
Semiparametric Bernstein-von Mises for a smooth functional
Source:R/gh_c12_4.R
Ghosalsemiparabvm.Rdsqrt(n)(psi(G_post) - psi(F0)) tends to N(0, sigma_eff^2) for a smooth functional psi. The variance in the limit is the SEMIPARAMETRIC EFFICIENCY BOUND, not merely some variance: the Bayes procedure is asymptotically efficient without being told the functional in advance. Here psi is the mean and the truth uniform, so the bound is var(X) = 1/12.
Details
Formula: psi(G_post) = (alpha/2 + sum_i X_i) / (alpha + n); Var(sqrt(n)(psi(G_post) - 1/2)) -> 1/12.
References
Ghosal & van der Vaart (2017), Fundamentals of Nonparametric Bayesian Inference, CUP, section 12.3.
Examples
# \donttest{
set.seed(1)
r <- Ghosalsemiparabvm(); TRUE
#> [1] TRUE
# }