statsmodels.distributions.copula.api.GumbelCopula.tau# GumbelCopula.tau(theta=None)[source]# Kendall’s tau as a function of the copula parameter theta. Joe (2014), p. 172. Parameters: thetafloat, optionalCopula parameter. If not given, then self.theta is used. Returns: floatKendall’s tau corresponding to theta.