While considering processes of decision making we often encounter the problem of incomplete information. In group decision making (GDM) problems each decision maker is supposed to provide a matrix that describes his/her preferences over the set of given options. However, we have to take into account that an expert can not be able to define his/her preferences about all the options. Usually the problem is solved by an additional phase of estimating missing values. In the article we want to suggest and discuss a totally different approach that consists in adopting GDM algorithm so as it can deal with incomplete preference matrices