| svyratio {survey} | R Documentation |
Ratio estimation and estimates of totals based on ratios for complex
survey samples. Estimating domain (subpopulation) means can be done more easily with svymean.
## S3 method for class 'survey.design2':
svyratio(numerator=formula, denominator,
design,separate=FALSE, na.rm=FALSE,formula, covmat=FALSE,...)
## S3 method for class 'svyrep.design':
svyratio(numerator=formula, denominator, design,
na.rm=FALSE,formula, covmat=FALSE,return.replicates=FALSE, ...)
## S3 method for class 'twophase':
svyratio(numerator=formula, denominator, design,
separate=FALSE, na.rm=FALSE,formula,...)
## S3 method for class 'svyratio':
predict(object, total, se=TRUE,...)
## S3 method for class 'svyratio_separate':
predict(object, total, se=TRUE,...)
## S3 method for class 'svyratio':
SE(object,...,drop=TRUE)
## S3 method for class 'svyratio':
coef(object,...,drop=TRUE)
numerator,formula |
formula, expression, or data frame giving numerator variable(s) |
denominator |
formula, expression, or data frame giving denominator variable(s) |
design |
survey design object |
object |
result of svyratio |
total |
vector of population totals for the denominator variables in
object, or list of vectors of
population stratum totals if separate=TRUE |
se |
Return standard errors? |
separate |
Estimate ratio separately for strata |
na.rm |
Remove missing values? |
covmat |
Compute the full variance-covariance matrix of the ratios |
return.replicates |
Return replicate estimates of ratios |
drop |
Return a vector rather than a matrix |
... |
Other unused arguments for other methods |
The separate ratio estimate of a total is the sum of ratio estimates
in each stratum. If the stratum totals supplied in the total
argument and the strata in the design object both have names these
names will be matched. If they do not have names it is important that
the sample totals are supplied in the correct order, the same order
as shown in the output of summary(design).
When design is a two-phase design, stratification will be on
the second phase.
svyratio returns an object of class svyratio. The
predict method returns a matrix of population totals and
optionally a matrix of standard errors.
Thomas Lumley
Levy and Lemeshow. "Sampling of Populations" (3rd edition). Wiley
svymean for estimating proportions and domain means
calibrate for estimators related to the separate ratio estimator.
data(scd) ## survey design objects scddes<-svydesign(data=scd, prob=~1, id=~ambulance, strata=~ESA, nest=TRUE, fpc=rep(5,6)) scdnofpc<-svydesign(data=scd, prob=~1, id=~ambulance, strata=~ESA, nest=TRUE) # convert to BRR replicate weights scd2brr <- as.svrepdesign(scdnofpc, type="BRR") # use BRR replicate weights from Levy and Lemeshow repweights<-2*cbind(c(1,0,1,0,1,0), c(1,0,0,1,0,1), c(0,1,1,0,0,1), c(0,1,0,1,1,0)) scdrep<-svrepdesign(data=scd, type="BRR", repweights=repweights) # ratio estimates svyratio(~alive, ~arrests, design=scddes) svyratio(~alive, ~arrests, design=scdnofpc) svyratio(~alive, ~arrests, design=scd2brr) svyratio(~alive, ~arrests, design=scdrep) data(api) dstrat<-svydesign(id=~1,strata=~stype, weights=~pw, data=apistrat, fpc=~fpc) ## domain means are ratio estimates, but available directly svyratio(~I(api.stu*(comp.imp=="Yes")), ~as.numeric(comp.imp=="Yes"), dstrat) svymean(~api.stu, subset(dstrat, comp.imp=="Yes")) ## separate and combined ratio estimates of total (sep<-svyratio(~api.stu,~enroll, dstrat,separate=TRUE)) (com<-svyratio(~api.stu, ~enroll, dstrat)) stratum.totals<-list(E=1877350, H=1013824, M=920298) predict(sep, total=stratum.totals) predict(com, total=sum(unlist(stratum.totals))) SE(com) coef(com) coef(com, drop=FALSE) confint(com)