Skip to contents

Specify Poisson sampling design

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.

Usage

poisson_sampling(p)

Arguments

p

Vector of sampling probabilities

Value

Object of class ppsdcheck

See also

ppscov, svydesign

Examples

data(api)
apipop$prob<-with(apipop, 200*api00/sum(api00))
insample<-as.logical(rbinom(nrow(apipop),1,apipop$prob))
apipois<-apipop[insample,]
despois<-svydesign(id=~1, prob=~prob, pps=poisson_sampling(apipois$prob), data=apipois)

svytotal(~api00, despois)
#>         total     SE
#> api00 4117230 286214

## SE formula
sqrt(sum( (apipois$api00*weights(despois))^2*(1-apipois$prob)))
#> [1] 286214.4