Cross-Entropy (KL) Objective: Expected respondent distribution vs population
Source:R/alsd.R
calculate_entropy.RdMinimizes expected KL divergence between expected respondent shares and population shares. Expected respondent counts per stratum are S_h = n_h_omega + u_h_omegapi_hsigmoid(X beta). The additional respondents from the next wave are A_h * Sigma; their expected shares are q_h = (A_hSigma)/sum(A_hSigma). We compare q_h against pop_pct via KL(pop || q) or KL(q || pop). Here we use KL(pop || q) for stability where pop_pct>0.
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).