Mestim
This package provides a flexible framework for estimating the variance-covariance matrix of estimated parameters. Estimation relies on providing unbiased estimating functions to compute the empirical sandwich variance. what is this? :monkey:
Installation
For latest release
devtools::install_github("fcgrolleau/Mestim")For stable release
install.packages("Mestim")Implementation
library(Mestim)
# Put estimated parameters in a list
thetas_hat <- list(theta_1=coef(mod)[1], theta_2=coef(mod)[2])
# Build a list of unbiased estimating functions
# NB: parameters' names must be consistent with the previous list
M_1 <- expression( ((1/(1+exp( -( theta_1 * x_1 + theta_2 * x_2 ) ))) - y ) * x_1 )
M_2 <- expression( ((1/(1+exp( -( theta_1 * x_1 + theta_2 * x_2 ) ))) - y ) * x_2 )
est_functions <- list(M_1, M_2)
## Pass arguments to get_vcov and obtain what you are looking for
res <- get_vcov(data=dat, thetas=thetas_hat, M=est_functions)Find more information in the introduction vignette.
Authors
This package is written and maintained by François Grolleau (francois.grolleau@aphp.fr).
References
- Boos DD. and Stefanski, LA.
Essential Statistical Inference. 2013. [Springer]
- Tsiatis, AA., Davidian, M., Holloway, ST. and Laber, EB.
Dynamic Treatment Regimes: Statistical Methods for Precision Medicine. 2019. [CRC Press]