svycontrast {survey} R Documentation

Linear and nonlinearconstrasts of survey statistics

Description

Computes linear or nonlinear contrasts of estimates produced by survey functions (or any object with coef and vcov methods).

Usage

svycontrast(stat, contrasts, ...)

Arguments

 stat object of class svrepstat or svystat contrasts A vector or list of vectors of coefficients, or a call or list of calls ... For future expansion

Details

If contrasts is a list, the element names are used as names for the returned statistics.

If an element of contrasts is shorter than coef(stat) and has names, the names are used to match up the vectors and the remaining elements of contrasts are assumed to be zero. If the names are not legal variable names (eg 0.1) they must be quoted (eg "0.1")

If contrasts is a "call" or list of "call"s, the delta-method is used to compute variances, and the calls must use only functions that deriv knows how to differentiate. If the names are not legal variable names they must be quoted with backticks (eg `0.1`).

Value

Object of class svrepstat or svystat

regTermTest, svyglm

Examples

data(api)
dclus1<-svydesign(id=~dnum, weights=~pw, data=apiclus1, fpc=~fpc)

a <- svytotal(~api00+enroll+api99, dclus1)
svycontrast(a, list(avg=c(0.5,0,0.5), diff=c(1,0,-1)))
## if contrast vectors have names, zeroes may be omitted
svycontrast(a, list(avg=c(api00=0.5,api99=0.5), diff=c(api00=1,api99=-1)))

## nonlinear contrasts
svycontrast(a, quote(api00/api99))
svyratio(~api00, ~api99, dclus1)

[Package survey version 3.18 Index]