This function creates an object to store the number of clusters sampled
within each stratum (at each stage of multistage sampling) and the
number of clusters available in the population. It is called by
svydesign, not directly by the user.
as.fpc(df, strata, ids,pps=FALSE)A data frame or matrix with population size information
A data frame giving strata at each stage
A data frame giving cluster ids at each stage
if TRUE, fpc information may vary within a stratum
and must be specified as a proportion rather than a population sizes
An object of class survey_fpc
The population size information may be specified as the number of clusters in the population or as the proportion of clusters sampled.