Extract variance/covariance matrix from parameters of svymean

Extract variance/covariance matrix from parameters of svymean

nhanes_vcov(nhanes_data, columns, weights_column = "", filter = "")

Arguments

nhanes_data

data frame containing NHANES data
columns

columns to include in svymean for
weights_column

name of the weights column
filter

logical expression used to subset the data

Value

a data frame

Examples



# NOT RUN {
dat <- nhanes_load_data("PFC_G", "2011-2012", demographics = TRUE)

nhanes_vcov(dat, c("LBXPFOA", "LBXPFOS"))
# }