“…However, for situations where using an ensemble of 2 p + 1 members is tractable, UKI improves upon EKI by providing uncertainty quantification, instead of collapsing to a point estimate. In particular, when updates and are applied to the augmented data‐model relation , UKI ensures that Σ n in the limit n → ∞ converges toward a Gaussian estimate of parametric uncertainty (Huang, Schneider, & Stuart,
2022),
which involves the augmented forward model
and covariance Γ a defined in Section 3.2. Σ ∞ approximates the covariance of the posterior in Equation around m ∞ if the full loss is evaluated at every UKI iteration and Δ t = 1 (Huang, Huang, et al., 2022).…”