Since EnKF and VEnKF are stochastic methods, we display rms errors averaged over 10 repetitions.
For instance, VEnKF with N = 10 performs equally well as EnKF with N = 20.
4, we compare KF, VEnKF, and EnKF using ensemble sizes N = (5,10, 20, 50,100) for VEnKF and EnKF.
Next, we compared VEnKF to EnKF in a case, where the dimension is much higher (j' = 7, d = [S.
The standard EnKF is criticized in many papers because of the additional sampling errors brought in by randomly perturbing the observations.
Hybrid EnKF methods that incorporate features from both EnKF and variational methods (as VEnKF) have been found appealing in many studies.