  In decision-making methods, it is common to assume that the experts are
honest and professional. However, this is not the case when one or more experts
in the group decision making framework, such as the group analytic hierarchy
process (GAHP), try to manipulate results in their favor. The aim of this paper
is to introduce two heuristics in the GAHP, setting allowing to detect the
manipulators and minimize their effect on the group consensus by diminishing
their weights. The first heuristic is based on the assumption that manipulators
will provide judgments which can be considered outliers with respect to those
of the rest of the experts in the group. The second heuristic assumes that
dishonest judgments are less consistent than the average consistency of the
group. Both approaches are illustrated with numerical examples and simulations.
