  A recent work of the authors on the analysis of pairwise comparison matrices
that can be made consistent by the modification of a few elements is continued
and extended. Inconsistency indices are defined for indicating the overall
quality of a pairwise comparison matrix. It is expected that serious
contradictions in the matrix imply high inconsistency and vice versa. However,
in the 35-year history of the applications of pairwise comparison matrices,
only one of the indices, namely CR proposed by Saaty, has been associated to a
general level of acceptance, by the well known ten percent rule. In the paper,
we consider a wide class of inconsistency indices, including CR, CM proposed by
Koczkodaj and Duszak and CI by Pel\'aez and Lamata. Assume that a threshold of
acceptable inconsistency is given (for CR it can be 0.1). The aim is to find
the minimal number of matrix elements, the appropriate modification of which
makes the matrix acceptable. On the other hand, given the maximal number of
modifiable matrix elements, the aim is to find the minimal level of
inconsistency that can be achieved. In both cases the solution is derived from
a nonlinear mixed-integer optimization problem. Results are applicable in
decision support systems that allow real time interaction with the decision
maker in order to review pairwise comparison matrices.
