Results of three Copula functions with the constant (A3) parameters and the time-varying (A4) parameters for modeling the dependence between two annual maximum streamflow series
Scenario . | Copula . | Parameter ![]() | K–S statistic indicatora . | AIC value . | ||
---|---|---|---|---|---|---|
Variable X1 . | Variable X2 . | Variable X1 . | Variable X2 . | |||
A3 | GH | 2.70 | 0.127 | 0.131 | 43 | 55 |
Frank | 7.85 | 0.144 | 0.157 | 57 | 67 | |
Clayton | 3.46 | 0.172 | 0.175 | 71 | 80 | |
A4 | GH | exp(−414+0.56Ph−0.73RIh) | 0.119 | 0.122 | 33 | 39 |
Frank | exp(−320+0.18Ph−1.45RIh) | 0.149 | 0.154 | 35 | 49 | |
Clayton | exp(−257+0.47Ph−0.69RIh) | 0.173 | 0.171 | 53 | 67 |
Scenario . | Copula . | Parameter ![]() | K–S statistic indicatora . | AIC value . | ||
---|---|---|---|---|---|---|
Variable X1 . | Variable X2 . | Variable X1 . | Variable X2 . | |||
A3 | GH | 2.70 | 0.127 | 0.131 | 43 | 55 |
Frank | 7.85 | 0.144 | 0.157 | 57 | 67 | |
Clayton | 3.46 | 0.172 | 0.175 | 71 | 80 | |
A4 | GH | exp(−414+0.56Ph−0.73RIh) | 0.119 | 0.122 | 33 | 39 |
Frank | exp(−320+0.18Ph−1.45RIh) | 0.149 | 0.154 | 35 | 49 | |
Clayton | exp(−257+0.47Ph−0.69RIh) | 0.173 | 0.171 | 53 | 67 |
aThe K–S test is performed at a significance level of 0.05. The null hypothesis states that the empirical distribution fits the theoretical distribution. If the value of the K–S test indicator is smaller than the value of D(65, 0.05) , the null hypothesis would not be rejected. The variables X1 and X2 are the probability integral transformations for streamflow series Qa and Qh at Ankang and Huangzhuang stations, respectively.