Nonparametric measures of angular-angular association
两个角度变量关联的非参数度量
A general model is proposed for association between two angular variables, corresponding to monotone association between two linear variables. A U-statistic analogous to Kendall's tau is developed to estimate the degree of this association and its distributional properties studied. A simple modification of Mardia's rank angular-angular correlation coefficient is proposed as the appropriate analogue of Spearman's rho for assessing this association.