poisson_sampling.Rd
Specify a design where units are sampled independently from the population, with known probabilities. This design is often used theoretically, but is rarely used in practice because the sample size is variable. This function calls ppscov
to specify a sparse sampling covariance matrix.
poisson_sampling(p)
Vector of sampling probabilities
Object of class ppsdcheck
data(api)
apipop$prob<-with(apipop, 200*api00/sum(api00))
insample<-rbinom(nrow(apipop),1,apipop$prob)
apipois<-apipop[insample,]
despois<-svydesign(id=~1, prob=~prob, pps=poisson_sampling(apipois$prob), data=apipois)
svytotal(~api00, despois)
#> total SE
#> api00 3952541 280140
## SE formula
sqrt(sum( (apipois$api00*weights(despois))^2*(1-apipois$prob)))
#> [1] 280139.8