  In this paper we propose a class of weighted rank correlation coefficients
extending the Spearman's rho. The proposed class constructed by giving suitable
weights to the distance between two sets of ranks to place more emphasis on
items having low rankings than those have high rankings or vice versa. The
asymptotic distribution of the proposed measures and properties of the
parameters estimated by them are studied through the associated copula. A
simulation study is performed to compare the performance of the proposed
statistics for testing independence using asymptotic relative efficiency
calculations.
