library(survey)
source("c:/courses/st446/rcode/confintt.r")

domain <- read.table("c://courses/st446/Rcode/agsrs.txt",header=T)

N=3078        # population size
n=300         # sample size
fpc <- c(rep(N,n))

domaindt <- cbind(domain,fpc)
domaindat <- data.frame(domaindt)
#domaindat

# Create the sampling design
domain_dsgn <- svydesign(data=domaindat, id=~1, fpc=~fpc )
domain_dsgn

# Estimation of the mean for each region (domain)

# Estimation of domain totals

# Domain = NC
esttotal <- svytotal(~ACRES92,subset(domain_dsgn,REGION=="NC"))
esttotal
confint(esttotal,df=n-1)

# Domain = NE
esttotal <- svytotal(~ACRES92,subset(domain_dsgn,REGION=="NE"))
esttotal
confint(esttotal,df=n-1)

# Domain = S
esttotal <- svytotal(~ACRES92,subset(domain_dsgn,REGION=="S"))
esttotal
confint(esttotal,df=n-1)

# Domain = W
esttotal <- svytotal(~ACRES92,subset(domain_dsgn,REGION=="W"))
esttotal
confint(esttotal,df=n-1)

# Estimation of domain means

# Domain = NC
estmean <- svymean(~ACRES92,subset(domain_dsgn,REGION=="NC"))
estmean
confint(estmean,df=n-1)

# Domain = NE
estmean <- svymean(~ACRES92,subset(domain_dsgn,REGION=="NE"))
estmean
confint(estmean,df=n-1)

# Domain = S
estmean <- svymean(~ACRES92,subset(domain_dsgn,REGION=="S"))
estmean
confint(estmean,df=n-1)

# Domain = W
estmean <- svymean(~ACRES92,subset(domain_dsgn,REGION=="W"))
estmean
confint(estmean,df=n-1)