Calculates the analytical gradient of the expected design effect with respect
to the selection probability model coefficients beta.
Arguments
- beta
A numeric vector of coefficients for the selection probability model.
- X
A model matrix for the strata (H rows x K columns).
- pop_pct
A numeric vector of the population proportion in each stratum.
- u_h_omega
A numeric vector of the number of un-responded units in each stratum.
- n_h_omega
A numeric vector of the number of already responded units in each stratum.
- pi_h
A numeric vector of the estimated response propensity in each stratum.
- ...
Additional arguments (not used, for compatibility with optimisers).