Before revision:  As a result, the proposed tail dependence measures overcome the issue that the tail dependence coefficients underestimate the extent of extreme co-movements. We also consider the so-called maximal and minimal tail dependence measures , defined as the maximum and minimum of the tail dependence measures among all tail generating measures for a given copula.
After revision:  Axioms of tail dependence measures , defined as the maximum and minimum of the tail dependence measures among all tail generating measures for a given copula.