svyby {survey} | R Documentation |
Compute survey statistics on subsets of a survey defined by factors.
svyby(formula, by ,design,...) ## Default S3 method: svyby(formula, by, design, FUN, ..., deff=FALSE,keep.var = TRUE, keep.names = TRUE,verbose=FALSE, vartype=c("se","ci","ci","cv","cvpct","var"), drop.empty.groups=TRUE, covmat=FALSE, return.replicates=FALSE) ## S3 method for class 'svyby': SE(object,...) ## S3 method for class 'svyby': deff(object,...) ## S3 method for class 'svyby': coef(object,...)
formula |
A formula specifying the variables to pass to
FUN (or a matrix, data frame, or vector) |
by |
A formula specifying factors that define subsets, or a list of factors. |
design |
A svydesign or svrepdesign object |
FUN |
A function taking a formula and survey design object as its first two arguments. |
... |
Other arguments to FUN |
deff |
Request a design effect from FUN |
keep.var |
If FUN returns a svystat object, extract
standard errors from it |
keep.names |
Define row names based on the subsets |
verbose |
If TRUE , print a label for each subset as it is
processed. |
vartype |
Report variability as one or more of standard error, confidence interval, coefficient of variation, percent coefficient of variation, or variance |
drop.empty.groups |
If FALSE , report NA for empty
groups, if TRUE drop them from the output |
covmat |
If TRUE , compute covariances between estimates for
different subsets (currently only for replicate-weight
designs). Allows svycontrast to be used on output. |
return.replicates |
Only for replicate-weight designs. If
TRUE , return all the replicates as an attribute of the result |
object |
An object of class "svyby" |
The variance type "ci" asks for confidence intervals, which are produced
by confint
. In some cases additional options to FUN
will
be needed to produce confidence intervals, for example,
svyquantile
needs ci=TRUE
An object of class "svyby"
: a data frame showing the factors and the results of FUN
Asking for a design effect (deff=TRUE
) from a function
that does not produce one will cause an error or incorrect formatting
of the output. The same will occur with keep.var=TRUE
if the
function does not compute a standard error.
svytable
and ftable.svystat
for
contingency tables, ftable.svyby
for pretty-printing of svyby
data(api) dclus1<-svydesign(id=~dnum, weights=~pw, data=apiclus1, fpc=~fpc) svyby(~api99, ~stype, dclus1, svymean) svyby(~api99, ~stype, dclus1, svyquantile, quantiles=0.5,ci=TRUE,vartype="ci") ## without ci=TRUE svyquantile does not compute standard errors svyby(~api99, ~stype, dclus1, svyquantile, quantiles=0.5, keep.var=FALSE) svyby(~api99, list(school.type=apiclus1$stype), dclus1, svymean) svyby(~api99+api00, ~stype, dclus1, svymean, deff=TRUE,vartype="ci") svyby(~api99+api00, ~stype+sch.wide, dclus1, svymean, keep.var=FALSE) rclus1<-as.svrepdesign(dclus1) svyby(~api99, ~stype, rclus1, svymean) svyby(~api99, ~stype, rclus1, svyquantile, quantiles=0.5) svyby(~api99, list(school.type=apiclus1$stype), rclus1, svymean, vartype="cv") svyby(~enroll,~stype, rclus1,svytotal, deff=TRUE) svyby(~api99+api00, ~stype+sch.wide, rclus1, svymean, keep.var=FALSE) ## comparing subgroups using covmat=TRUE mns<-svyby(~api99, ~stype, rclus1, svymean,covmat=TRUE) vcov(mns) svycontrast(mns, c(E = 1, M = -1)) str(svyby(~api99, ~stype, rclus1, svymean,return.replicates=TRUE)) ## extractor functions (a<-svyby(~enroll, ~stype, rclus1, svytotal, deff=TRUE, verbose=TRUE, vartype=c("se","cv","cvpct","var"))) deff(a) SE(a) cv(a) coef(a) ## ratio estimates svyby(~api.stu, by=~stype, denominator=~enroll, design=dclus1, svyratio) ## empty groups svyby(~api00,~comp.imp+sch.wide,design=dclus1,svymean) svyby(~api00,~comp.imp+sch.wide,design=dclus1,svymean,drop.empty.groups=FALSE)